SC TO-T

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE TO

Tender Offer Statement Under Section 14(d)(1) or 13(e)(1)
of the Securities Exchange Act of 1934

ELKCORP
(Name of Subject Company (Issuer))

BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.
(Names of Filing Persons—Offerors)

COMMON STOCK, PAR VALUE $1.00 PER SHARE
(Title of Class of Securities)

287456107
(CUSIP Number of Class of Securities)

BMCA Acquisition Sub Inc.
1361 Alps Road
Wayne, NJ 07470
(201) 628-3000
Attention: John F. Rebele
(Name, Address and Telephone Numbers of Person
Authorized to Receive Notices and Communications on Behalf of Filing Persons)

Copies to:

Maurice M. Lefkort, Esq.
Willkie Farr & Gallagher LLP
787 Seventh Avenue
New York, NY 10019-6099
(212) 728-8000

CALCULATION OF FILING FEE

Transaction Valuation*	Amount of Filing Fee*
$946,939,014	$101,322.48

*

The amount of the filing fee, in accordance with Rule 0-11 of the Securities Exchange Act of 1934, is calculated by multiplying the transaction valuation by 0.000107. For purposes of calculating the filing fee only, the transaction valuation was determined by multiplying the purchase price of $42.00 per share by the sum of (i) the 20,624,468 shares of common stock, par value $1.00 per share, of ElkCorp (the "Shares"), issued and outstanding as of January 5, 2007, according to the Schedule 14D-9 filed by ElkCorp with the Securities and Exchange Commission (the "Commission") on January 8, 2007 (as amended, the "Schedule 14D-9"); (ii) the stock options granted to purchase 1,339,999 Shares issued and outstanding as of January 5, 2007, according to the Schedule 14D-9; and (iii) the 581,700 Shares subject to outstanding performance share awards as of January 5, 2007, according to the Schedule 14D-9.

ý

Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) of the Exchange Act and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid:	$96,793.22**	Filing Party:	Building Materials
Form or Registration No.:	005-02742		Corporation of America
		Date Filed:	December 20, 2006, January 3, 2007, January 8, 2007, January 9, 2007 and January 18, 2007

**

Building Materials Corporation of America previously paid $96,793.22 pursuant to its Schedule TO, filed with the Commission on December 20, 2006, as amended and supplemented by Amendment No. 1 thereto filed with the Commission on January 3, 2007, by Amendment No. 2 thereto filed with the Commission on January 8, 2007 and by Amendment No. 3 filed thereto with the Commission on January 9, 2007 (as amended, the "BMCA Schedule TO"). BMCA Acquisition Sub Inc. has paid $4,529.26, the difference between the total amount of the filing fee and the amount previously paid by Building Materials Corporation of America pursuant to the BMCA Schedule TO.

o

Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer:

o

Check the appropriate boxes below to designate any transactions to which the statement relates.

ý

third-party tender offer subject to Rule 14d-1.

o

issuer tender offer subject to Rule 13e-4.

o

going-private transaction subject to Rule 13e-3.

ý

amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: o

(Continued on following pages)

SCHEDULE TO

        This Tender Offer Statement on Schedule TO (the "Schedule TO") relates to the offer by BMCA Acquisition Sub Inc. (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), pursuant to Rule 14d-1 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), in connection with Purchaser's offer to purchase all of the issued and outstanding shares of common stock, par value $1.00 per share (the "Common Stock"), of ElkCorp, a Delaware corporation (the "Company"), and the associated Series A Participating Preferred Stock purchase rights (the "Rights" and, together with the Common Stock, the "Shares") at a price of $42.00 per Share, net to the seller in cash (less applicable withholding taxes and without interest). The terms and conditions of the offer are described in the Offer to Purchase, dated January 18, 2007 (the "Offer to Purchase") and the related Letter of Transmittal (which, together with any supplements or amendments, collectively constitute the "Offer"), copies of which are attached as Exhibit (a)(1)(A) and (a)(1)(B) hereto, respectively. The information set forth in the Offer to Purchaser and the related Letter of Transmittal is incorporated herein by reference with respect to the Introduction, Items 1-9 and Item 11 of this Schedule TO.

ITEM 10.	FINANCIAL STATEMENTS.
	Not applicable.
ITEM 12.	MATERIALS TO BE FILED AS EXHIBITS.
(a) (1) (A)	Offer to Purchase, dated January 18, 2007.
(a) (1) (B)	Letter of Transmittal.
(a) (1) (C)	Notice of Guaranteed Delivery.
(a) (1) (D)	Letter to Brokers, Dealers, Commercial Banks, Trust Companies and other Nominees.
(a) (1) (E)	Form of Letter to Clients for Use by Brokers, Dealers, Commercial Banks, Trust Companies and Nominees.
(a) (1) (F)	Form of Letter to Participants in the ElkCorp Employee Stock Ownership Plan.
(a) (1) (G)	Trustee Direction Form.
(a) (1) (H)	Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9.
(a) (1) (I)	Press Release, dated January 18, 2007, Announcing the Commencement of the Offer.
(a) (1) (J)	Summary Advertisement, dated January 18, 2007, Appearing in the New York Times.
(a) (1) (K)	Letter from Samuel J. Heyman, general partner of Heyman Investment Associates Limited Partnership, to Mr. Robert B. Tafaro, Chief Executive Officer and President of Building Materials Corporation of America, dated August 28, 2006.
(a) (1) (L)	Press Release, dated December 17, 2006.
(a) (1) (M)	Letter, dated December 17, 2006, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to Thomas D. Karol, Chairman of the Board and Chief Executive Officer of ElkCorp.

1

(a) (1) (N)	Press Release, dated December 18, 2006.
(a) (1) (O)	Letter, dated December 18, 2006, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Board of Directors of ElkCorp.
(a) (1) (P)	Press Release, dated December 20, 2006.
(a) (1) (Q)	Letter, dated January 5, 2007, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Special Committee of the Board of Directors of ElkCorp.
(a) (1) (R)	Letter, dated January 9, 2007, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Special Committee of the Board of Directors of ElkCorp.
(a) (1) (S)	Letter, dated January 18, 2007, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Special Committee of the Board of Directors of ElkCorp.
(b) (1)	Senior Secured Financing Commitment Letter, between Bear, Stearns & Co. Inc., Bear Stearns Corporate Lending Inc., Deutsche Bank AG New York Branch, Deutsche Bank Securities Inc., JPMorgan Chase Bank, N.A., J.P. Morgan Securities, Inc., BMCA Acquisition Sub Inc., BMCA Acquisition Inc. and Building Materials Corporation of America, dated January 17, 2007.
(b) (2)	Bridge Commitment Letter, between Bear Stearns Corporate Lending Inc., Deutsche Bank AG Cayman Islands Branch JPMorgan Chase Bank, N.A., BMCA Acquisition Sub Inc., BMCA Acquisition Inc. and Building Materials Corporation of America, dated January 17, 2007.
(d) (1)	Confidentiality Agreement, dated as of December 29, 2006, by and among the Company, Heyman Investment Associates Limited Partnership and Purchaser.

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SIGNATURE

        After due inquiry and to the best of their knowledge and belief, the undersigned hereby certify as of January 18, 2007 that the information set forth in this statement is true, complete and correct.

BMCA Acquisition Sub Inc.
By:	/s/  ROBERT B. TAFARO
	Name:  Robert B. Tafaro Title:    President and Chief Executive Officer
BMCA Acquisition Inc.
By:	/s/  ROBERT B. TAFARO
	Name:  Robert B. Tafaro Title:    President and Chief Executive Officer

EXHIBIT INDEX

EXHIBIT NO.	DESCRIPTION
(a) (1) (A)	Offer to Purchase, dated January 18, 2007.
(a) (1) (B)	Letter of Transmittal.
(a) (1) (C)	Notice of Guaranteed Delivery.
(a) (1) (D)	Letter to Brokers, Dealers, Commercial Banks, Trust Companies and other Nominees.
(a) (1) (E)	Form of Letter to Clients for Use by Brokers, Dealers, Commercial Banks, Trust Companies and Nominees.
(a) (1) (F)	Form of Letter to Participants in the ElkCorp Employee Stock Ownership Plan.
(a) (1) (G)	Trustee Direction Form.
(a) (1) (H)	Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9.
(a) (1) (I)	Press Release, dated January 18, 2007, Announcing the Commencement of the Offer.
(a) (1) (J)	Summary Advertisement, dated January 18, 2007, Appearing in the New York Times.
(a) (1) (K)	Letter from Samuel J. Heyman, general partner of Heyman Investment Associates Limited Partnership, to Mr. Robert B. Tafaro, Chief Executive Officer and President of Building Materials Corporation of America, dated August 28, 2006.
(a) (1) (L)	Press Release, dated December 17, 2006.
(a) (1) (M)	Letter, dated December 17, 2006, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to Thomas D. Karol, Chairman of the Board and Chief Executive Officer of ElkCorp.
(a) (1) (N)	Press Release, dated December 18, 2006.
(a) (1) (O)	Letter, dated December 18, 2006, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Board of Directors of ElkCorp.
(a) (1) (P)	Press Release, dated December 20, 2006.
(a) (1) (Q)	Letter, dated January 5, 2007, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Special Committee of the Board of Directors of ElkCorp.
(a) (1) (R)	Letter, dated January 9, 2007, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Special Committee of the Board of Directors of ElkCorp.
(a) (1) (S)	Letter, dated January 18, 2007, from Robert B. Tafaro, President and Chief Executive Officer of Building Materials Corporation of America, to the Special Committee of the Board of Directors of ElkCorp.
(b) (1)	Senior Secured Financing Commitment Letter, between Bear, Stearns & Co. Inc., Bear Stearns Corporate Lending Inc., Deutsche Bank AG New York Branch, Deutsche Bank Securities Inc., JPMorgan Chase Bank, N.A., J.P. Morgan Securities, Inc., BMCA Acquisition Sub Inc., BMCA Acquisition Inc. and Building Materials Corporation of America, dated January 17, 2007.

(b) (2)	Bridge Commitment Letter, between Bear Stearns Corporate Lending Inc., Deutsche Bank AG Cayman Islands Branch JPMorgan Chase Bank, N.A., BMCA Acquisition Sub Inc., BMCA Acquisition Inc. and Building Materials Corporation of America, dated January 17, 2007.
(d) (1)	Confidentiality Agreement, dated as of December 29, 2006, by and among the Company, Heyman Investment Associates Limited Partnership and Purchaser.

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SCHEDULE TO
SIGNATURE
EXHIBIT INDEX

EX-99.(A)(1(A)

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Exhibit (a)(1)(A)

Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(including the Associated Series A Participating Preferred Stock Purchase Rights)
of
ELKCORP
at
$42.00 NET PER SHARE
by
BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, FEBRUARY 14, 2007, UNLESS THE OFFER IS EXTENDED.

THE OFFER IS CONDITIONED UPON, AMONG OTHER THINGS, (1) THERE BEING VALIDLY TENDERED AND NOT WITHDRAWN PRIOR TO THE EXPIRATION OF THE OFFER SUCH NUMBER OF SHARES OF COMMON STOCK (THE "SHARES") OF ELKCORP (THE "COMPANY") THAT, WHEN ADDED TO THE SHARES ALREADY BENEFICIALLY OWNED BY BUILDING MATERIALS CORPORATION OF AMERICA ("BMCA"), AN INDIRECT PARENT OF BMCA ACQUISITION SUB INC. (INCLUDING ANY SUCCESSOR THERETO, THE "PURCHASER") SHALL CONSTITUTE A MAJORITY OF THE SHARES OUTSTANDING, ON A FULLY DILUTED BASIS, (2) THE BOARD OF DIRECTORS OF THE COMPANY (THE "COMPANY BOARD") ADOPTING A RESOLUTION PROVIDING THAT THE COMPANY WILL NOT BE SUBJECT TO SECTION 203 OF THE DELAWARE GENERAL CORPORATION LAW OR THAT THE OFFER AND THE PROPOSED SECOND STEP MERGER DESCRIBED HEREIN (THE "PROPOSED MERGER") ARE EXEMPT THEREFROM OR THE PURCHASER BEING SATISFIED, IN ITS REASONABLE DISCRETION, THAT, AFTER THE CONSUMMATION OF THE OFFER, SECTION 203 WILL BE INAPPLICABLE TO THE OFFER AND THE PROPOSED MERGER, (3) THE COMPANY BOARD AMENDING THE COMPANY'S SHAREHOLDER RIGHTS PLAN TO RENDER THE PREFERRED STOCK PURCHASE RIGHTS ISSUED THEREUNDER INAPPLICABLE TO THE OFFER AND PROPOSED MERGER OR BY ACTING TO REDEEM THE SERIES A PARTICIPATING PREFERRED STOCK PURCHASE RIGHTS, OR THE PURCHASER BEING SATISFIED, IN ITS REASONABLE DISCRETION, THAT THE PREFERRED STOCK PURCHASE RIGHTS ARE INVALID OR OTHERWISE INAPPLICABLE TO THE OFFER AND THE PROPOSED MERGER, AND (4) THE COMPANY BOARD ADOPTING A RESOLUTION APPROVED BY MORE THAN ²/3 OF THE DIRECTORS OF THE COMPANY APPROVING THE ACQUISITION OF ADDITIONAL SHARES BY THE PURCHASER PURSUANT TO THE OFFER AND THE PROPOSED MERGER FOR THE PURPOSES OF ARTICLE THIRTEENTH OF THE COMPANY'S RESTATED CERTIFICATE OF INCORPORATION, OR THE PURCHASER BEING SATISFIED, IN ITS REASONABLE DISCRETION, THAT THE PROVISIONS OF ARTICLE THIRTEENTH ARE OTHERWISE INAPPLICABLE TO THE OFFER AND THE PROPOSED MERGER. THESE CONDITIONS, LIKE ALL OTHERS, MUST BE SATISFIED OR WAIVED PRIOR TO THE EXPIRATION OF THE OFFER. SEE SECTIONS 1 AND 14 FOR MORE INFORMATION.

(Cover continued on next page)

The Dealer Manager for the Offer is:
Bear, Stearns & Co. Inc.

January 18, 2007

(Cover continued from previous page)

BMCA ACQUISITION INC. AND THE PURCHASER INTEND TO CONTINUE TO SEEK TO NEGOTIATE WITH THE COMPANY WITH RESPECT TO A BUSINESS COMBINATION WITH THE COMPANY. SATISFACTION OF THE PRINCIPAL CONDITIONS TO THE OFFER, WITH THE EXCEPTION OF THE MINIMUM TENDER CONDITION, IS WITHIN THE CONTROL OF THE COMPANY'S BOARD. UNLESS THE COMPANY'S BOARD ACTS TO REMOVE THESE IMPEDIMENTS TO THE CONSUMMATION OF THE OFFER, THE OFFER WILL NOT BE ABLE TO PROCEED.

THE PURCHASER RESERVES THE RIGHT TO AMEND THE OFFER (INCLUDING AMENDING THE NUMBER OF SHARES AND ASSOCIATED SERIES A PARTICIPATING PREFERRED STOCK PURCHASE RIGHTS TO BE PURCHASED AND THE OFFER PRICE (AS DEFINED HEREIN)) UPON ENTERING INTO A MERGER AGREEMENT WITH THE COMPANY, OR TO NEGOTIATE A MERGER AGREEMENT WITH THE COMPANY NOT INVOLVING A TENDER OFFER. SUCH A MERGER AGREEMENT COULD INVOLVE, AMONG OTHER POSSIBILITIES, THE PURCHASER TERMINATING THE OFFER AND THE CONVERSION OF THE SHARES, UPON CONSUMMATION OF SUCH MERGER, INTO CASH IN SUCH AMOUNTS AS ARE NEGOTIATED BY THE PURCHASER AND THE COMPANY.

IMPORTANT

        If you wish to tender all or any of your Shares prior to the expiration of the Offer, you should either (1) complete and sign the Letter of Transmittal (or a facsimile thereof) in accordance with the instructions in the Letter of Transmittal included with this Offer to Purchase, have your signature thereon guaranteed if required by Instruction 1 to the Letter of Transmittal, mail or deliver the Letter of Transmittal (or such facsimile thereof) and any other required documents to the Depositary for the Offer and either deliver the certificates for such Shares to the Depositary for the Offer along with the Letter of Transmittal (or a facsimile thereof), deliver such Shares pursuant to the procedures for book-entry transfers set forth in Section 3 of this Offer to Purchase or, if applicable, deliver such Shares pursuant to the procedures for Shares held in the Company's Employee Stock Ownership Plan as set forth in Section 3 of this Offer to Purchase, or (2) request your broker, dealer, commercial bank, trust company or other nominee to effect the transaction for you. If you have Shares registered in the name of a broker, dealer, commercial bank, trust company or other nominee, you must contact such broker, dealer, commercial bank, trust company or other nominee if you desire to tender your Shares.

        A stockholder who desires to tender such stockholder's Shares and whose certificates representing such Shares are not immediately available or who cannot comply with the procedures for book-entry transfer on a timely basis may tender such Shares by following the procedures for guaranteed delivery set forth in Section 3.

        Any questions and requests for assistance may be directed to the Information Agent or the Dealer Manager at their respective addresses and telephone numbers set forth on the back cover of this Offer to Purchase. Additional copies of this Offer to Purchase, the Letter of Transmittal, the Notice of Guaranteed Delivery and other related materials may be obtained from the Information Agent.

        THIS OFFER TO PURCHASE AND THE RELATED LETTER OF TRANSMITTAL CONTAIN IMPORTANT INFORMATION AND YOU SHOULD READ BOTH CAREFULLY AND IN THEIR ENTIRETY BEFORE MAKING A DECISION WITH RESPECT TO THE OFFER.

TABLE OF CONTENTS

		Page
SUMMARY TERM SHEET		1
INTRODUCTION		7
THE OFFER		14
1.	TERMS OF THE OFFER; EXPIRATION DATE.	14
2.	ACCEPTANCE FOR PAYMENT AND PAYMENT.	16
3.	PROCEDURES FOR ACCEPTING THE OFFER AND TENDERING SHARES.	18
4.	WITHDRAWAL RIGHTS.	21
5.	CERTAIN MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE OFFER AND THE PROPOSED MERGER.	22
6.	PRICE RANGE OF THE SHARES.	24
7.	EFFECT OF THE OFFER ON THE MARKET FOR THE SHARES; NYSE LISTING; MARGIN REGULATIONS; EXCHANGE ACT REGISTRATION.	24
8.	CERTAIN INFORMATION CONCERNING THE COMPANY.	25
9.	CERTAIN INFORMATION CONCERNING THE PURCHASER AND ITS AFFILIATES.	26
10.	BACKGROUND OF THE OFFER; CONTACTS WITH THE COMPANY.	28
11.	PURPOSE OF THE OFFER; PLANS FOR THE COMPANY; STATE ANTI-TAKEOVER LAWS.	41
12.	SOURCE AND AMOUNT OF FUNDS.	46
13.	DIVIDENDS AND DISTRIBUTIONS.	47
14.	CERTAIN CONDITIONS TO THE OFFER.	48
15.	CERTAIN LEGAL MATTERS; REQUIRED REGULATORY APPROVALS.	52
16.	CERTAIN FEES AND EXPENSES.	53
17.	MISCELLANEOUS.	54
SCHEDULE I
Directors and Executive Officers of the Purchaser and the Parent and Directors, Officers and General Partners of Certain Affiliates		I-1
SCHEDULE II
Transactions by the Purchaser's Affiliates Involving Company Shares		II-1

i

SUMMARY TERM SHEET

        This summary term sheet is a brief summary of the material provisions of the offer to purchase (the "Offer to Purchase") all the outstanding shares of common stock, par value $1.00 per share (the "Common Stock" or the "Shares") of ElkCorp, a Delaware corporation (the "Company") being made by BMCA Acquisition Sub Inc. (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), and is meant to help you understand the offer. This summary term sheet is not meant to be a substitute for the information contained in the remainder of this Offer to Purchase, and you should carefully read the fuller terms, descriptions and explanations contained in this Offer to Purchase and in the related Letter of Transmittal. The following are some of the questions you, as a stockholder of the Company, may have and answers to those questions. You are urged to carefully read this entire Offer to Purchase and the related Letter of Transmittal (which, together with any amendments or supplements thereto, constitute the "Offer") before making any decision on whether to tender your Shares.

        Unless the context requires otherwise, all references in this Summary Term Sheet to "Purchaser," "we," "us," or "our" are to BMCA Acquisition Sub Inc.

Who is offering to purchase my Shares of the Company's Common Stock?

•

We are a Delaware corporation formed for the purpose of making a tender offer for your outstanding shares of common stock of the Company, and we have carried on no activities other than in connection with making the tender offer. We are a wholly-owned subsidiary of the Parent.



•

The Parent is a Delaware corporation formed for the purpose of facilitating the Purchaser's tender offer for your outstanding shares of common stock of the Company, and has carried on no activities other than in connection with facilitating the tender offer. The Parent is a wholly-owned subsidiary of BMCA. BMCA is a leading national manufacturer and marketer of a broad line of asphalt and polymer based roofing products and accessories for the residential and commercial roofing markets. BMCA also manufactures specialty building products and accessories for the professional and do-it-yourself remodeling and residential construction industries. BMCA was incorporated under the laws of Delaware in 1994.



•

See Section 9 for more information on us and our affiliates.

What are we seeking to purchase, at what price, and do I have to pay any brokerage or similar fees to tender?

•

We are offering to purchase all of the Shares (and associated Series A Participating Preferred Stock purchase rights, referred to herein as "Rights") at a price of $42.00 net per Share in cash (subject to applicable withholding taxes) (the "Offer Price"), without interest, upon the terms and subject to the conditions contained in this Offer to Purchase and in the related Letter of Transmittal. The proposed price of $42.00 per Share represents an approximate 67% premium over the Company's closing price on November 3, 2006 ($25.18 per Share), the trading day immediately preceding the filing of BMCA's Schedule 13D announcing its beneficial ownership of 10.36% of the outstanding Shares and the Company's announcement of its sale process.



•

If you are the record owner of your Shares and you tender your Shares to us in the Offer, you will not have to pay any brokerage or similar fees. However, if you own your Shares through a broker or other nominee, your broker or nominee may charge you a fee to tender. You should consult your broker or nominee to determine whether any charges will apply.



•

See the Introduction and Section 16 for more information.

1

Why are we making the Offer?

•

We are making the Offer because we want to acquire control of, and the entire equity interest in, the Company. If the Offer is consummated, the Parent intends, as soon as practicable after consummation of the Offer, to have the Company consummate a second step merger (the "Proposed Merger") with us pursuant to which each then outstanding Share (other than Shares held by us) would be converted into the right to receive an amount in cash per share equal to the highest price per share paid by us pursuant to the Offer, without interest.



•

BMCA previously made an offer to purchase the Shares for $40.00 net per Share directly to the Company's stockholders. The Company recommended that its stockholders reject that offer and proceeded to amend and restate its merger agreement with affiliates of The Carlyle Group. In light of these events, BMCA decided, consistent with the two-step transaction structure in the merger agreement that BMCA has been negotiating with the Company, to have the Purchaser make this Offer directly to the Company's stockholders.



•

See the Introduction and Section 11 for more information.

What are the "Rights" and why are they important?

•

The Rights were issued to all of the Company's stockholders, but currently are not represented by separate certificates. Instead, they are currently represented by the certificates for your Shares. Unless the Rights are distributed to stockholders, a tender of Shares will include a tender of the related Rights. If the Rights are distributed, separate certificates representing the Rights will be issued and a holder will need to tender one Right with each Share tendered.



•

The completion of the Offer is conditioned upon, among other things, the Rights issued under the Company's Shareholder Rights Plan having been redeemed by the Board of Directors of the Company (the "Company Board"), or the Purchaser being satisfied, in its reasonable discretion, that the Rights are invalid or otherwise inapplicable to the Offer. The Company Board can satisfy this condition, prior to the expiration of the Offer, by amending the Company's Shareholder Rights Plan to render the Rights inapplicable to the Offer and the Proposed Merger or by acting to redeem the Rights. If the Company's Board does not take action to satisfy this condition, the Purchaser would suffer unacceptable dilution of its interest in the Company were the Purchaser to proceed to complete its purchase of Shares. For this reason, we will not purchase Shares under the Offer unless the Rights are redeemed or otherwise made inapplicable to us.



•

See Sections 3 and 11 for more information.

If I tender my Shares, will I continue to receive cash dividends declared and paid by the Company?

•

If you validly tender your Shares to the depositary as described below, you will still retain ownership of your Shares until such time as the Offer is successfully consummated and we accept your Shares for payment. As a result, until such time as the Offer is successfully completed, you will still be entitled to receive any cash dividends applicable to your Shares that the Company declares and pays prior to such completion. If the Company declares or pays any cash dividend or other distribution on the Shares on or after the date of this Offer to Purchase (except for regular quarterly cash dividends on the Shares not in excess of $0.05 per share having customary and usual record dates and payments) or makes certain other distributions, we may make certain adjustments to the Offer Price or take other specified actions. See Section 13 for more information.

2

How long do I have to decide whether to tender into the Offer?

•

You have until the expiration of the Offer to tender your Shares. The Offer currently is scheduled to expire at 12:00 Midnight, New York City time, on Wednesday, February 14, 2007. If the Offer is extended, we will issue a press release announcing the extension on or before 9:00 a.m., New York City time, on the first business day following the date the Offer was scheduled to expire.



•

The Offer may also be extended through a subsequent offering period (a "Subsequent Offering Period") after the completion of a purchase of Shares tendered in the Offer. A Subsequent Offering Period is an additional period of time beginning after we have completed the purchase of Shares tendered during the Offer, during which stockholders may tender, but not withdraw, their Shares and receive the Offer consideration. We do not currently intend to provide a Subsequent Offering Period.



•

See Section 1 for more information.

What are the conditions to the Offer?

•

The conditions to the Offer are:



•

There being validly tendered and not withdrawn prior to the expiration of the Offer 9,149,284 Shares, which represents approximately 40.6% of the Shares outstanding on a fully diluted basis (including, without limitation, all Shares issuable upon the exercise of any options warrants, or rights (other than the Rights)), that, when added to the 2,123,800 Shares, which represents approximately 9.4% of the Shares outstanding on a fully diluted basis, already beneficially owned by BMCA, shall constitute a majority of the Shares outstanding on a fully diluted basis on the date the Offer expires (the "Minimum Tender Condition");



•

Our being satisfied, in our reasonable discretion, that, after consummation of the Offer, Section 203 of the Delaware General Corporation Law, as amended (the "DGCL"), will not prohibit for any period of time, or impose any stockholder approval requirement with respect to, the proposed second step merger or any other business combination involving the Company and the Purchaser (the "Section 203 Condition");



•

The Rights issued under the Company's Shareholder Rights Plan having been redeemed by the Company Board, or our being satisfied, in our reasonable discretion, that the Rights are invalid or otherwise inapplicable to the Offer and the Proposed Merger (the "Rights Condition");



•

Our being satisfied, in our reasonable discretion, that the Offer and the merger have been approved for purposes of Article Thirteenth, or that the provisions of Article Thirteenth are otherwise inapplicable to the Offer and the merger (the "Article Thirteenth Condition"); and



•

The absence of certain events and conditions described in Section 14 of this Offer to Purchase.



•

More information on the conditions to the consummation of the Offer may be found in the Introduction and Section 14. We can waive any and all of the conditions to the Offer without the consent of the Company or any of its stockholders.



•

As discussed in more detail in the Introduction, the Company Board has the ability to satisfy the principal conditions to the Offer (with the exception of the Minimum Tender Condition), including the Section 203 Condition, the Rights Condition and the Article Thirteenth Condition.

3

We believe that the Company Board should take all necessary actions to satisfy these conditions, and we hereby request that they take such actions and refrain from any action that might obstruct the consummation of the Offer. Although we believe that, under the circumstances of the Offer, the Company Board should do so, there can be no assurance that the Company Board will act to satisfy the conditions to the Offer. If the Company Board does not act to satisfy the conditions to the Offer, we will not be able to consummate the Offer.

Do we have the financial resources to pay the purchase price in the Offer?

•

Yes. The Offer is not subject to any financing condition. We have obtained financing commitments from Deutsche Bank, Bear Stearns and JPMorgan Securities to fund the purchase of the Shares in the Offer. See Section 12 for more information.

Can I tender Shares I hold indirectly through the Company's Employee Stock Ownership Plan?

•

Yes. Participants in the Company's Employee Stock Ownership Plan (the "ESOP") are eligible to tender shares they hold indirectly in the ESOP. A Trustee Direction Form must be completed and received by the Trustee of the ESOP at least three business days before the expiration of the Offer. See Section 3 for more information.

How do I accept the Offer and tender my Shares?

•

To tender your Shares, you must deliver the certificates representing your Shares, together with a completed Letter of Transmittal and any other documents required by the Letter of Transmittal, to The Bank of New York, the depositary for the Offer, not later than the time the Offer expires. If your Shares are held in street name (i.e., through a broker, dealer or other nominee), the Shares can be tendered by your nominee through The Depository Trust Company. If you hold your Shares through the ESOP, you must complete a Trustee Direction Form and such form must be received by the Trustee of the ESOP at least three business days before the expiration of the Offer. If you are unable to deliver any required document or instrument to the depositary by the expiration of the Offer, you may gain some extra time by having a broker, a bank or other fiduciary that is an eligible institution guarantee that the missing items will be received by the depositary within three New York Stock Exchange trading days. For the tender to be valid, however, the depositary must receive the missing items within that three trading-day period. See Section 3 for more information.



•

Under this Offer, unless the Rights have been redeemed, or the Company's Shareholder Rights Plan is invalid or otherwise inapplicable to the Offer (determinations which are in the authority and complete discretion of the Company Board), stockholders are required to tender one Right for each Share tendered in order to effect a valid tender of the Share. If the Distribution Date (as defined in the Introduction under the caption "Rights Condition (Poison Pill)") does not occur before the expiration of the Offer, a tender of Shares in this Offer will automatically constitute a tender of the associated Rights. If the Distribution Date has occurred, the certificates evidencing the Rights (which will be issued by the Company if the Distribution Date occurs) will have to be tendered along with the certificates evidencing the Shares tendered. Please see the Introduction and Section 11 for more information.

If I accept the Offer, when will I get paid?

•

If the conditions to the Offer as set forth in the Introduction and Section 14 are satisfied or waived and we consummate the Offer and accept your Shares for payment, you will receive a check in an amount equal to the number of Shares you tendered multiplied by $42.00 (subject to

4

adjustment for applicable withholding taxes), promptly following expiration of the Offer. See Section 2 for more information.

Can I withdraw my previously tendered Shares?

•

You may withdraw all or a portion of your tendered Shares by delivering written, telegraphic or facsimile notice to the depositary prior to the expiration of the Offer. Further, if we have not agreed to accept your Shares for payment within 60 days of the commencement of the Offer, you can withdraw them at any time after that 60-day period until we do accept your Shares for payment. Once Shares are accepted for payment, they cannot be withdrawn. See Section 4 for more information.



•

We currently do not intend to provide a Subsequent Offering Period following the Offer. In the event that we subsequently elect to provide a Subsequent Offering Period, no withdrawal rights will apply to Shares tendered during such Subsequent Offering Period or to Shares tendered in the Offer and accepted for payment. See Section 1 for more information.

What does the board of directors of the Company think of the Offer?

•

Within ten business days after the date of this Offer to Purchase, the Company is required by law to publish, send or give to you (and file with the Securities and Exchange Commission (the "Commission")) a statement as to whether it recommends acceptance or rejection of the Offer, that it has no opinion with respect to the Offer or that it is unable to take a position with respect to the Offer. See Section 10 for more information.

If I do not tender but the Offer is successful, what will happen to my Shares?

•

As indicated above, if the Offer is consummated, the Parent intends, as soon as practicable following the consummation of the Offer, to have the Company consummate the Proposed Merger, under which all Shares that are not purchased in the Offer (other than Shares beneficially owned by BMCA) would be converted into the right to receive an amount in cash per Share equal to the highest price per Share paid by us in the Offer, without interest. If the Proposed Merger or similar business combination takes place, stockholders who do not tender in the Offer would receive the same amount of cash per Share that they would have received had they tendered their Shares in the Offer. See Section 7 for more information.



•

If the Offer is successfully consummated, there may be a significant delay before we can effect the Proposed Merger. During such time, we may choose to delist the Shares from the New York Stock Exchange and terminate the registration of the Shares under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). This could have an adverse impact on the market for the Shares prior to the Proposed Merger. See Section 7 for more information.

Are appraisal rights available in either the Offer or the Proposed Merger?

•

Appraisal rights are not available in the Offer. After the Offer, if the Proposed Merger takes place, appraisal rights will be available to holders of Shares who do not vote in favor of the Proposed Merger, subject to and in accordance with Section 262 of DGCL. A holder of Shares must properly perfect its right to seek appraisal under Delaware law in connection with the Proposed Merger in order to exercise appraisal rights. The value you would receive if you perfect appraisal rights could be more or less than the prices per Share to be paid in the Proposed Merger. See Section 11 for more information.

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What are the U.S. federal income tax consequences of the Offer?

•

The receipt of cash by you in exchange for your Shares pursuant to the Offer or the proposed second step merger is a taxable transaction for U.S. federal income tax purposes and may also be a taxable transaction under applicable state, local or foreign tax laws. In general, you will recognize, for U.S. federal income tax purposes, capital gain or loss equal to the difference between your adjusted tax basis in the Shares surrendered and the amount of cash you receive for those Shares. You should consult your tax advisor on the tax implications of tendering your Shares. See Section 5 for more information.

What is the market value of my Shares as of a recent date?

•

The proposed price of $42.00 per Share represents an approximate 67% premium over the Company's closing price on November 3, 2006 ($25.18 per Share), the trading day immediately preceding the filing of BMCA's Schedule 13D announcing its beneficial ownership of more than 10% of the Shares and the Company's announcement of its sale process. You should obtain a recent quotation for your Shares before deciding whether or not to tender. See Section 6 for more information.

Whom can I call with questions?

•

You can call D. F. King & Co., Inc., our Information Agent, at (212) 269-5550 or (888) 628-9011 or Bear, Stearns & Co. Inc., our Dealer Manager, at (212) 272-5112 or (877) 696-BEAR with any questions you may have.

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To the Holders of Shares of Common Stock of ElkCorp:

INTRODUCTION

        BMCA Acquisition Sub Inc. (including any successor thereto, the "Purchaser"), a Delaware corporation, a wholly-owned subsidiary of BMCA Acquisition Inc. ("Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), hereby offers to purchase all the outstanding shares of common stock, par value $1.00 per share (the "Common Stock" or the "Shares"), of ElkCorp, a Delaware corporation (the "Company" or "Elk"), and the associated Series A Participating Preferred Stock purchase rights (the "Rights"), at a price of $42.00 per Share, net to the seller in cash (subject to applicable withholding taxes), without interest thereon (the "Offer Price"), upon the terms and subject to the conditions set forth in this Offer to Purchase and in the related Letter of Transmittal (which, together with any amendments or supplements thereto, constitute the "Offer").

        Currently, BMCA beneficially owns approximately 10% of the issued and outstanding Shares. On November 2, 2006, shortly after the acquisition of such Shares, Robert B. Tafaro, the Chief Executive Officer and President of BMCA, called Thomas D. Karol, Chairman of the Board and Chief Executive Officer of Elk to discuss BMCA's interest in a business combination between Elk and BMCA. During a call held on November 5, 2006, Elk informed BMCA that there was an on-going sale process that had been underway for some time. Although BMCA was never contacted as part of this process, Elk stated that BMCA would now be invited to participate and, subject to the execution of a standard confidentiality agreement, would be given access to the confidential information other bidders had received. Elk further indicated that it was expecting to complete the process by the end of November.

        A confidentiality and standstill agreement was provided by Elk shortly after the November 5^th call. The agreement contained restrictions which BMCA believed would have unreasonably tied BMCA's hands and prevented it from communicating an offer to the Board of Directors of Elk (the "Company Board" or the "Elk Board") or to stockholders in the event that Elk terminated its process prematurely or preferred a bidder who could not deliver as much value as BMCA. BMCA believed these provisions to be onerous and unreasonable in light of its significant investment in Elk.

        Over the next several weeks, BMCA and its advisors attempted to negotiate the confidentiality and standstill agreement with Elk and its advisors. Elk continued to insist that BMCA agree to an overly restrictive standstill and showed little or no flexibility in negotiating the standstill provisions. BMCA made clear that it preferred to receive confidential information, but reiterated that it could not enter into what BMCA believed was an onerous and unreasonable standstill. On November 15, 2006, without the benefit of Company confidential information, BMCA made an acquisition proposal to Elk pursuant to which BMCA offered to pay $35.00 per Share cash consideration for all outstanding Shares and indicated that it hoped to increase its offer price if given access to confidential information provided to other bidders.

        On Monday, December 11, 2006, BMCA announced that it had obtained committed financing from Deutsche Bank and Bear Stearns sufficient to fund the full price of the acquisition. During that week, BMCA again contacted Elk and UBS, investment bankers for Elk, on multiple occasions to seek guidance as to how Elk wished BMCA to proceed with its proposal. On Tuesday, December 12, 2006, UBS informed BMCA that its merger proposal was scheduled to be considered at an Elk Board Meeting on December 13^th and that UBS would be in a position to provide BMCA with guidance in a call immediately after the meeting. UBS and Elk did not provide any guidance or return BMCA's calls following the Board Meeting.

        On December 17, 2006, BMCA sent Elk a letter reiterating its offer and indicating its intention to commence a tender offer. On the morning of December 18, 2006, Elk's legal counsel emailed BMCA at approximately 4 a.m. seeking to persuade BMCA to defer making its tender offer. Later that morning, without notice to BMCA and without affording it an opportunity to increase its offer, Elk

7

announced that it had entered into a definitive agreement with affiliates of The Carlyle Group to acquire Elk in a leveraged buyout involving management participation at $38.00 per Share in cash. During the evening of December 18, 2006, BMCA submitted a letter to the Elk Board announcing its intention to commence a tender offer providing $40.00 net per Share cash consideration for all outstanding Shares. When Elk did not respond to this offer, BMCA launched its tender offer on December 20, 2006.

        Pursuant to Elk's expressed interest in a negotiated merger, on December 24, 2006, counsel to BMCA delivered a draft merger agreement to Elk's counsel, which was superior to the Carlyle merger agreement in both timing and price and, BMCA believes, was at least as strong as the Carlyle agreement with regard to every other provision. BMCA reiterated its request for access to reasonable due diligence information that was, at the very least, substantially the same as the due diligence provided to other bidders. Finally, after almost two months of negotiations, BMCA and Elk entered into a confidentiality and standstill agreement on December 29, 2006, in which Elk agreed to provide such due diligence. Even with this agreement, the due diligence process was frustratingly slow and continued to be managed by Elk's Chief Executive Officer who will be a participant in the competing Carlyle transaction.

        On January 8, 2007, Elk filed its Schedule 14D-9 (the "Schedule 14D-9"), in which it recommended that its stockholders reject BMCA's $40 per Share offer and made numerous inaccurate statements with respect to the offer. On January 9, 2007, BMCA sent a letter to the Special Committee of the Elk Board responding to those inaccuracies and reiterating its commitment to work towards a negotiated transaction.

        On Friday January 12, 2007, after substantial discussions, representatives of BMCA communicated to Elk's counsel that BMCA would be sending a revised draft merger agreement and revised financing commitment letters reflecting compromises resulting from the considerable negotiations that had occurred between Elk's and BMCA's advisors. The revised financing commitments, disclosed in connection with this Offer, are now in the form Elk requested.

        During the holiday weekend of January 13, 2007, representatives of Elk and BMCA and their advisors had various discussions regarding due diligence and the contents of BMCA's revised proposal. On Tuesday, January 16, 2007, without contacting BMCA regarding its revised proposal, Elk attempted to prematurely terminate its auction by announcing that it had amended its merger agreement with affiliates of The Carlyle Group such that those affiliates would now pay $40.50 per Share and would launch a tender offer on January 18, 2007. In addition, on January 16, 2007, Elk terminated BMCA's access to due diligence. Counsel to BMCA informed Elk's counsel on that same day that BMCA was considering whether it would increase its offer, and expressed BMCA's interest in completing the already commenced diligence with that goal in mind.

        BMCA received no response to that request and decided, consistent with the two-step transaction structure in the merger agreement that BMCA has been negotiating with Elk, to have the Purchaser make this Offer directly to the Company's stockholders.

        This tender offer is not conditioned on due diligence and provides Elk stockholders the opportunity to realize higher value for their Shares than the Carlyle agreement. The Offer is, however, subject to a number of conditions that would be narrowed or eliminated if BMCA is allowed to complete due diligence and deliver an effective negotiated merger agreement.

        In connection with the filing of the Offer, BMCA sent a letter to Elk's Special Committee in which it urged that the due diligence process be resumed so as to enable the Purchaser to release various conditions to its Offer, which it will do upon satisfactory completion of due diligence.

        The purpose of the Offer is for BMCA, through the Parent and the Purchaser, to acquire control of Elk. If the Offer is consummated, the Parent intends to have Elk consummate the second step merger with the Purchaser (the "Proposed Merger"), as soon as practicable after consummation of the

8

Offer, pursuant to which each then outstanding Share (other than Shares beneficially owned by BMCA) would be converted into the right to receive an amount in cash per Share equal to the highest price per Share paid by the Purchaser pursuant to the Offer, without interest.

        BMCA is a leading national manufacturer and marketer of a broad line of asphalt and polymer based roofing products and accessories for the residential and commercial roofing markets. BMCA also manufactures specialty building products and accessories for the professional and do-it-yourself remodeling and residential construction industries. BMCA was incorporated under the laws of Delaware in 1994. Each of the Parent and the Purchaser was incorporated under the laws of Delaware in 2006. The Purchaser is affiliated with Heyman Investment Associates Limited Partnership ("HIA") through Samuel J. Heyman. Mr. Heyman is the sole general partner of HIA and of Heyman Holdings Associates Limited Partnership, the Purchaser's indirect parent.

        Tendering stockholders who are record owners of their Shares and tender directly to the Depositary (as defined below) will not be obligated to pay brokerage fees or commissions or, except as otherwise provided in Instruction 7 of the Letter of Transmittal, stock transfer taxes with respect to the purchase of Shares by the Purchaser under the Offer. Stockholders who hold their Shares through a broker or bank should consult such institution as to whether it charges any service fees. Tendering stockholders who own their Shares through Elk's Employee Stock Ownership Plan (the "ESOP") must complete a Trustee Direction Form and deliver such form to the Trustee of the ESOP. The Trustee of the ESOP will then tender Shares, as directed, directly to the Depositary. BMCA will pay all charges and expenses of Bear, Stearns & Co. Inc., as dealer manager (the "Dealer Manager"), The Bank of New York, as depositary (the "Depositary") and D. F. King & Co., Inc., as information agent (the "Information Agent"), incurred in connection with the Offer. See Section 16 for more information.

        There are substantial conditions to consummation of the Offer, among them the Section 203 Condition, the Rights Condition and the Article Thirteenth Condition. If Elk's Board of Directors opposes the Offer, certain provisions of the Delaware General Corporation Law, as amended (the "DGCL"), and Elk's Restated Articles of Incorporation (as amended, the "Charter") and By-Laws (as amended, the "By-Laws") would affect the Purchaser's ability to obtain control of Elk and to effect the Proposed Merger.

        The timing and details of the consummation of the Offer and the Proposed Merger depend on a variety of factors and legal requirements, the number of Shares (if any) acquired by the Purchaser pursuant to the Offer, and most importantly, actions of the Elk Board. Although the Purchaser intends to have Elk consummate the Proposed Merger as soon as practicable after consummation of the Offer, because the Proposed Merger must be approved by the Elk Board, the Proposed Merger could be delayed for a substantial period of time if the Elk Board refuses to approve the Proposed Merger, or if a majority of the members of the Elk Board refuse to resign in favor of designees of the Purchaser. There can be no assurance that the Purchaser will be able to consummate the Offer or, if the Offer is consummated, that the Purchaser will be able to effectuate the Proposed Merger. See below and Section 14 for more information.

THE SATISFACTION OF THE PRINCIPAL CONDITIONS TO THE OFFER (EXCEPT FOR THE MINIMUM TENDER CONDITION) IS WITHIN THE CONTROL OF THE ELK BOARD. UNLESS THE ELK BOARD ACTS TO REMOVE THE IMPEDIMENTS TO THE CONSUMMATION OF THE OFFER, THE PURCHASER WILL NOT BE ABLE TO CONSUMMATE THE OFFER.

        THE PARENT AND THE PURCHASER ARE SEEKING TO NEGOTIATE WITH ELK WITH RESPECT TO THE BUSINESS COMBINATION BETWEEN THE PURCHASER AND ELK. THE PURCHASER RESERVES THE RIGHT TO AMEND THE OFFER (INCLUDING AMENDING THE NUMBER OF SHARES TO BE PURCHASED AND THE OFFER PRICE (AS DEFINED HEREIN)) UPON ENTERING INTO A MERGER AGREEMENT WITH ELK, OR TO NEGOTIATE A MERGER AGREEMENT WITH ELK. SUCH A MERGER AGREEMENT COULD INVOLVE, AMONG OTHER POSSIBILITIES, TERMINATING THE OFFER AND

9

CONVERTING THE SHARES, UPON CONSUMMATION OF SUCH MERGER, INTO CASH AND/OR OTHER CONSIDERATION IN SUCH AMOUNTS AS ARE NEGOTIATED BY THE PURCHASER AND ELK.

The Offer does not constitute a solicitation of proxies for any meeting of Elk's stockholders. Any such solicitation by the Purchaser or any of its affiliates would be made only pursuant to separate proxy materials complying with the requirements of Section 14(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act").

Certain Conditions to the Offer

        The Offer is subject to the fulfillment of certain conditions, including the following:

        Minimum Tender Condition.    Consummation of the Offer is conditioned upon there being validly tendered and not withdrawn prior to the expiration of the Offer such number of Shares of the Company that, when added to the Shares already beneficially owned by BMCA, shall constitute a majority of the Shares outstanding on a fully diluted basis (including, without limitation, all Shares issuable upon the exercise of any options, warrants, or rights (other than the Rights)) (the "Minimum Tender Condition").

        As of the date hereof, the Purchaser's affiliate, HIA, owns 2,123,799 Shares and the Purchaser owns one Share. According to the Schedule 14D-9, as of January 5, 2007, there were (i) 20,624,468 Shares issued and outstanding, (ii) 1,339,999 Shares issuable under outstanding stock options and (iii) 581,700 Shares subject to outstanding performance share awards. Based on the foregoing and assuming that (a) no Shares are issued, required to be issued, or acquired by the Company after January 5, 2007 (other than as described in clause (d) below), (b) no options were granted or expire after January 5, 2007, (c) no performance share awards were granted after January 5, 2007, (d) all 1,339,999 Shares subject to issuance under the Company's stock option plan are issued at or prior to the consummation of the Offer and (e) all 581,700 Shares subject to outstanding performance share awards are issued at or prior to the consummation of the Offer, there would be 22,546,167 Shares outstanding immediately following consummation of the Offer, and, as a result, the Minimum Tender Condition would be satisfied if the Purchaser acquired 9,149,284 Shares in addition to the 2,123,800 Shares already beneficially owned by BMCA.

        Section 203 Condition.    Consummation of the Offer is conditioned upon the Purchaser being satisfied, in its reasonable discretion, that Section 203 of the DGCL will not prohibit for any period of time, or impose any stockholder approval requirement with respect to, the Proposed Merger or any other "Business Combination" (as defined in the DGCL) involving the Company and the Purchaser or any of its affiliates (the "Section 203 Condition").

        Section 203 of the DGCL prohibits, for a three-year period following the time that a stockholder becomes a holder of 15% or more of a corporation's outstanding voting stock, certain types of transactions (including mergers or consolidations; sales, leases, exchanges or other transfers of 10% or more of the aggregate assets of the corporation; issuances or transfers by a corporation of any stock of the corporation which would have the effect of increasing the stockholder's proportionate share of the stock of any class or series of the corporation; and other transactions listed therein) between the corporation and the 15% stockholder unless certain conditions are met. These conditions include: (i) if the proposed transaction or series of transactions by which the 15% stockholder became such is approved by the board of directors of the corporation prior to the date the stockholder became a 15% stockholder, or (ii) if, upon consummation of the transaction or series of transactions whereby the stockholder became a 15% stockholder, the stockholder owns at least 85% of the outstanding voting stock of the corporation without regard to the shares owned by the corporation's officers and directors or shares owned through certain employee stock plans.

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        "Business Combinations", as such term is defined under Section 203, are also permitted during the three-year period following the time that a stockholder becomes a holder of 15% or more of a corporation's outstanding voting stock if approved by the corporation's board of directors and, at an annual or special meeting of stockholders, by the holders of at least 66²/3% of the outstanding voting stock not owned by the 15% stockholder.

        A corporation, by action of its board of directors, may adopt an amendment to its bylaws, electing not to be governed by Section 203, which amendment may not be further amended by the board of directors. In addition, the corporation, by action of its stockholders, may adopt an amendment to its charter or bylaws, electing not to be governed by Section 203, provided that such amendment must be approved by a majority of the shares entitled to vote. With respect to the latter situation, such amendment will be effective immediately in the case of a corporation that (i) has never had a class of voting stock listed on a national securities exchange, authorized for quotation on the NASDAQ Stock Market or held of record by more than 2,000 stockholders; and (ii) has not elected to be governed by Section 203 in its charter. In all other cases, such amendment will not be effective until 12 months after the adoption of such amendment and will not apply to any Business Combination between the corporation and any "Interested Stockholder" (as defined in the DGCL) on or prior to such adoption. A bylaw amendment adopted pursuant to this section may not be further amended by the board of directors.

        The Purchaser believes that it, together with its affiliates, would collectively be deemed to be an "Interested Stockholder" for purposes of the DGCL upon consummation of the Offer (unless it acquired in excess of 85% of the outstanding Common Stock) and that, accordingly, unless the Company Board acts to exempt the Offer and the Proposed Merger from Section 203 of the DGCL prior to consummation of the Offer or the Company's charter or bylaws are amended in accordance with the conditions described above, the DGCL would prohibit consummation of the Proposed Merger for a period of three years.

The Company Board can satisfy the Section 203 Condition by adopting a resolution providing that the Company will not be subject to Section 203 of the DGCL or that the Proposed Merger would be exempt therefrom. The Purchaser believes that the Company Board should adopt such a resolution and hereby requests that they do so. If the Company Board does not exempt the Company or the Proposed Merger from Section 203 of the DGCL, it is likely that the Section 203 Condition will not be satisfied and it is likely that the Purchaser will not consummate the Offer because it will be unable to consummate the Proposed Merger, unless the number of Shares tendered, in conjunction with the Shares beneficially owned by the Purchaser, equals at least 85%.

        The Purchaser also reserves its right to challenge the applicability of Section 203 of the DGCL to the Company and/or the validity of any purported application thereof in order to remove this impediment to the consummation of the Offer.

        Rights Condition (Poison Pill).    Consummation of the Offer is conditioned upon the Purchaser being satisfied, in its reasonable discretion, that the Rights issued under the Company's Shareholder Rights Plan are invalid or otherwise inapplicable to the Offer and the Proposed Merger or the Rights having been redeemed by the Company Board (the "Rights Condition").

        The Rights Condition is significant to the Offer because if the Purchaser were to purchase Shares under the Offer and the Rights were triggered by such purchase, each Right would entitle its holder, other than the Purchaser and its affiliates or associates, to purchase, upon payment of the applicable exercise price, preferred stock of the Company or Common Stock of the Company at a discount. If after a triggering event the Company merges, consolidates or engages in a similar transaction in which the Company does not survive, each Right-holder would also have the right to buy discounted stock in the surviving entity. Any of these circumstances would result in the Purchaser suffering unacceptable dilution of its interest in the Company.

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        Shortly after the Company was informed by BMCA that it had acquired beneficial ownership of more than 10% of the Company's Common Stock, the Company amended its Shareholder Rights Plan to decrease, from 15% to 10%, the percentage of beneficial ownership of the Company's Common Stock that triggers the separation of the Rights from the Common Stock and the exercisability thereof.

        Until the occurrence of certain triggering events, the Rights are represented by, and trade in tandem with, the Common Stock. As amended, the Company's Shareholders Rights Plan provides that the Rights separate from the Common Stock and become exercisable upon either (i) the close of business on the tenth day after the first date of public announcement that a person or group has acquired beneficial ownership of 10% or more of the Company's Common Stock (or, for persons having beneficial ownership of 10% or more of the Shares as of November 5, 2006, the time that such person acquires beneficial ownership of additional Shares after November 5, 2006), or (ii) the close of business on the tenth day after a tender or exchange offer has been launched by any person or group unaffiliated with the Company and who, by virtue of consummating the tender or exchange offer, would acquire beneficial ownership of 10% or more of the Company's Common Stock (or, for persons having beneficial ownership of 10% or more of the Shares as of November 5, 2006, would result in such person acquiring beneficial ownership of additional Shares after November 5, 2006) (the earlier of (i) and (ii) being herein referred to as the "Distribution Date"). Once the Rights have separated from the Common Stock, if the Company merges, consolidates or engages in a similar transaction in which the Company does not survive, each Right would entitle its holder to purchase discounted stock in the surviving entity.

        The Company Board may amend or supplement the Company's Shareholder Rights Plan at any time prior to the time that any person or group becomes an "Acquiring Person," meaning the person has become the beneficial owner of 10% or more of the Company's Common Stock, or, for persons having beneficial ownership of 10% or more of the Shares as of November 5, 2006, the person acquires any additional Shares. The Company Board may also, at its option, redeem all of the outstanding Rights at a price of $0.01 per Right so long as no person or group has become an Acquiring Person. In connection with the Offer, unless the Company's Shareholder Rights Plan is amended or otherwise rendered inapplicable to the Offer, or the Rights have been redeemed, either of which is in the complete discretion of the Company Board, stockholders are required to tender one Right for each Share tendered in order to effect a valid tender of the Shares. If the Distribution Date does not occur before the Expiration Date, a tender of Shares in this Offer will automatically constitute a tender of the associated Rights. If the Distribution Date has occurred, the certificates representing the Rights will have to be tendered along with the certificates evidencing the Shares tendered.

        At its meeting on January 7, 2007, the Company Board took action, as permitted by the Company's Shareholder Rights Plan, to postpone the Distribution Date. Until the Distribution Date, the Rights will continue to be evidenced by the certificates for the Shares, and the Rights will be transferable only in connection with the transfer of the associated Shares.

The Company Board can satisfy the Rights Condition by amending the Company's Shareholder Rights Plan to render the Rights inapplicable to the Offer and the Proposed Merger or by acting to redeem the Rights. The Purchaser believes that the Company Board should take such action or make such amendment and hereby requests that they do so. If the Company Board does not act to make the Company's Shareholder Rights Plan inapplicable to the Offer and Proposed Merger, the Purchaser would suffer unacceptable dilution of its interest in the Company were the Purchaser to purchase Shares under the Offer and it is likely that the Purchaser would not consummate the Offer.

        Article Thirteenth Condition.    Consummation of the Offer is conditioned upon the Purchaser being satisfied, in its reasonable discretion, that the Offer and the Proposed Merger have been approved for purposes of Article Thirteenth of the Charter, or that the provisions of Article Thirteenth are otherwise inapplicable to the Offer and the Proposed Merger (the "Article Thirteenth Condition").

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        Pursuant to Article Thirteen of the Charter, the Purchaser will become a "Related Person" at the time it acquires more than 20% of the outstanding common stock. Once it is a Related Person, any "Business Combination" between the Company and the Purchaser or its affiliates must be approved by the affirmative votes of (i) the holders of not less than 80% of the outstanding Shares, and (ii) the affirmative vote of the holders of not less than 67% of the outstanding Shares held by persons other than the "Related Person."

        The 80%/67% voting restrictions applicable to a Related Person will not be triggered by the following situations:

(1)

The continuing directors of the Company have, by a ²/3 vote, either expressly approved (in advance) the acquisition of outstanding shares of Common Stock that caused the Related Person to become a Related Person, or have approved the Business Combination, if at the time of such approval the continuing directors were a majority of the Board; or



(2)

The Business Combination is a merger or consolidation for which a proxy statement (complying with the Exchange Act) is to be mailed to the stockholders of the Company for the purpose of soliciting their approval for the transaction, and the following two conditions are met: (A) the cash or fair market value of the consideration to be received by the Company's stockholders is not less than the higher of the highest price per share of Common Stock paid by the Related Person in acquiring any of the Company's Common Stock or the market price of the Common Stock valued as of the latest practicable date prior to the mailing of the proxy statement; and (B) the proxy statement mailed to stockholders meets certain criteria, including the recommendation (whether positive or negative) of the Company Board and the opinion of a reputable financial advisor.

The Company Board can satisfy the Article Thirteenth Condition by adopting a resolution approved by more than ²/3 of the directors of the Company approving the acquisition of additional Shares by the Purchaser pursuant to this Offer to Purchase and the Proposed Merger. The Purchaser believes that the Company Board should adopt such a resolution and hereby requests that they do so. If the Company Board does not authorize the acquisition of Shares pursuant to this Offer to Purchase, it is likely that the Article Thirteenth Condition will not be satisfied and it is likely that the Purchaser will not consummate the Offer because it will be unable to consummate the Proposed Merger.

        CERTAIN OTHER CONDITIONS TO THE CONSUMMATION OF THE OFFER ARE DESCRIBED IN SECTION 14. THE PURCHASER RESERVES THE RIGHT (SUBJECT TO THE APPLICABLE RULES AND REGULATIONS OF THE COMMISSION) TO AMEND OR WAIVE ANY ONE OR MORE OF THE TERMS AND CONDITIONS OF THE OFFER. SEE SECTIONS 1, 11 AND 14 FOR MORE INFORMATION.

        THE OFFER IS NOT CONDITIONED ON THE PURCHASER OBTAINING FINANCING. SEE SECTION 12 FOR MORE INFORMATION.

If the Offer is not consummated, the Purchaser may acquire Shares through, among other things, open market purchases, privately negotiated transactions, a tender offer or exchange offer or otherwise, upon such terms and at such prices as it shall determine, which may be more or less than the price paid in the Offer. The Purchaser also reserves the right to dispose of Shares.

THIS OFFER TO PURCHASE AND THE RELATED LETTER OF TRANSMITTAL CONTAIN IMPORTANT INFORMATION WHICH SHOULD BE READ CAREFULLY BEFORE ANY DECISION IS MADE WITH RESPECT TO THE OFFER.

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THE OFFER

1.     TERMS OF THE OFFER; EXPIRATION DATE.

        Upon the terms and subject to the conditions of the Offer (including, if the Offer is extended or amended, the terms and conditions of any such extension or amendment), the Purchaser will accept for payment and pay for all Shares validly tendered and not withdrawn on or prior to the Expiration Date in accordance with the procedures set forth in Section 4. The term "Expiration Date" means 12:00 Midnight, New York City time, on Wednesday, February 14, 2007, unless and until the Purchaser, in its sole discretion, extends the period of time for which the Offer is open, in which event the term "Expiration Date" means the time and date at which the Offer, as so extended by the Purchaser, will expire.

        The Offer is conditioned upon satisfaction of the Minimum Tender Condition, the Section 203 Condition, the Rights Condition, the Article Thirteenth Condition and all the other conditions set forth in Section 14. The Purchaser reserves the right (but will not be obligated), subject to the applicable rules and regulations of the Commission, to amend or waive the Minimum Tender Condition or any other condition of the Offer. If the Minimum Tender Condition or any of the other conditions set forth in the Introduction or Section 14 has not been satisfied by 12:00 Midnight, New York City time, on Wednesday, February 14, 2007 (or any other time then set as the Expiration Date), the Purchaser may elect to:

        (1)   extend the Offer and, subject to applicable withdrawal rights, retain all tendered Shares until the expiration of the Offer, as extended;

        (2)   subject to complying with applicable rules and regulations of the Commission, waive all of the unsatisfied conditions and accept for payment and pay for all Shares tendered and not withdrawn prior to the expiration of the Offer; or

        (3)   terminate the Offer and not accept for payment or pay for any Shares and return all tendered Shares to tendering stockholders.

        The Purchaser expressly reserves the right (but will not be obligated), in its sole discretion, at any time and from time to time, to extend the period during which the Offer is open for any reason by giving oral or written notice of the extension to the Depositary and by making a public announcement of the extension. During any extension, all Shares previously tendered and not withdrawn will remain subject to the Offer and subject to the right of a tendering stockholder to withdraw Shares, as described in Section 4.

        Subject to any applicable rules and regulations of the Commission, including Rule 14e-1(c) under the Exchange Act, the Purchaser expressly reserves the right to:

        (1)   terminate or amend the Offer if any of the conditions referred to in the Introduction has not been satisfied or upon the occurrence of any of the other events specified in Section 14; or

        (2)   waive any condition or otherwise amend the Offer in any respect, in each case, by giving oral or written notice of such termination, waiver or amendment to the Depositary and by making a public announcement thereof, as described below.

        If the Purchaser extends the Offer or if the Purchaser is delayed in its acceptance for payment of or payment (whether before or after its acceptance for payment of Shares) for Shares, or it is unable to pay for Shares pursuant to the Offer for any reason, then, without prejudice to the Purchaser's rights under the Offer, the Depositary may retain tendered Shares on behalf of the Purchaser, and such Shares may not be withdrawn except to the extent tendering stockholders are entitled to withdrawal rights as described in Section 4. However, the Purchaser's ability to delay payment for Shares that the Purchaser has accepted for payment is limited by Rule 14e-1(c) under the Exchange Act, which requires that a bidder pay the consideration offered or return the securities deposited by or on behalf of stockholders promptly after the termination or withdrawal of the bidder's offer.

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        Any extension, delay, termination, waiver or amendment of the Offer will be followed as promptly as practicable by public announcement thereof, and such announcement in the case of an extension will be made no later than 9:00 a.m., New York City time, on the next business day after the previously scheduled Expiration Date. Without limiting the manner in which the Purchaser may choose to make any public announcement, subject to applicable law (including Rules 14d-4(d) and 14e-1(d) under the Exchange Act, which require that material changes be promptly disseminated to holders of Shares in a manner reasonably designed to inform such holders of such change), the Purchaser currently intends to make announcements regarding the Offer by issuing a press release.

        If the Purchaser makes a material change in the terms of the Offer, or if it waives a material condition to the Offer, the Purchaser will extend the Offer and disseminate additional tender offer materials to the extent required by Rules 14d-4(d)(1), 14d-6(c) and 14e-1 under the Exchange Act. The minimum period during which an Offer must remain open following material changes in the terms of the Offer, other than a change in price or a change in the percentage of securities sought or a change in any dealer's soliciting fee, will depend upon the facts and circumstances, including the materiality of the changes. In contrast, a minimum 10-business day period from the date of such change is generally required to allow for adequate dissemination of new information to stockholders in connection with a change in price or, subject to certain limitations, a change in the percentage of securities sought or a change in any dealer's soliciting fee. For purposes of the Offer, a "business day" means any day other than a Saturday, Sunday or a federal holiday, and consists of the time period from 12:01 a.m. through 12:00 Midnight, New York City time.

        If the Purchaser decides, in its sole discretion, to increase the consideration offered in the Offer to holders of Shares and if, at the time that notice of the increase is first published, sent or given to holders of Shares, the Offer is scheduled to expire at any time earlier than the expiration of a period ending on the tenth business day from, and including, the date that such notice is first so published, sent or given, then the Offer will be extended until at least the expiration of ten business days from the date the notice of the increase is first published, sent or given to holders of Shares.

        IF, ON OR BEFORE THE EXPIRATION DATE, THE PURCHASER INCREASES THE CONSIDERATION BEING PAID FOR SHARES ACCEPTED FOR PAYMENT PURSUANT TO THE OFFER, SUCH INCREASED CONSIDERATION WILL BE PAID TO ALL STOCKHOLDERS WHOSE SHARES ARE PURCHASED IN THE OFFER, WHETHER OR NOT SUCH SHARES WERE TENDERED BEFORE THE ANNOUNCEMENT OF THE INCREASE IN CONSIDERATION.

        Under Rule 14d-11 under the Exchange Act, the Purchaser may, subject to certain conditions, elect to provide a subsequent offering period of between three business days and 20 business days in length after the expiration of the Offer on the Expiration Date and acceptance for payment of the Shares tendered in the Offer (a "Subsequent Offering Period"). A Subsequent Offering Period would be an additional period of time, after completion of the first purchase of Shares in the Offer, during which stockholders would be able to tender Shares not tendered in the Offer.

        During a Subsequent Offering Period, tendering stockholders would not have withdrawal rights and the Purchaser would promptly purchase and pay for any Shares tendered at the same price paid in the Offer. Rule 14d-11 provides that the Purchaser may provide a Subsequent Offering Period so long as, among other things:

        (1)   the initial 20-business day period of the Offer has expired,

        (2)   the Purchaser offers the same form and amount of consideration for Shares in the Subsequent Offering Period as in the initial Offer,

        (3)   the Purchaser immediately accepts and promptly pays for all Shares tendered during the Offer prior to its expiration,

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        (4)   the Purchaser announces the results of the Offer, including the approximate number and percentage of Shares deposited in the Offer, no later than 9:00 a.m., New York City time, on the next business day after the Expiration Date and immediately begins the Subsequent Offering Period, and

        (5)   the Purchaser immediately accepts and promptly pays for Shares as they are tendered during the Subsequent Offering Period.

        If the Purchaser elects to include a Subsequent Offering Period, it will notify stockholders of the Company consistent with the requirements of the Commission.

        THE PURCHASER DOES NOT CURRENTLY INTEND TO INCLUDE A SUBSEQUENT OFFERING PERIOD IN THE OFFER. UNDER RULE 14d-7(a)(2) UNDER THE EXCHANGE ACT, IN THE EVENT THAT THE PURCHASER SUBSEQUENTLY ELECTS TO INCLUDE A SUBSEQUENT OFFERING PERIOD, NO WITHDRAWAL RIGHTS WOULD APPLY TO SHARES TENDERED DURING SUCH SUBSEQUENT OFFERING PERIOD AND NO WITHDRAWAL RIGHTS WOULD APPLY DURING SUCH SUBSEQUENT OFFERING PERIOD WITH RESPECT TO SHARES TENDERED IN THE OFFER AND ACCEPTED FOR PAYMENT. THE SAME CONSIDERATION WILL BE PAID TO STOCKHOLDERS TENDERING SHARES IN THE OFFER OR IN A SUBSEQUENT OFFERING PERIOD, IF ONE IS INCLUDED.

        A request is being made to the Company under Rule 14d-5 of the Exchange Act and under Section 220(b) of the DGCL for use of the Company's stockholder lists and security position listings for the purpose of disseminating the Offer to stockholders. Upon compliance by the Company with this request and receipt of these lists or listings from the Company, this Offer to Purchase, the Letter of Transmittal and all other relevant materials will be mailed to record holders of Shares and will be furnished to brokers, dealers, banks, trust companies and similar persons whose names, or the names of whose nominees, appear on the Company's stockholders lists, or, if applicable, who are listed as participants in a clearing agency's security position listing for subsequent transmittal to beneficial owners of Shares by the Purchaser. Alternatively, if the Company so elects, the materials will be mailed to stockholders by the Company.

        If any tendered Shares are not purchased under the Offer for any reason, or if share certificates are submitted representing more Shares than are tendered, certificates representing unpurchased or untendered Shares will be returned, without expense to the tendering stockholder (or, in the case of Shares delivered pursuant to the book-entry transfer procedures set forth in Section 3, such Shares will be credited to an account maintained within the Book-Entry Transfer Facility (as defined below)), as promptly as practicable following the expiration, termination or withdrawal of the Offer.

        The Purchaser reserves the right to transfer or assign to one or more of the Purchaser's affiliates, in whole or from time to time in part, the right to purchase all or any portion of the Shares tendered in the Offer, but any such transfer or assignment will not relieve the Purchaser of its obligations under the Offer or prejudice the rights of tendering stockholders to receive payment for Shares validly tendered and accepted for payment pursuant to the Offer.

2.     ACCEPTANCE FOR PAYMENT AND PAYMENT.

        Upon the terms and subject to the conditions of the Offer (including, if the Offer is extended or amended, the terms and conditions of the Offer as so extended or amended), as soon as practicable after the Expiration Date the Purchaser will purchase, by accepting for payment, and will pay for, all Shares validly tendered and not withdrawn on or prior to the Expiration Date. Any determination concerning the satisfaction of the terms and conditions of the Offer shall be within the reasonable discretion of the Purchaser. See Introduction and Section 14 for more information. The Purchaser expressly reserves the right, in its sole discretion but subject to the applicable rules of the Commission, to delay acceptance for payment of, and thereby delay payment for, Shares if any of the conditions discussed in the Introduction has not been satisfied or upon the occurrence of any of the other events specified in Section 14.

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        In all cases, payment for Shares purchased pursuant to the Offer will be made only after timely receipt by the Depositary of:

        (1)   the share certificates representing such Shares or timely confirmation (a "Book-Entry Confirmation") of the book-entry transfer of such Shares (if such procedure is available), into the Depositary's account at The Depository Trust Company (the "Book-Entry Transfer Facility"), pursuant to the procedures set forth in Section 3;

        (2)   the Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, with any required signature guarantees, or an Agent's Message (as defined below) in connection with a book-entry transfer; and

        (3)   any other documents required by the Letter of Transmittal.

        The term "Agent's Message" means a message, transmitted by the Book-Entry Transfer Facility to, and received by, the Depositary and forming a part of a Book-Entry Confirmation, which states that the Book-Entry Transfer Facility has received an express acknowledgment from the participant in the Book-Entry Transfer Facility tendering the Shares which are the subject of such Book-Entry Confirmation, that such participant has received and agrees to be bound by the terms of the Letter of Transmittal and that the Purchaser may enforce such agreement against such participant.

        For purposes of the Offer, the Purchaser will be deemed to have accepted for payment, and thereby purchased, Shares validly tendered and not withdrawn as, if and when the Purchaser gives oral or written notice to the Depositary of the Purchaser's acceptance of such Shares for payment pursuant to the Offer. In all cases, upon the terms and subject to the conditions of the Offer, payment for Shares purchased pursuant to the Offer will be made by deposit of the purchase price therefor with the Depositary, which will act as agent for tendering stockholders for the purpose of receiving payment from the Purchaser and transmitting payment to validly tendering stockholders. Upon the deposit of funds with the Depositary for the purpose of making payments to tendering stockholders, the Purchaser's obligation to make such payment shall be satisfied and tendering stockholders must thereafter look solely to the Depositary for payment of amounts owed to them by reason of the acceptance for payment of Shares pursuant to the Offer. UNDER NO CIRCUMSTANCES WILL INTEREST ON THE PURCHASE PRICE FOR SHARES BE PAID BY THE PURCHASER REGARDLESS OF ANY EXTENSION OF THE OFFER OR BY REASON OF ANY DELAY IN MAKING SUCH PAYMENT. The Purchaser will pay any stock transfer taxes incident to the transfer to it of validly tendered Shares, except as otherwise provided in Instruction 7 of the Letter of Transmittal, as well as any charges and expenses of the Depositary and the Information Agent.

        Consistent with federal law, shares properly tendered and not properly withdrawn by the Trustee of the Company's Employee Stock Ownership Plan (the "ESOP") on behalf of the participants in the ESOP may not be accepted for purchase depending on the market price of the Company's Common Stock on the date Shares are accepted and paid for under this Offer to Purchase. On such date, the Offer Price, $42.00 per Share, must be equal to or greater than the market price of the Company's Shares on the New York Stock Exchange, Inc. ("NYSE") in order for the Purchaser to purchase Shares properly tendered and not properly withdrawn by the Trustee of the ESOP. If the Offer Price is less than the market price, no Shares tendered by the Trustee on behalf of the participants in the ESOP may be accepted and purchased by the Purchaser. If applicable, those certificates for unpurchased shares will be returned promptly after the expiration of the Offer and without expense to the Trustee.

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3.     PROCEDURES FOR ACCEPTING THE OFFER AND TENDERING SHARES.

        Valid Tender of Shares.    Except as set forth below, for Shares to be validly tendered pursuant to the Offer, either

        (1)   on or prior to the Expiration Date, (a) share certificates representing tendered Shares must be received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase, or such Shares must be tendered pursuant to the book-entry transfer procedures set forth below and a Book-Entry Confirmation must be received by the Depositary, (b) the Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, together with any required signature guarantees, or an Agent's Message in connection with a book-entry transfer of Shares, must be received by the Depositary at one of such addresses and (c) any other documents required by the Letter of Transmittal must be received by the Depositary at one of such addresses, or

        (2)   the guaranteed delivery procedures set forth below must be followed.

        THE METHOD OF DELIVERY OF SHARES, THE LETTER OF TRANSMITTAL AND ALL OTHER REQUIRED DOCUMENTS, INCLUDING DELIVERY THROUGH THE BOOK-ENTRY TRANSFER FACILITY, IS AT THE ELECTION AND SOLE RISK OF THE TENDERING STOCKHOLDER, AND THE DELIVERY WILL BE DEEMED MADE ONLY WHEN ACTUALLY RECEIVED BY THE DEPOSITARY. IF DELIVERY IS BY MAIL, REGISTERED MAIL WITH RETURN RECEIPT REQUESTED, PROPERLY INSURED, IS RECOMMENDED. IN ALL CASES, SUFFICIENT TIME SHOULD BE ALLOWED TO ENSURE TIMELY DELIVERY.

        Company Employee Stock Ownership Plan.    In order for Shares to be tendered from the ESOP, stockholders must complete the Trustee Direction Form to tender some or all of the Shares allocated to their account in accordance with the form's instructions and the separate letter to the participants in the ESOP and return it to the Trustee of the ESOP by the deadline. All documents furnished to stockholders generally in connection with the Offer will be made available to stockholders who intend to tender from the ESOP. Such stockholders may not use the Letter of Transmittal to direct the tender of Shares held under the ESOP, but instead, must use the Trustee Direction Form included with the separate instruction letter. If such stockholders also hold Shares outside of the ESOP, then they must use the Letter of Transmittal to tender Shares held outside of the ESOP and must complete the Trustee Direction Form for Shares held under the ESOP. The Trustee Direction Form must be received by the Trustee no later than three business days prior to the Expiration Date, or no Shares allocated to their account will be tendered. Consistent with federal law, Shares tendered by the Trustee on behalf of the participants in the ESOP may not be accepted and purchased by the Purchaser if the tender offer price is less than the market price of the Company's stock on the NYSE on the date Shares are accepted and paid for under this tender offer. If the tender offer price is greater than or equal to the market price, then the tendered Shares will be eligible to be accepted and purchased by the Purchaser subject to the terms and conditions in this Offer to Purchase.

        Book-Entry Transfer.    The Depositary will make a request to establish accounts with respect to the Shares at the Book-Entry Transfer Facility for purposes of the Offer within two business days after the date of this Offer to Purchase. Any financial institution that is a participant with the Book-Entry Transfer Facility may make book-entry delivery of Shares by causing the Book-Entry Transfer Facility to transfer such Shares into the Depositary's account at the Book-Entry Transfer Facility in accordance with the Book-Entry Transfer Facility's procedures. Although delivery of Shares may be effected through book-entry transfer into the Depositary's account at the Book-Entry Transfer Facility, the Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, with any required signature guarantees, or an Agent's Message, and any other required documents must, in any case, be transmitted to and received by the Depositary at one of its addresses set forth on the back cover of this

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Offer to Purchase on or prior to the Expiration Date, or the guaranteed delivery procedures set forth below must be complied with.

        REQUIRED DOCUMENTS MUST BE TRANSMITTED TO AND RECEIVED BY THE DEPOSITARY AT ONE OF ITS ADDRESSES SET FORTH ON THE BACK COVER PAGE OF THIS OFFER TO PURCHASE. DELIVERY OF DOCUMENTS TO THE BOOK-ENTRY TRANSFER FACILITY IN ACCORDANCE WITH THE BOOK-ENTRY TRANSFER FACILITY'S PROCEDURES DOES NOT CONSTITUTE DELIVERY TO THE DEPOSITARY.

        Signature Guarantees.    No signature guarantee is required on the Letter of Transmittal if:

        (1)   the Letter of Transmittal is signed by the registered holder(s) (which term, for purposes of this Section, includes any participant in the Book-Entry Transfer Facility's system whose name appears on a security position listing as the owner of the Shares) of Shares tendered therewith and such registered holder has not completed either the box entitled "Special Delivery Instructions" or the box entitled "Special Payment Instructions" on the Letter of Transmittal, or

        (2)   such Shares are tendered for the account of a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a participant in the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program or the Stock Exchange Medallion Program (each, an "Eligible Institution" and, collectively, "Eligible Institutions").

In all other cases, all signatures on Letters of Transmittal must be guaranteed by an Eligible Institution. See Instructions 1 and 6 to the Letter of Transmittal for more information. If the share certificates representing the Shares are registered in the name of a person other than the signer of the Letter of Transmittal, or if payment is to be made, or share certificates not tendered or not accepted for payment are to be returned, to a person other than the registered holder of the certificates surrendered, then the tendered share certificates representing the Shares must be endorsed or accompanied by appropriate stock powers, in either case signed exactly as the name or names of the registered holders or owners appear on the certificates, with the signatures on the certificates or stock powers guaranteed as aforesaid. See Instructions 1 and 6 to the Letter of Transmittal for more information.

        If the share certificates representing the Shares are forwarded separately to the Depositary, such delivery must be accompanied by a Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, together with any required signature guarantees.

        Guaranteed Delivery.    If a stockholder desires to tender Shares under the Offer and such stockholder's share certificates are not immediately available or the procedures for book-entry transfer cannot be completed on a timely basis or time will not permit all required documents to reach the Depositary on or prior to the Expiration Date, such stockholder's tender may be effected if all the following conditions are met:

        (1)   such tender is made by or through an Eligible Institution;

        (2)   a properly completed and duly executed Notice of Guaranteed Delivery, substantially in the form provided by the Purchaser, is received by the Depositary, as provided below, on or prior to the Expiration Date; and

        (3)   within three NYSE trading days after the date of execution of such Notice of Guaranteed Delivery (a) share certificates representing tendered Shares are received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase, or such Shares are tendered pursuant to the book-entry transfer procedures and a Book-Entry Confirmation is received by the Depositary, (b) the Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, together with any required signature guarantees, or an Agent's Message in connection with a book-entry transfer of Shares, is received by the Depositary at one of such addresses and

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(c) any other documents required by the Letter of Transmittal are received by the Depositary at one of such addresses.

The Notice of Guaranteed Delivery may be delivered by hand to the Depositary, by facsimile transmission, or mailed to the Depositary and must include a guarantee by an Eligible Institution in the form set forth in such Notice of Guaranteed Delivery.

        Notwithstanding any other provision hereof, payment for Shares accepted for payment pursuant to the Offer will in all cases be made only after timely receipt by the Depositary of:

        (1)   share certificates representing tendered Shares or a Book-Entry Confirmation with respect to all tendered Shares, and

        (2)   a Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, together with any required signature guarantees, or an Agent's Message in connection with a book-entry transfer of Shares and any other documents required by the Letter of Transmittal.

Accordingly, payment might not be made to all tendering stockholders at the same time, and will depend upon when share certificates representing, or Book-Entry Confirmations of, such Shares are received into the Depositary's account at the Book-Entry Transfer Facility.

Backup U.S. Federal Income Tax Withholding

        See the discussion under the heading "Backup U.S. Federal Income Tax Withholding" in Section 5.

        Appointment as Proxy.    By executing a Letter of Transmittal as set forth above, a tendering stockholder irrevocably appoints designees of the Purchaser as such stockholder's attorneys-in-fact and proxies, in the manner set forth in the Letter of Transmittal, each with full power of substitution, to the full extent of such stockholder's rights with respect to (a) the Shares tendered by such stockholder and accepted for payment by the Purchaser and (b) any and all non-cash dividends, distributions, rights or other securities issued or issuable on or after the date of this Offer to Purchase in respect of such tendered and accepted Shares. All such proxies shall be considered coupled with an interest in the tendered Shares. This appointment will be effective if, when and only to the extent that the Purchaser accepts such Shares for payment pursuant to the Offer. Upon such acceptance for payment, all prior proxies given by such stockholder with respect to such Shares and other securities will, without further action, be revoked, and no subsequent proxies may be given nor any subsequent written consents executed (and, if given or executed, will not be deemed effective). The designees of the Purchaser will, with respect to the Shares and other securities for which the appointment is effective, be empowered to exercise all voting and other rights of such stockholder as they, in their sole discretion, may deem proper at any annual, special, adjourned or postponed meeting of the Company's stockholders, and the Purchaser reserves the right to require that in order for Shares or other securities to be deemed validly tendered, immediately upon the Purchaser's acceptance for payment of such Shares, the Purchaser must be able to exercise full voting rights with respect to such Shares. See Section 14 for more information.

        The foregoing proxies are effective only upon acceptance for payment of Shares pursuant to the Offer. The Offer does not constitute a solicitation of proxies, absent a purchase of Shares, for any meeting of the Company's stockholders, which will be made only pursuant to separate proxy solicitation materials complying with the Exchange Act. See the Introduction, Section 14 and Section 17 for more information.

        Distribution of Rights.    Stockholders will be required to tender one Right for each Share tendered to effect a valid tender of such Share. Absent action by the Company Board, the Distribution Date will occur prior to the Expiration Date. Unless and until the Distribution Date under the Company's Shareholder Rights Plan occurs, the Rights are represented by and transferred automatically with the

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Shares. Accordingly, if the Distribution Date does not occur before the Expiration Date, a tender of Shares will constitute a tender of the associated Rights. If the Distribution Date has occurred, certificates representing a number of Rights equal to the number of Shares being tendered must be delivered to the Depositary in order for such Shares to be validly tendered. If the Distribution Date has occurred, a tender of Shares without Rights constitutes an agreement by the tendering stockholder to deliver certificates representing a number of Rights equal to the number of Shares tendered pursuant to the Offer to the Depositary within three NYSE trading days after the date such Rights certificates are distributed. The Purchaser reserves the right to require that it receive such certificates before accepting Shares for payment. If the Distribution Date has occurred, unless the Rights are redeemed before the Expiration Date, stockholders who sell their Rights separately from their Shares and do not otherwise acquire Rights may not be able to satisfy the requirements of the Offer for the tender of Shares. The Purchaser will not pay any additional consideration for the Rights tendered in this Offer. See Introduction and Section 11 for more information.

        Determination of Validity.    All questions as to the form of documents and validity, eligibility (including time of receipt) and acceptance for payment of any tender of Shares will be determined by the Purchaser, in its sole discretion, whose determination will be binding on all parties. The Purchaser reserves the absolute right to reject any or all tenders determined by it not to be in proper form or the acceptance of or payment for which may, in the opinion of the Purchaser's counsel, be unlawful. The Purchaser also reserves the absolute right to waive any defect or irregularity in any tender of Shares of any particular stockholder whether or not similar defects or irregularities are waived in the case of other stockholders without any effect on the rights of such other stockholders.

        The Purchaser's interpretation of the terms and conditions of the Offer (including the Letter of Transmittal and the instructions thereto) will be binding on all parties. No tender of Shares will be deemed to have been validly made until all defects and irregularities with respect to such tender have been cured or waived. None of the Purchaser or any of its affiliates or assigns, if any, the Depositary, the Information Agent or any other person will be under any duty to give any notification of any defects or irregularities in tenders or incur any liability for failure to give any such notification.

        Other Requirements.    The Purchaser's acceptance for payment of Shares tendered pursuant to any of the procedures described above will constitute a binding agreement between the tendering stockholder and the Purchaser upon the terms and subject to the conditions of the Offer.

4.     WITHDRAWAL RIGHTS.

        Except as otherwise provided in this Section 4, tenders of Shares under the Offer are irrevocable. Shares tendered under the Offer may be withdrawn at any time on or before the Expiration Date and, unless theretofore accepted for payment as provided herein, may also be withdrawn at any time after March 19, 2007 (or such later date as may apply if the Offer is extended). If the Purchaser extends the Offer, is delayed in its acceptance for payment of Shares or is unable to purchase Shares validly tendered under the Offer for any reason, then, without prejudice to the Purchaser's rights under the Offer, the Depositary may nevertheless, on behalf of the Purchaser, retain tendered Shares, and such Shares may not be withdrawn except to the extent that tendering stockholders are entitled to withdrawal rights described in this Section 4. Any such delay will be accompanied by an extension of the Offer to the extent required by law.

        For a withdrawal to be effective, a notice of withdrawal must be timely received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase. Any such notice of withdrawal must specify the name of the person who tendered the Shares to be withdrawn, the number of Shares to be withdrawn and the name of the registered holder of the Shares to be withdrawn, if different from the name of the person who tendered the Shares. If share certificates evidencing Shares to be withdrawn have been delivered or otherwise identified to the Depositary, then, prior to the

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physical release of such certificates, the serial numbers shown on such certificates must be submitted to the Depositary and, unless such Shares have been tendered by an Eligible Institution, the signatures on the notice of withdrawal must be guaranteed by an Eligible Institution. If Shares have been delivered pursuant to the book-entry transfer procedures as set forth in Section 3, any notice of withdrawal must also specify the name and number of the account at the Book-Entry Transfer Facility to be credited with the withdrawn Shares and otherwise comply with the Book-Entry Transfer Facility's procedures.

        Withdrawals of Shares may not be rescinded. Any Shares properly withdrawn will be deemed not validly tendered for purposes of the Offer, but may be retendered at any subsequent time prior to the expiration of the Offer by following any of the procedures described in Section 3.

        All questions as to the form and validity (including time of receipt) of notices of withdrawal will be determined by the Purchaser, in its sole discretion, whose determination will be binding on all parties. None of the Purchaser or any of its affiliates or assigns, if any, the Dealer Manager, the Depositary, the Information Agent or any other person will be under any duty to give any notification of any defects or irregularities in any notice of withdrawal or incur any liability for failure to give any such notification.

        The Purchaser does not currently intend to provide a Subsequent Offering Period following the Offer. In the event that the Purchaser subsequently elects to provide a Subsequent Offering Period, no withdrawal rights will apply to Shares tendered during such Subsequent Offering Period or to Shares tendered in the Offer and accepted for payment.

        Participants in the ESOP who wish to withdraw their Shares must submit a new Trustee Direction Form indicating the withdrawal. However, the new Trustee Direction Form will only be effective if it is received by the Trustee of the ESOP by 12:00 Midnight, New York City time, Friday, February 9, 2007, three business days before the expiration of the Offer on February 14, 2007. Upon timely receipt of the new Trustee Direction Form, the old instructions will be deemed canceled. If such participants wish to later re-tender their Shares under the ESOP, then another, new Trustee Direction Form must be received by the Trustee by 12:00 Midnight, New York City time, three business days before the expiration of the Offer. While a participant may change its instructions as frequently as such participant desires pursuant to the procedure in this section, any changes to the participant's instructions must be received by the Trustee of the ESOP by 12:00 Midnight, New York City time, three business days before the Expiration Date in order to be effective.

5.     CERTAIN MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE OFFER AND THE PROPOSED MERGER.

        The following is a general discussion of certain material U.S. federal income tax consequences of the Offer and the Proposed Merger. This discussion is limited to stockholders who hold their Shares as capital assets for U.S. federal income tax purposes (the "Stockholders"). This discussion considers neither the specific facts and circumstances that may be relevant to a particular Stockholder nor any U.S. state and local or non-U.S. tax consequences of the Offer or the Proposed Merger. This discussion does not address the U.S. federal income tax consequences to a Stockholder that, for U.S. federal income tax purposes, is a non-resident alien individual, a foreign corporation, a foreign partnership, or a foreign trust or estate. Moreover, this discussion does not address special situations, such as the following:

•

tax consequences to Stockholders who may be subject to special tax treatment, such as tax-exempt entities, dealers in securities or currencies, banks, other financial institutions or "financial services entities," insurance companies, regulated investment companies, traders in securities that elect to use a mark-to-market method of accounting for their securities holdings, certain expatriates or former long-term residents of the United States or corporations that accumulate earnings to avoid U.S. federal income tax;

22

•

tax consequences to persons holding Shares as part of a hedging, integrated, constructive sale or conversion transaction or a straddle or other risk reduction transaction; and



•

tax consequences to partnerships (or other entities treated as partnerships for U.S. federal income tax purposes) or to persons who hold Shares through a partnership or similar pass-through entity.

        If a partnership or other entity treated as a partnership for U.S. federal income tax purposes holds Shares, the U.S. federal income tax treatment of a partner will generally depend on the status of the partner and the activities of the partnership. Such partners are urged to consult their tax advisors. This discussion is based upon current provisions of the Internal Revenue Code of 1986, as amended (the "Code"), existing and proposed regulations thereunder and current administrative rulings and court decisions, all as in effect on the date hereof. All of the foregoing are subject to change, possibly on a retroactive basis, and any such change could affect the continuing validity of this discussion.

        STOCKHOLDERS OF THE COMPANY SHOULD CONSULT THEIR OWN TAX ADVISORS REGARDING THE SPECIFIC TAX CONSEQUENCES TO THEM OF THE OFFER AND THE PROPOSED MERGER, INCLUDING THE APPLICABILITY AND EFFECT OF U.S. FEDERAL, STATE, LOCAL AND FOREIGN INCOME AND OTHER TAX LAWS IN THEIR PARTICULAR CIRCUMSTANCES.

In General.

        The receipt of cash pursuant to the Offer or the Proposed Merger will be a taxable transaction for U.S. federal income tax purposes and, as a result, a Stockholder will recognize gain or loss equal to the difference between the amount of cash received in connection with the Offer or the Proposed Merger and the aggregate adjusted tax basis in the Shares tendered by such stockholder and purchased pursuant to the Offer or converted into cash in the Proposed Merger, as the case may be. Gain or loss will be calculated separately for each block of Shares tendered and purchased pursuant to the Offer or converted into cash in the Proposed Merger, as the case may be. Gain or loss recognized by such stockholder will be a capital gain or loss, which will be long-term capital gain or loss if such stockholder's holding period for the Shares exceeds one year. The use of capital losses for U.S. federal income tax purposes is limited.

Backup U.S. Federal Income Tax Withholding.

        Under U.S. federal income tax laws, payments made in connection with the Offer and the Proposed Merger may be subject to "backup withholding" at a rate of 28% unless a stockholder holding Shares:

•

timely provides a correct taxpayer identification number (which, for an individual stockholder, is the stockholder's social security number) and any other required information, or



•

is a corporation or comes within certain other exempt categories and, when required, demonstrates this fact, and otherwise complies with applicable requirements of the backup withholding rules.

A stockholder that does not provide a correct taxpayer identification number may be subject to penalties imposed by the Internal Revenue Service.

        To prevent backup withholding on payments made in connection with the Offer or the Proposed Merger, each stockholder must timely provide the Depositary with his or her correct taxpayer identification number and certify under penalties of perjury that he or she is not subject to backup U.S. federal income tax withholding by completing the Substitute IRS Form W-9 included in the Letter of Transmittal. Stockholders of the Company should consult their own tax advisors as to their qualification

23

for exemption from withholding and the procedure for obtaining the exemption. See Instruction 9 and the section entitled "Important Tax Information" of the Letter of Transmittal for more information. Backup withholding is not an additional tax. Any amounts withheld from a stockholder under the backup withholding rules described above will be allowed a refund or a credit against such stockholder's U.S. federal income tax liability, provided the required information is furnished to the IRS on a timely basis.

Company Employee Stock Purchase Plan

        The exchange of Shares for cash by the Trustee of the ESOP for participants in the ESOP will not be a taxable transaction for federal income tax purposes for either the ESOP or for the participants. A subsequent distribution in cash from the ESOP to the participants will be taxable in full as ordinary income to the participants.

6.     PRICE RANGE OF THE SHARES.

        The Shares are listed and traded principally on the NYSE under the symbol "ELK." The following table sets forth, for the periods indicated, the reported high and low closing prices for the Shares on the NYSE as reported by Bloomberg, L.P.:

		High		Low
2004-2005:
	First Quarter	$	28.00	$	20.25
	Second Quarter		34.79		25.96
	Third Quarter		40.64		31.75
	Fourth Quarter		38.20		26.35
2005-2006:
	First Quarter		36.83		28.39
	Second Quarter		35.99		30.41
	Third Quarter		36.88		32.67
	Fourth Quarter		34.56		26.67
2006-2007:
	First Quarter		29.27		23.47
	Second Quarter		41.53		25.06
	Third Quarter (through January 17, 2007)		41.44		39.50

        On November 3, 2006, the last full trading day prior to BMCA's filing of its Schedule 13D and the Company's announcement of its sale process, the closing price per Share as reported on the NYSE was $25.18 per share. On January 17, 2007, the last full trading day prior to the commencement of the Offer, the closing price per share on the NYSE was $41.21 per share. According to the Company Form 10-K, as of July 31, 2006, the number of holders of record of the Shares was 880.

Stockholders are urged to obtain a current market quotation for the Shares.

7.     EFFECT OF THE OFFER ON THE MARKET FOR THE SHARES; NYSE LISTING; MARGIN REGULATIONS; EXCHANGE ACT REGISTRATION.

        NYSE Listing.    The purchase of Shares under the Offer will reduce the number of Shares that might otherwise trade publicly and could reduce the number of holders of Shares, which could adversely affect the liquidity and market value of the remaining Shares held by the public. According to the NYSE's published guidelines, the NYSE would consider delisting the Shares if, among other things, (1) the total number of holders of Shares fell below 400, (2) the total number of holders of Shares fell below 1,200 and the average monthly trading volume over the most recent 12 months was less than

24

100,000 Shares, (3) the number of publicly held Shares (exclusive of holdings of officers, directors and their families and other concentrated holdings of 10% or more) fell below 600,000, (4) the Company's average global market capitalization over a consecutive 30-trading-day period was less than $25 million, or (5) the average closing price per share was less than $1.00 over a consecutive 30-trading-day period. According to the Schedule 14D-9, as of January 5, 2007, there were 20,624,468 Shares outstanding. According to the Company Form 10-K, as of July 31, 2006, the outstanding Shares were held by 880 holders of record. If, as result of the purchase of Shares in the Offer or otherwise, the Shares no longer meet the requirements of the NYSE for continued listing and the listing of the Shares is discontinued, the market for the Shares could be adversely affected.

        If the NYSE were to delist the Shares, it is possible that the Shares would continue to trade on another securities exchange or in the over-the-counter market and that price or other quotations would be reported by such exchange or through the Nasdaq Stock Market or other sources. The extent of the public market therefor and the availability of such quotations would depend, however, upon such factors as the number of stockholders and /or the aggregate market value of such securities remaining at such time, the interest in maintaining a market in the Shares on the part of securities firms, the possible termination of registration under the Exchange Act as described below and other factors. The Purchaser cannot predict whether the reduction in the number of Shares that might otherwise trade publicly would have an adverse or beneficial effect on the market price for or marketability of the Shares or whether it would cause future market prices to be greater or less than the Offer Price.

        Margin Regulations.    The Shares are currently "margin securities" under the regulations of the Board of Governors of the Federal Reserve System (the "Federal Reserve Board"), which has the effect, among other things, of allowing brokers to extend credit on the collateral of the Shares. Depending upon factors similar to those described above regarding listing and market quotations, following the Offer, it is possible that the Shares may no longer constitute "margin securities" for purposes of the margin regulations of the Federal Reserve Board, in which event the Shares could no longer be used as collateral for loans made by brokers.

        Exchange Act Registration.    The Shares are currently registered under the Exchange Act. Such registration may be terminated upon application of the Company to the Commission if the Shares are not listed on a national securities exchange or quoted on the Nasdaq Stock Market and there are fewer than 300 record holders of the Shares. The termination of registration of the Shares under the Exchange Act would substantially reduce the information required to be furnished by the Company to holders of Shares and to the Commission and would make certain provisions of the Exchange Act, such as the short-swing profit recovery provisions of Section 16(b) of the Exchange Act, the requirement to furnish a proxy statement in connection with stockholders' meetings pursuant to Section 14(a) of the Exchange Act, and the requirements of Rule 13e-3 under the Exchange Act with respect to "going-private" transactions, no longer applicable to the Company. See Section 11 for more information. In addition, "affiliates" of the Company and persons holding "restricted securities" of the Company may be deprived of the ability to dispose of such securities under Rule 144 under the Securities Act of 1933, as amended (the "Securities Act"). If registration of the Shares under the Exchange Act were terminated, the Shares would no longer be "margin securities" or be eligible for listing on the NYSE.

8.     CERTAIN INFORMATION CONCERNING THE COMPANY.

        The information concerning the Company contained in this Offer to Purchase has been taken from or based upon publicly available documents and records on file with the Commission and other public sources and is qualified in its entirety by reference thereto. None of the Purchaser, its affiliates, the Dealer Manager, the Information Agent or the Depositary has received any representations from the Company regarding any information contained in such documents or records or the completeness or accuracy of any such information, and none of the Purchaser, its affiliates, the Dealer Manager, the Information Agent or the Depositary generally has access to a means of obtaining independently verified

25

information, or themselves verifying any such information, concerning the Company. None of the Purchaser, its affiliates, the Dealer Manager, the Information Agent or the Depositary can take responsibility for the accuracy or completeness of the information contained in such documents and records, or for any failure by the Company to disclose events which may have occurred or may affect the significance or accuracy of any such information but which are unknown to the Purchaser, its affiliates, the Dealer Manager, the Information Agent or the Depositary, except to the extent required by law.

        According to the Form 10-K, the Company was incorporated in the State of Delaware in 1965. The principal executive office of the Company is located at 14911 Quorum Drive, Suite 600, Dallas, Texas 75254-1491 and its telephone number is (972) 851-0500. The Company is a manufacturer of premium roofing products and composite building products, including laminated fiberglass asphalt shingles. The Company's primary focus centers on three building products platforms: Premium Roofing Products, Composite Building Products and Specialty Fabric Technologies. It maintains one additional segment, Surface Finishes, which includes hard chrome and other finishes designed to extend the life of steel machinery components operating in abrasive environments.

        The Company is subject to the informational filing requirements of the Exchange Act and, in accordance therewith, is required to file periodic reports, proxy statements and other information with the Commission relating to its business, financial condition and other matters. Such reports, proxy statements and other information can be inspected and copied at the public reference facilities maintained by the Commission at 100 F Street, N.E., Washington, D.C. 20549. Information regarding the public reference facilities may be obtained from the Commission by telephoning 1-800-SEC-0330. The Company's filings are also available to the public on the Commission's Internet site (http://www.sec.gov). Copies of such materials also may be obtained by mail from the Public Reference Section of the Commission at 100 F Street, N.E., Washington, D.C. 20549 at prescribed rates. Copies of many of the items filed with the Commission and other information concerning the Company are available for inspection at the offices of the NYSE located at 20 Broad Street, New York, New York 10005.

9.     CERTAIN INFORMATION CONCERNING THE PURCHASER AND ITS AFFILIATES.

        The Purchaser is a newly incorporated Delaware corporation organized in connection with the Offer and the Proposed Merger and has not carried on any activities other than in connection with the Offer and the Proposed Merger. The Purchaser was incorporated under the laws of Delaware in 2006. The principal offices of the Purchaser are located at 1361 Alps Road, Wayne, New Jersey 07470 and its telephone number is (973) 628-3000. The Purchaser is a wholly-owned subsidiary of the Parent.

        The Parent is a newly incorporated Delaware corporation organized in connection with the Offer and the Proposed Merger and has not carried on any activities other than in connection with the Offer and the Proposed Merger. The Parent was incorporated under the laws of Delaware in 2006. The principal offices of the Parent are located at 1361 Alps Road, Wayne, New Jersey 07470 and its telephone number is (973) 628-3000. The Parent is a wholly-owned subsidiary of BMCA.

        The Purchaser and the Parent are affiliated with HIA, a Connecticut limited partnership, Samuel J. Heyman, a citizen of the United States of America ("Mr. Heyman"), BMCA, a Delaware Corporation, BMCA Holdings Corporation, a Delaware corporation ("BHC"), G-I Holdings Inc., a Delaware corporation ("G-I Holdings"), G Holdings Inc., a Delaware corporation ("G Holdings") and Heyman Holdings Associates Limited Partnership, a Connecticut limited partnership ("Heyman Holdings"). Mr. Heyman is the sole general partner of each of HIA and Heyman Holdings. Mr. Heyman beneficially owns (as defined in Rule 13d-3 under the Securities Exchange Act of 1934, as amended ("Rule 13d-3")) approximately 99% of G Holdings and controls G Holdings through his ownership of Heyman Holdings. G Holdings controls G-I Holdings. G-I Holdings controls BHC. BHC controls BMCA. BMCA controls the Parent. The Parent controls the Purchaser. HIA, Mr. Heyman, BMCA, BHC, G-I Holdings, G Holdings and Heyman Holdings are sometimes hereinafter collectively referred to as the "Purchaser Affiliates."

26

        HIA and Heyman Holdings each have their principal place of business at 333 Post Road West, Westport, Connecticut 06880. BMCA, G-I Holdings and G Holdings each have their principal place of business at 1361 Alps Road, Wayne, New Jersey 07470. BHC has its principal place of business at 300 Delaware Avenue, Suite 303, Wilmington, Delaware 19801. Mr. Heyman has his principal place of business at 667 Madison Avenue, 12th Floor, New York, New York 10021.

        HIA is an investment partnership. Heyman Holdings is an investment partnership whose business consists primarily of owning a control interest in G Holdings. The business of G Holdings consists primarily of owning 100% of the capital stock of G-I Holdings. The business of G-I Holdings consists primarily of owning 100% of the capital stock of BHC. The business of BHC consists primarily of owning the capital stock of BMCA. BMCA is a leading national manufacturer and marketer of a broad line of asphalt and polymer based roofing products and accessories for the residential and commercial roofing markets. BMCA also manufactures specialty building products and accessories for the professional and do-it-yourself remodeling and residential construction industries. Mr. Heyman is the general partner of HIA, the general partner of Heyman Holdings, a director and the Chief Executive Officer, President and Secretary of G Holdings and a director and the Chief Executive Officer, President and Secretary of G-I Holdings.

        Neither the Parent nor the Purchaser is subject to the informational filing requirements of the Exchange Act, and, accordingly, they do not file reports or other information with the Commission relating to their business, financial condition or other matters.

        BMCA is subject to the informational filing requirements of the Exchange Act and, in accordance therewith, is required to file periodic reports with the Commission relating to its public indebtedness. Such reports can be inspected and copied at the public reference facilities maintained by the Commission at 100 F Street, N.E., Washington, D.C. 20549. Information regarding the public reference facilities may be obtained from the Commission by telephoning 1-800-SEC-0330. BMCA's filings are also available to the public on the Commission's Internet site (http://www.sec.gov). Copies of such materials also may be obtained by mail from the Public Reference Section of the Commission at 100 F Street, N.E., Washington, D.C. 20549 at prescribed rates.

        The name, business address and telephone number, citizenship, present principal occupation and employment history of each of the directors, executive officers and control persons of the Purchaser, the Parent and the Purchaser Affiliates are set forth in Schedule I hereto. None of the Purchaser, the Parent, the Purchaser Affiliates, or, to the best of their knowledge, any of the persons listed in Schedule I hereto has, during the past five years, been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors). None of the Purchaser, the Parent, the Purchaser Affiliates, or, to the best of their knowledge, any of the persons listed in Schedule I hereto has, during the past five years, been a party to any judicial or administrative proceeding (except for matters that were dismissed without sanction or settlement) that resulted in a judgment, decree or final order enjoining the person from future violations of, or prohibiting activities subject to, federal or state securities laws, or a finding of any violation of federal or state securities laws.

        The Purchaser's affiliate, HIA, owns 2,123,799 Shares and the Purchaser owns one Share, collectively representing approximately 10% of the number of outstanding shares of Common Stock. This percentage has been calculated based upon a total of 20,624,468 Shares issued and outstanding as reported by the Company in the Schedule 14D-9. The aggregate amount of funds used by HIA to purchase the 2,123,800 Shares owned by it (including the one Share subsequently transferred to BMCA and then contributed to the Purchaser) was approximately $55 million, including commission. The funds used to purchase the Shares were obtained by HIA from the working capital of HIA, funds of HIA from capital contributions of its partners and borrowings pursuant to standard margin arrangements. On December 19, 2006, HIA transferred one Share to BMCA. On January 17, 2007, BMCA contributed one Share to the Parent, who subsequently contributed one Share to the Purchaser. A

27

description of all other transactions involving the Purchaser and its affiliates in Shares is attached as Schedule II of this Offer to Purchase.

        In a letter dated August 28, 2006 from Mr. Heyman, the general partner of HIA, to Robert Tafaro, the President and Chief Executive Officer of BMCA (the "August Letter"), Mr. Heyman agreed, upon BMCA's request, to sell any Shares of the Company owned by Mr. Heyman and his affiliates to BMCA at cost.

        In addition to the Shares held by HIA, David Harrison, a director of BMCA, beneficially owns 500 Shares. Neither BMCA nor HIA has the power to vote, direct the voting of, dispose of or direct the disposition of, the shares held by Mr. Harrison.

        Except as set forth elsewhere in this Offer to Purchase (including Schedule I and Schedule II hereto), (i) none of the Purchaser, the Parent or, to the knowledge of the Purchaser, any of the persons listed in Schedule I hereto, beneficially owns or has a right to acquire any Shares or any other equity securities of the Company, and (ii) none of the Purchaser, the Parent or the Purchaser Affiliates, to the knowledge of the Purchaser, the Parent or the Purchaser Affiliates, any of the persons or entities referred to in clause (i) above or any of their executive officers, directors or subsidiaries, has effected any transaction in the Shares or any other equity securities of the Company during the past 60 days.

        Except as set forth elsewhere in this Offer to Purchase (including Schedule I hereto), (i) none of the Purchaser, the Parent or, to the knowledge of the Purchaser, any of the persons listed on Schedule I hereto, has any contract, arrangement, understanding or relationship with any other person with respect to any securities of the Company and (ii) during the two years prior to the date of this Offer to Purchase, there have been no transactions that would require reporting under the rules and regulations of the Commission between the Purchaser, the Parent or any of the Purchaser Affiliates or, to the knowledge of the Purchaser, the Parent or the Purchaser Affiliates, any of the persons listed in Schedule I hereto, on the one hand, and the Company or any of its executive officers, directors and/or affiliates, on the other hand.

        Except as set forth elsewhere in this Offer to Purchase, during the two years prior to the date of this Offer to Purchase, there have been no contracts, negotiations or transactions between the Purchaser, the Parent or any of the Purchaser Affiliates or, to the knowledge of the Purchaser, the Parent or the Purchaser Affiliates, any of the persons listed in Schedule I hereto, on the one hand, and the Company or the Purchaser Affiliates, on the other hand, concerning a merger, consolidation or acquisition, a tender offer or other acquisition of securities, an election of directors or a sale or other transfer of a material amount of assets.

10.   BACKGROUND OF THE OFFER; CONTACTS WITH THE COMPANY.

        As of the close of business on November 1, 2006, HIA, an affiliate of BMCA, had acquired 2,123,800 Shares, representing 10.36% of the outstanding Shares. HIA acquired the Shares to facilitate a possible business combination between the Company and BMCA.

        On November 2, 2006, Robert B. Tafaro, the Chief Executive Officer and President of BMCA, called Thomas D. Karol, Chairman of the Board and Chief Executive Officer of the Company, to relay that an affiliate of BMCA had acquired more than 10% of the outstanding Shares of the Company. Mr. Tafaro proposed that they meet in person to discuss a possible business combination between the Company and BMCA.

        On November 5, 2006, members of management of the Company and BMCA and their respective advisors had a call to discuss BMCA's interest in a business combination. During this call the Company confirmed that there was an on-going sale process that it expected to complete by the end of November 2006. BMCA expressed surprise that it had not been invited into the sale process at inception given the fact that BMCA believed that it would have had to be considered the Company's

28

most logical strategic merger partner. Although the Company did not explain why BMCA had not been contacted, the Company did say BMCA would now be invited to participate in the sale process and, subject to the execution of a standard confidentiality agreement, BMCA would be given access to the confidential diligence materials that had been provided to other bidders.

        On November 6, 2006, BMCA submitted the following letter to Mr. Karol and the Company Board further indicating its interest in pursuing a business combination with the Company at an all cash price to be negotiated. BMCA filed the letter as an exhibit to its Schedule 13D.

November 6, 2006

Mr. Thomas D. Karol
Chairman of the Board and Chief Executive Officer ElkCorp
14911 Quorum Drive, Suite 600
Dallas, Texas 75254-1491

Dear Tom:

        As we advised you last week and again on our Sunday conference call, we have a strong interest in pursuing a business combination with Elk at an all cash price to be negotiated. We believe that a combination of our two companies provides Elk stockholders with the opportunity to realize full value for their shares because of the unique synergies that exist between our two businesses which are an excellent fit for each other. For this same reason, the combination will provide significant benefits to Elk customers and employees.

        As you know, in addition to the extremely difficult operating environment we in the roofing industry now confront—resulting from unprecedented asphalt costs, margin erosion, and excess inventories—the industry faces significant long-term challenges as well. It is now readily apparent that, in the last few years, aberrational demand from weather-related events temporarily obscured the impact of higher costs and slowing industry growth, especially in the maturing market for laminated shingles. In our view, consolidation is the only logical response to these conditions.

        We have always held Elk and its employees in the highest regard, having known each other as competitors, suppliers, and friends. In recent months, we have carefully studied this combination and believe that Elk and BMCA are uniquely complementary. The limited overlap among customers and distribution channels, as well as the geographic fit of our companies' respective facilities, offer an opportunity to enhance the combined company's competitive position by achieving economies of scale and improving our ability to respond to customer needs to a degree that would not be available to either company on a stand-alone basis or with any other partner.

        As a combined company, we would lead the industry as the lowest-cost roofing manufacturer in the country, able to deliver product quickly and efficiently to customers in every section of the country. Our customers would also benefit from access to the most comprehensive product offering in roofing, the industry's oldest and most developed contractor programs, and two of the industry's most trusted and respected brand names. Finally, bringing together our companies' world-class employees, who have driven exceptional innovation and strong historical growth at both our companies, will ensure that the combined company competes effectively in the marketplace whatever challenges we face going forward.

        We have invested a significant amount of time and money in the evaluation of a transaction between our companies. Since our companies have known each other for many years, we are quite familiar with your business, as we know that you are with ours. With your cooperation, after conducting reasonable confirmatory due diligence, we expect to be in a position to promptly provide an appropriate offer to you and your stockholders. As discussed on our conference call, we are willing, of course, to execute a customary confidentiality agreement. In addition, you should

29

know that as a result of our discussions with lenders, we are confident that satisfactory financing for the transaction is readily available and our offer will not be subject to a financing contingency.

        Finally, you should be aware that we and our advisers have thoroughly considered the antitrust implications of this transaction, and we are highly confident that there will not be any antitrust impediments to completion. In that regard, we are filing today a Hart-Scott-Rodino notification with the Federal Trade Commission and the Antitrust Division of the United States Department of Justice.

        We are sorry that the New York Marathon prevented our meeting in person yesterday, but we appreciated the opportunity to present our proposal by teleconference instead. I look forward to our continued discussions.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

P.S. I am enclosing a copy the 13D filing reflecting our Elk stake.

Enclosure

cc: The ElkCorp Board of Directors

        Shortly after the conference call on November 5, 2006, BMCA was provided with the Company's confidentiality and standstill agreement. The agreement contained restrictions which BMCA believed would have unreasonably tied its hands and prevented it from communicating an offer to the Company Board or to stockholders in the event that the Company terminated its process prematurely or preferred a bidder who could not deliver as much value as BMCA. BMCA believed these provisions to be onerous and unreasonable in light of its significant investment in the Company. The advisors of BMCA attempted to reach a compromise with the Company's advisors, but the Company's advisors stated that the Company had no flexibility.

        On November 13, 2006, members of management of the Company and BMCA met in Dallas, Texas. At the meeting, BMCA stated that it would not enter into the restrictive standstill agreement that was proposed by the Company. In addition, BMCA stated that while it preferred to receive confidential information, it was the Company's choice as to whether BMCA would bid with or without access to such confidential information. Following the meeting, on November 15, 2006, without the benefit of confidential information, BMCA submitted the following letter to the Company Board proposing a merger that would provide $35.00 per share cash consideration for all outstanding Shares, pursuant to which BMCA made clear that it hoped to be able to increase its offer price if given access to the confidential information provided to other bidders. BMCA filed the letter as an exhibit to its amended Schedule 13D.

November 15, 2006

Mr. Thomas D. Karol
Chairman of the Board and CEO
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

Dear Tom:

        It was good meeting with you, your colleagues, and advisors on Monday evening in Dallas, and I appreciate your accommodating the meeting on such short notice.

30

        In response to your invitation to put our best foot forward, we want you to know that BMCA is prepared, based upon publicly available information, to enter into a merger agreement with Elk providing cash consideration for all outstanding Elk common shares of $35 per share. The merger would not be conditioned upon financing but would be subject to Hart-Scott-Rodino approval, the rescission of Elk's poison pill, and other customary conditions.

        As we have pointed out, we believe that BMCA is the highest and best merger partner for Elk given BMCA's leading position in the industry and the unique synergies which exist between our businesses. Because of our position in the industry, we are well aware of the significant benefits of a merger between our Companies as well as the difficult current operating environment and significant long term challenges we both now confront.

        Again, we are proceeding based upon publicly available information, and should Elk decide to share confidential information with BMCA, we would hope to see evidence of additional value that would enable BMCA to increase its price.

        BMCA's proposal provides a compelling opportunity for Elk stockholders to realize significant value for their shares in an all cash transaction with no significant regulatory hurdles anticipated. It should be noted that the proposed price represents an approximate 40% premium over Elk's closing price on November 3rd ($25.18 per share), the trading day immediately preceding BMCA's filing of its 13D and Elk's announcement of its sale process, and a meaningful premium over Elk's current trading price.

        As we provided you and your colleagues and advisers with a "heads up" at our Monday night meeting and again earlier today, we are proceeding along this line only after Elk and its advisors have chosen to exclude us from the on-going sale process because of their insistence that we enter into what we regard as an onerous standstill agreement. The proposed agreement would unreasonably tie BMCA's hands and prevent us under any circumstances from making an offer directly to stockholders.

        By way of background, in our teleconference on Sunday, November 5th, you agreed that Elk would include BMCA as part of its ongoing sale process and provide us, subject to a confidentiality agreement, with due diligence similar to that which Elk had already provided other bidders. You indicated further that the process had been underway for sometime and that you were expecting to complete it by the end of November. Parenthetically, we still do not understand why we were not invited into the sale process at inception given the fact that BMCA would have had to be considered Elk's most logical strategic merger partner.

        Shortly after the November 5th conference, your advisors provided BMCA with confidentiality and standstill agreements, the latter containing unreasonable demands concerning our Elk ownership position and BMCA's future course of action. By way of example, under Elk's proposed agreement, it could terminate the process and discussions with our Company for any reason at any time while preventing us, for a period of two years, from submitting our offer directly to Elk stockholders.

        In addition, under the Elk proposal, as your advisors have acknowledged, the Company reserved the right to change the rules of the process at any time, notwithstanding the fact that this could have the effect of creating an unlevel playing field—and all this while BMCA would be obligated to stand still. We had similar objections to other provisions which would operate to prevent us from submitting an offer to stockholders under other circumstances as well. Although we continued to seek throughout the past week a reasonable compromise, your advisors reiterated that your Company had little or no flexibility.

        At our meeting in Dallas on Monday night, we stated that we could simply not see our way clear, as a substantial Elk stockholder, to enter into the standstill agreement that your advisors had

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proffered. We further went on to indicate that it was Elk's choice as to whether BMCA would proceed as part of your process or outside the process while BMCA stated that it was its strong preference to participate in the process believing that course to be in the interests of both companies. Based upon Elk's decision, you and your advisors have left us no alternative but to proceed in this fashion.

        We reiterate our interest in a friendly transaction and remain open to any further discussion that you and your advisors wish to pursue.

All the best.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

cc: Elk Board of Directors

        On November 16, 2006, the Company issued a press release in response to the above November 15, 2006 letter sent by BMCA, claiming falsely that BMCA indicated no willingness to compromise on the terms of the confidentiality and standstill agreement. Over the next several weeks, the Company, BMCA and their respective advisors from time to time attempted to negotiate the terms of the confidentiality and standstill agreement. The Company continued to insist on what BMCA believed was an overly restrictive standstill and showed little or no flexibility in negotiating the restrictive standstill provisions.

        On December 11, 2006, BMCA submitted the following letter to Mr. Karol and the Company Board reporting that it had obtained financing commitments from Deutsche Bank and Bear Stearns and that the waiting period under the Hart-Scott-Rodino Antitrust Improvement Act had expired. BMCA reiterated its interest in moving forward to promptly negotiate a definitive merger agreement and sought the Company's guidance on how to proceed. The letter was filed as an exhibit to its amended Schedule 13D.

December 11, 2006

Mr. Thomas D. Karol
Chairman of the Board and CEO
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

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        Dear Tom:

        We wanted to update you and the Elk Board on the status of BMCA's merger proposal to provide cash consideration for all outstanding Elk common shares of $35 per share. We can now report that we have obtained financing commitments from Deutsche Bank and Bear Stearns sufficient to fund the full price of the transaction. In addition, as you know, we announced last Thursday that the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act had expired.

        As we have previously pointed out, we believe that BMCA is the highest and best merger partner for Elk given BMCA's leading position in the industry and the unique synergies which exist between our businesses. We believe our $35 per share proposal provides a compelling opportunity for Elk stockholders to realize significant value for their shares in an all cash transaction. The price is approximately 40% above Elk's closing price on November 3rd ($25.18 per share), the trading day immediately preceding BMCA's filing of its 13D and Elk's announcement of its sale process.

        By way of recap, while we appear to be in substantial agreement on the terms of a confidentiality agreement, as we previously indicated in our letter of November 15^th, we could not accept the standstill you proposed. The proposed standstill would have unreasonably tied our hands and prevented us from communicating an offer to the Board or stockholders in the event that you terminated your process prematurely or preferred a bidder who could not deliver as much value to Elk stockholders as we can.

        We trust that you and the Elk Board fully appreciate the seriousness of our proposal and that you will see fit to move forward with us to promptly negotiate a definitive merger agreement. We continue to believe that an expeditious process is in the best interests of Elk, its stockholders, customers and employees. BMCA stands ready and willing to complete this transaction, and we await your guidance as to how you wish us to proceed.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

cc: Elk Board of Directors

        On December 11, 2006, in addition to sending the above letter, Mr. Tafaro contacted Mr. Karol to reiterate the seriousness of BMCA's proposal and to again seek guidance as to how the Company wished BMCA to proceed with its proposal. Mr. Karol offered no guidance and instead told Mr. Tafaro that the Company was considering BMCA's proposal and that BMCA would have the Company's response "in a matter of days." BMCA never heard back from Mr. Karol.

        On Tuesday, December 12, 2006, representatives of BMCA also contacted UBS to seek guidance as to how the Company wished BMCA to proceed with its proposal. UBS informed BMCA that the Company had a board meeting scheduled for the next day (December 13, 2006) and that BMCA's proposal was one of the items on the agenda at that meeting. UBS said it would be in a position to provide guidance immediately following that meeting and that BMCA should expect a call from UBS after the meeting. Having not heard from UBS by Friday, December 15^th, BMCA placed a second call to UBS which was not returned.

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        On December 17, 2006, Mr. Tafaro sent the following letter to Mr. Karol and the Company Board announcing BMCA's intention to commence an offer to purchase all of the outstanding Shares at $35.00 per Share:

December 17, 2006

Mr. Thomas D. Karol
Chairman of the Board and CEO
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

Dear Tom:

        We are today announcing that we will be commencing a tender offer for all outstanding Elk common shares at $35 per share. As you know, we have already received antitrust clearance and this offer is not conditional on financing.

        Tom, BMCA has been both open and direct in all its dealings with you, your colleagues, and outside advisors. Notwithstanding, Elk has refused to enter into discussions with us regarding our merger proposal or provide confidential information as it has with other bidders. Most recently, on Tuesday, December 12^th, our representatives contacted your financial advisors, UBS, seeking guidance on how best to proceed. UBS informed us that BMCA's merger proposal was scheduled to be considered at an Elk Board meeting on December 13^th and that they would be in a position to provide us with guidance in a call immediately after the meeting. Instead, we have heard nothing from your advisors, and they have since "gone off the air."

        You should know that, in light of the above, you have given us no choice but to take our offer directly to shareholders. Please be assured that we continue to stand ready to negotiate a definitive merger agreement directly with Elk, if it so chooses, and we believe this to be in the best interests of Elk, its shareholders and employees.

All the best.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

cc: Elk Board of Directors

        At approximately 4 a.m., New York time, on December 18, 2006, the Company's counsel sent an email to BMCA seeking to persuade BMCA to defer making its tender offer. Later that morning, without notice to BMCA and without affording it an opportunity to increase its offer, the Company announced that it had entered into a definitive agreement with affiliates of The Carlyle Group to acquire the Company in a leveraged buyout involving management participation at $38.00 per Share in cash.

        During the evening of December 18, 2006, BMCA submitted the following letter to the Company Board announcing its intention to commence a tender offer providing $40.00 per Share cash consideration for all outstanding Shares instead of the $35.00 previously announced:

December 18, 2006

Board of Directors
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

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Ladies and Gentlemen:

        This is to advise you that BMCA is raising its tender offer price from $35 to $40 per share cash consideration for all Elk shares.

        We were surprised and disappointed by your announcement today that you have agreed to a leveraged buyout for Elk involving management participation, as this was done without once contacting us regarding our proposal to buy Elk or providing an opportunity for BMCA to bid. As you know, BMCA advised Elk more than four weeks ago, on November 15th, that BMCA was in a position to consider increasing its $35 per share price. Finally, instead of encouraging BMCA to maximize the value of its offer, to add insult to injury, your advisors attempted, in a 3:49 AM email on Monday morning, to persuade us to defer making the tender offer to your shareholders that we had informed you about on Sunday night. How could these actions possibly be in the interests of Elk shareholders?

        While you have not communicated the details of your leveraged buyout, we trust that you have not agreed to anything that would prevent us from competing economically and in effect preclude a higher offer for your shareholders. Finally, our offer is obviously superior to the Elk leveraged buyout in both price and the fact that BMCA's offer is a tender offer, not subject to regulatory clearance, and, barring any undue delay on the part of Elk, should close in January 2007.

        Please advise us how you wish to proceed.

All the best.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

On December 20, 2006, BMCA commenced a tender offer (the "Prior Tender Offer").

        Pursuant to the Company's expressed interest in a negotiated merger, on December 24, 2006, counsel to BMCA delivered a draft merger agreement to the Company's counsel, which was superior to the Carlyle merger agreement in both timing and price and, BMCA believes, was at least as strong as the Carlyle agreement with regard to every other provision. BMCA reiterated its request for access to reasonable due diligence information that was, at the very least, substantially the same as the due diligence provided to other bidders. Finally, after almost two months of negotiations, BMCA and the Company entered into a confidentiality and standstill agreement on December 29, 2006, in which the Company agreed to provide such due diligence. Even with this agreement, the due diligence process was frustratingly slow and continued to be managed by the Company's Chief Executive Officer who will be a participant in the competing Carlyle transaction.

        On January 5, 2007, BMCA sent the following letter to the Special Committee of the Board of Directors of the Company expressing frustration over the slow access to diligence and clarifying its expectations with respect to the tender offer process and negotiation of a merger agreement:

January 5, 2007

Special Committee of the Board of Directors of ElkCorp
c/o Mark Gordon, Esq.
Wachtell, Lipton, Rosen & Katz
51 West 52nd Street
New York, NY 10019

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Ladies and Gentlemen:

        On Friday, December 29, 2006, our Companies entered into confidentiality and standstill agreements, under which BMCA has been promised access to reasonable diligence in order to create a level playing field and enable it to maximize value to Elk shareholders.

        Notwithstanding the agreement, progress in terms of the due diligence process has proven, at least until late yesterday afternoon, frustratingly slow. By way of background, after signing the confidentiality agreement last Friday, BMCA's management team offered to travel to Dallas and work with Elk over the holiday weekend. Elk declined to do so, finally scheduling a conference call at noon on Tuesday. On this call, the only Elk management representative was Tom Karol, while other members of Elk management who presumably would have been in a position to respond to a number of our due diligence inquiries were for some reason excluded.

        Moreover, on the same conference call, raising questions as to whether we were entitled to the most basic information, Tom declined to respond to approximately 25 separate, entirely appropriate inquiries. By way of just one example, we were unable to obtain, or even receive a commitment to furnish, information concerning the Company's financial performance in October, November, and December 2006. Although Tom promised to reconsider his position at a subsequent time, and has since agreed to provide the requested information, it has been painfully slow in coming. In this connection, while BMCA's due diligence team was scheduled to meet with Tom and three other Elk executives this morning in Dallas, this meeting had to be postponed because information we had been promised by Elk had not been made available as of the time our people had to leave for the airport yesterday afternoon. Since that time, we have confirmed a rescheduled meeting for Saturday morning and are at last in the process of receiving meaningful due diligence information.

        Given the background of Elk's entire process, which we understand began 4-5 months ago, together with our recent experience, I think you can well understand our concern. As you know, although BMCA is Elk's most logical merger partner, the process had proceeded for months with a number of management buyout firms without so much as an invitation to BMCA to participate. Then when we surfaced with our proposal, which included a clear statement that we were willing to consider paying more, we were, for all intents and purposes, shut out of the process because we were unwilling, not surprisingly, to sign an extremely onerous standstill agreement whose principal points we were told were not subject to negotiation. And then without so much as calling BMCA to provide it with an opportunity to increase its merger price proposal, Elk proceeded to enter into an agreement with Carlyle, at a price now shown to be inferior, obligating Elk to pay a $29 million breakup fee.

        On another issue, Tom and your advisors requested this past Tuesday information about the merger process. Since then, we and your advisors have had a number of conversations regarding the process and our currently pending tender offer. While we do not believe that there should be any ambiguity, perhaps in an excess of caution, we again summarize the state of play as follows:

        1.    Tender Offer.    BMCA has pending a tender offer for all shares of ElkCorp common stock at $40 per share, in cash, not subject to a diligence or financing condition. We are ready, willing and able to close the tender offer subject to the satisfaction of the conditions to the offer. Satisfaction of the principal conditions are within ElkCorp's control. You need only lift the Rights Plan, and waive the application of Delaware 203 and Article Thirteen of your Certificate of Incorporation. As disclosed in the offer, we would then pursue a second step merger at the same price per share as the tender offer; or

        2.    Negotiated Merger Agreement.    Alternatively, we understand the interest Elk has expressed in managing any further rounds of this bidding contest and moving toward a negotiated merger agreement. To that end, we have delivered a draft agreement that is superior to the Carlyle

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agreement in both timing and price, and at least as strong as the Carlyle agreement with regard to every other contractual provision. We have received your advisors' comments on that agreement and our financing letters. In response, we have redrafted the merger agreement accepting all reasonable proposals and the financing letters which now address the three specific issues they raised as concerns. These documents will be returned to your advisors today.

        In order to put BMCA on a level playing field in this bidding contest, we agreed Friday night that Elk would provide access to reasonable due diligence but in no event less than what was provided to Carlyle. We encouraged Elk to do this because we believe that only by being on a level playing field with Carlyle can we deliver a binding merger agreement with terms acceptable to you and participate most effectively in any further rounds of the current bidding contest. Whatever the faults of the process to date, it should be readily apparent that a fair process and a level playing field will deliver the most value to Elk's shareholders.

        Given the pendency of our tender offer and our delivery of draft documents for a negotiated merger agreement, we do not understand how the Special Committee can maintain its current recommendation of the Carlyle offer. Our $40 offer, on substantially the same terms as your current Merger Agreement, is a "Superior Proposal" that we think compels your Board to consider a Change of Recommendation. We therefore urge you to provide the notice required by Section 5.3(d) of your current Merger Agreement to CGEA Holdings, Inc.

        As I think is plainly apparent, we are seriously committed to concluding the Elk-BMCA merger, and we trust that your Committee will do the right thing so that we will both be in a position to close this transaction at the earliest possible time. In the meantime, if you have any questions the Committee should like to discuss, Sam Heyman and I will be pleased to meet with the Special Committee at its earliest convenience.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

cc:

Mr. Thomas D. Karol, CEO
Mr. Lee Lebrun, UBS

        On January 8, 2007, the Company filed a Schedule 14D-9 with the Commission, in which it recommended that its stockholders reject the Prior Tender Offer and made numerous inaccurate statements with respect to such offer. On January 9, 2007, BMCA sent the following letter to the Special Committee of the Company Board responding to those inaccuracies and reiterating its commitment to work towards a negotiated transaction.

January 9, 2007

Special Committee of the Board of Directors of ElkCorp
c/o Mark Gordon, Esq.
Wachtell, Lipton Rosen & Katz
51 West 52nd Street
New York, NY 10019

Ladies and Gentlemen:

        We have reviewed the 14D9 Elk filed late yesterday afternoon and hasten to reply. While we appreciate the Committee's commitment to continue the due diligence process with a view toward entering into a mutually satisfactory merger agreement, we were surprised by the multitude of inaccuracies and the adversarial tone and emphasis of the document.

37

        By way of just one example, the 14D9 suggests that BMCA's pending tender offer is conditioned on due diligence. In point of fact, nothing could be further from the truth, as its express terms make clear and our January 5^th letter confirms. The offer does include quite naturally conditions customary in tender offers made without confidential information, such as its material adverse change provision. There should be nothing surprising about an offer made without the assistance of due diligence—which the Committee had denied us at the time of the filing of the offer—where an offeror seeks to protect itself in the event of a material adverse change. All that being said, BMCA continues to be willing to proceed on the terms of its pending tender offer.

        When the Committee, however, stated its interest in substantially narrowing the tender offer conditions, BMCA and the Committee agreed to negotiate a two-step tender and merger agreement on terms equal or superior to Elk's Carlyle agreement, and to include new terms more appropriate for an agreement made with confidential information. To this end, we entered into confidentiality and standstill agreements to provide BMCA with access to due diligence so as to be able to reach a merger agreement with the Committee with substantially narrower conditions. With regard to the material adverse change provision mentioned above, for example, BMCA agreed that it would substantially narrow the material adverse change provision after you had taken us through, and gotten us comfortable with, the Company's recent operating performance and plan for 2007.

        Notwithstanding Elk's agreement to provide reasonable due diligence—and I would acknowledge that the pace has accelerated markedly in the last several days—it continues to be a challenging process. With all due respect, we believe this results from a process that has been flawed from the very beginning wherein access to information, negotiation of the agreements, and other aspects of the process are being managed by a Chief Executive, who is for all intents and purposes a competing bidder, and an investment banker, who at least in the early stages of the process was working with senior management, before the involvement of the Special Committee, to assist it, among other things, in interesting a management buyout partner. Not surprisingly, this process has already exposed the Elk Board and Members of the Special Committee to several serious lawsuits.

        Despite our recent progress on the due diligence front, you should know that any number of our reasonable diligence requests are still being filibustered by management and its advisors. By way of several recent examples, we are currently being denied access to any information concerning Elk's December performance, information concerning Elk's material contracts and obligations, and the Company's most recent outlook and plan for 2007. These requests are well within the scope of any normal diligence and should not be the subject of negotiation.

        Although we have made plain at the outset that BMCA's offer is not conditioned upon financing, we nonetheless furnished the Committee with copies of our financing commitments to which the Company's 14D9 now takes issue. By way of background, when your advisors questioned the form of our financing commitments, claiming that they were not as precise or strong as Carlyle's, we asked the Committee to furnish us with the forms of commitment provided by Carlyle so that we could work with our underwriters to refine the commitments accordingly. Unfortunately, BMCA has still not received an answer to this request made about two weeks ago and restated as recently as this past Sunday afternoon.

        By way of further background concerning BMCA's financing commitments, approximately two weeks ago the Company's advisors provided comments on our financing commitments, citing three concerns. We immediately conferred with BMCA's underwriters, redrafted the commitments to address the three issues, and the revised financing commitments were delivered to the Committee last Friday. Then after having had our original financing commitments for three weeks, ELK forwarded on Saturday night (just in time to make it into the 14D9!), an extensive list of new

38

"issues" involving primarily mechanical form-over-substance considerations which had not been raised before—obviously not leaving time to respond before the filing of the Committee's 14D9. Among the issues raised by the Company's advisors were many that had already been resolved or were clearly inappropriate.

        Moreover, there are other material inaccuracies in your 14D9, too many to enumerate here. By way of just one example, you cite the need for BMCA note holder consents as a condition of the tender even though we announced on Friday and informed Elk's advisors on Sunday that the consents have already been received. More generally, it would be constructive if BMCA were given a meaningful chance to respond to Elk's advisors' concerns, both real and illusory, before they become the basis of the Committee's decisions.

        We are confident that our proposal is superior, we are absolutely committed to concluding this transaction and maximizing value for Elk shareholders, and we stand ready to work with you towards a negotiated transaction. Finally, we renew our earlier suggestion to meet directly with the Special Committee and its advisors so as to correct any needless misunderstanding and assure that the process from here moves forward in the most constructive fashion.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

cc:

Mr. Thomas D. Karol, CEO
Mr. Lee Lebrun, UBS

        On Friday January 12, 2007, after substantial discussions, representatives of BMCA communicated to the Company's counsel that BMCA would be sending a revised draft merger agreement and revised financing commitment letters reflecting compromises resulting from the considerable negotiations that had occurred between the Company's and BMCA's advisors. The revised financing commitments, disclosed in connection with this Offer, are now in the form the Company requested.

        During the holiday weekend of January 13, 2007, representatives of the Company and BMCA and their advisors had various discussions regarding due diligence and the contents of BMCA's revised proposal. On Tuesday, January 16, 2007, without contacting BMCA regarding its revised proposal, the Company attempted to prematurely terminate its auction by announcing that it had amended its merger agreement with affiliates of The Carlyle Group such that those affiliates would now pay $40.50 per Share and would launch a tender offer on January 18, 2007. In addition, on January 16, 2007, the Company terminated BMCA's access to due diligence. Counsel to BMCA informed the Company's counsel on that same day that BMCA was considering whether it would increase its offer, and expressed BMCA's interest in completing the already commenced diligence with that goal in mind.

        BMCA received no response to that request and decided, consistent with the two-step transaction structure in the merger agreement that BMCA has been negotiating with the Company, to have the Purchaser make this Offer directly to the Company's stockholders. On January 18, 2006, BMCA terminated the Prior Tender Offer and the Purchaser commenced the Offer.

        In connection with the filing of the Offer, BMCA sent the following letter to the Company's Special Committee in which it urged that the due diligence process be resumed so as to enable the Purchaser to release the various conditions of the Offer, which it will do upon satisfactory completion of due diligence.

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January 18, 2007

Special Committee of the Board of Directors of ElkCorp
c/o Mark Gordon, Esq.
Wachtell Lipton Rosen & Katz
51 West 52nd Street
New York, NY 10019

Ladies and Gentlemen:

        This is to advise you that BMCA, through its acquisition subsidiary, has raised its tender offer price this morning from $40 to $42 per share cash consideration for all Elk shares, effectively superseding BMCA's previous tender offer. In addition, J.P. Morgan Securities has joined our bank consortium with Deutsche Bank and Bear Stearns, and we have financing commitments, in the form you requested, sufficient to fund the full price of the transaction.

        We were again disappointed by your announcement on Tuesday that you have entered into a revised merger transaction with Carlyle, with Elk's CEO to be a partner in the buyout group, without notice to BMCA affording it the opportunity to increase its bid. As you know, we were, until the Tuesday announcement, making substantial progress toward a mutually acceptable merger agreement, had received revised financing commitments in the form you requested, and performed due diligence. In the latter connection, as a result of the hard work of my BMCA colleagues and their Elk counterparts, working sometimes around the clock over the past two weeks, we have managed to finish a substantial portion of the same due diligence that Carlyle had been working on for some months.

        We believe that the action taken by Elk on Tuesday represents an attempt to prematurely terminate the auction process. At the same time, Elk unilaterally terminated the due diligence process. The fact that we are in a competitive situation only underscores our need for the balance of the due diligence information so that we can participate on a level playing field and have the opportunity to maximize value for Elk shareholders.

        Based upon BMCA's increased tender offer price, our offer is clearly superior to Carlyle's revised offer, and we urge that the due diligence process be resumed so as to enable BMCA to eliminate certain tender offer conditions, as BMCA and Elk had already agreed subject to satisfactory completion of due diligence. We are highly committed to this transaction and stand ready to conclude a mutually agreeable negotiated transaction at the earliest possible time.

Sincerely,

/s/ Robert B. Tafaro
Robert B. Tafaro
President and Chief Executive Officer

cc:

Mr. Thomas D. Karol, CEO
Mr. Lee Lebrun, UBS

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        Transactions With the Company.    During the past several years, there have been purchases and sales of granule products in the ordinary course of business between each of ISP Technologies Inc. and ISP Minerals Inc., which are related companies and affiliates of BMCA, on the one hand, and the Company on the other hand. Aggregate sales of granule products by ISP Technologies Inc. and ISP Minerals Inc. to the Company were approximately $2 million for the 2006 fiscal year through October 1, 2006, approximately $80,000 for the fiscal year ended December 31, 2005, and approximately $350,000 for the fiscal year ended December 31, 2004.

        During the past several years, there have been purchases and sales of glass mat products, Hip & Ridge products and other products in the ordinary course of business between BMCA and its subsidiaries, on the one hand, and the Company on the other hand. Aggregate sales of glass mat products by the Purchaser and its subsidiaries to the Company were approximately $2 million for the 2006 fiscal year through October 1, 2006, approximately $565,000 for the fiscal year ended December 31, 2005, and approximately $10,000 for the fiscal year ended December 31, 2004. Aggregate sales of Hip & Ridge products by BMCA and its subsidiaries to the Company were approximately $785,000 for the 2006 fiscal year through October 1, 2006 and approximately $92,000 for the fiscal year ended December 31, 2005. Aggregate purchases of Hip & Ridge products by BMCA and its subsidiaries from the Company were approximately $2.2 million for the 2006 fiscal year through October 1, 2006, approximately $2 million for the fiscal year ended December 31, 2005, approximately $1.7 million for the fiscal year ended December 31, 2004, and approximately $1.3 million for the fiscal year ended December 31, 2003.

        Transactions Involving Company Shares.    On December 19, 2006, HIA transferred one Share to BMCA. On January 17, 2007, BMCA contributed one Share to the Parent, who subsequently contributed one Share to the Purchaser. A description of all other transactions involving Purchaser and its affiliates in Company Shares is attached as Schedule II of this Offer to Purchase.

11.   PURPOSE OF THE OFFER; PLANS FOR THE COMPANY; STATE ANTI-TAKEOVER LAWS.

        General.    The purpose of the Offer is for the Purchaser to acquire control of, and ultimately the entire equity interest in, the Company. If the Offer is consummated, the Parent intends, as soon as practicable following the consummation of the Offer, to have the Company consummate the Proposed Merger pursuant to which each then outstanding Share (other than Shares beneficially owned by BMCA) would be converted into the right to receive an amount in cash per Share equal to the highest price per Share paid by the Purchaser pursuant to the Offer, without interest.

        BMCA previously made an offer to purchase the Shares for $40.00 per Share directly to the Company's stockholders. The Company recommended that its stockholders reject that offer and proceeded to amend and restate its merger agreement with affiliates of The Carlyle Group. In light of these events, BMCA decided, consistent with the two-step transaction structure in the merger agreement that BMCA has been negotiating with the Company, to have the Purchaser make this Offer directly to the Company's stockholders. However, there are substantial conditions to consummation of the Offer, among them the Section 203 Condition, the Rights Condition and the Article Thirteenth Condition. If the Company Board opposes the Offer, certain provisions of the DGCL and of the Company's Charter and By-Laws would affect the Purchaser's ability to obtain control of the Company and to effect the Proposed Merger. Therefore, there can be no assurance that the Purchaser will be able to consummate the Offer or, if the Offer is consummated, that the Purchaser will be able to effectuate the Proposed Merger, nor can there be any guarantee as to the timing of the Proposed Merger if it is consummated. See below and Section 14 for more information.

        Company Board and Stockholder Approval.    The timing and details of the consummation of the Offer and the Proposed Merger depend on a variety of factors and legal requirements, the number of Shares (if any) acquired by the Purchaser pursuant to the Offer, and most importantly, actions of the

41

Company Board. In general, under the DGCL, the approval of both the stockholders and the board of directors of a corporation is required to effect a merger of that corporation with or into another corporation. The Proposed Merger can only be effected with the approval of the Company Board and the affirmative vote of the holders of at least a majority of the outstanding shares. If the Minimum Tender Condition, the Section 203 Condition, the Rights Condition, the Article Thirteenth Condition and the other conditions to the Offer discussed in the Introduction and Section 14 are satisfied, the Purchaser will own Shares representing at least a majority of the outstanding Shares after consummation of the Offer, and will have the voting power necessary to assure approval of the Proposed Merger by the Company's stockholders and, after voting in elections for directors at the Company's annual meeting of stockholders for at least two consecutive years, to have elected a majority of the members of the Company Board. Although the Purchaser will seek to have the Company consummate the Proposed Merger as soon as practicable after consummation of the Offer, because the Proposed Merger must be approved by the Company Board, the Proposed Merger could be delayed for a substantial period of time if the Company Board refuses to approve the Proposed Merger, or if a majority of the members of the Company Board refuse to resign in favor of designees of the Purchaser.

        The satisfaction of the principal conditions to the Offer, with the exception of the Minimum Tender Condition, is within the control of the Company Board. The Purchaser believes that the Company Board should take all necessary actions to facilitate consummation of the Offer and hereby requests that they do so. Unless the Company Board acts to facilitate consummation of the Offer, the Offer will not be able to proceed.

        The Purchaser currently intends to pursue the Proposed Merger following consummation of the Offer. The Purchaser, however, reserves the right not to pursue the Proposed Merger at all, to amend the terms of the Proposed Merger, or to pursue an alternative second step business combination transaction involving the Company in which the Shares not owned by BMCA or its affiliates would be converted into securities or other consideration, or exchanged for cash.

        Anti-Takeover Laws.    The Company is incorporated under the laws of the State of Delaware. In general, Section 203 of the DGCL prevents an "Interested Stockholder" (including a person who owns or has the right to acquire 15% or more of a corporation's outstanding voting stock) from engaging in a "Business Combination" (which term includes mergers and certain other actions) with a Delaware corporation for a period of three years following the date such person became an interested stockholder unless, among other things, the transaction which resulted in the stockholder becoming an interested stockholder is approved by the board of directors of such corporation prior to such date.

        A number of states have adopted laws and regulations that purport to apply to attempts to acquire corporations that are incorporated in such states, or whose business operations have substantial economic effects in such states, or which have substantial assets, security holders, employees, principal executive offices or principal places of business in such states. In Edgar v. MITE Corp., the Supreme Court of the United States (the "Supreme Court") invalidated on constitutional grounds the Illinois Business Takeover statute, which, as a matter of state securities law, made certain corporate acquisitions more difficult. However, in 1987, in CTS Corp. v. Dynamics Corp. of America, the Supreme Court held that the State of Indiana may, as a matter of corporate law and, in particular, with respect to those aspects of corporate law concerning corporate governance, constitutionally disqualify a potential acquiror from voting on the affairs of a target corporation without the prior approval of the remaining stockholders. The state law before the Supreme Court was by its terms applicable only to corporations that had a substantial number of stockholders in the state and were incorporated there.

        The Purchaser does not believe that the anti-takeover laws and regulations of any state other than the State of Delaware will by their terms apply to the Offer. The Purchaser reserves the right to challenge the applicability or validity of any state law purportedly applicable to the Offer and nothing in this Offer to Purchase or any action taken in connection with the Offer is intended as a waiver of

42

such right. If it is asserted that any state anti-takeover statute is applicable to the Offer and an appropriate court does not determine that it is inapplicable or invalid as applied to the Offer, the Purchaser might be required to file certain information with, or to receive approvals from, the relevant state authorities, and the Purchaser might be unable to accept for payment or pay for Shares tendered pursuant to the Offer or may be delayed in consummating the Offer. In any such case, the Purchaser may not be obligated to accept for payment, or pay for, any Shares tendered pursuant to the Offer.

        Appraisal Rights.    Appraisal rights are not available in the Offer. If the Proposed Merger is consummated, however, holders of Shares at the effective time of the Proposed Merger who do not vote in favor of, or consent to, the Proposed Merger will have rights under Section 262 of the DGCL to demand appraisal of their Shares. Under Section 262, stockholders who demand appraisal and comply with the applicable statutory procedures will be entitled to receive a judicial determination of the fair value of their Shares, exclusive of any element of value arising from the accomplishment or expectation of the Proposed Merger, and to receive payment of that fair value in cash, together with a fair rate of interest, if any. Any such judicial determination of the fair value of Shares could be based upon factors other than, or in addition to, the price per Share to be paid in the Proposed Merger or the market value of the Shares. The value so determined could be more or less than the price per Share to be paid in the Proposed Merger.

        The foregoing summary of Section 262 of the DGCL does not purport to be complete and is qualified in its entirety by reference to Section 262. Failure to follow the steps Section 262 requires for perfecting appraisal rights may result in the loss of those rights.

        "Going-Private" Transactions.    Rule 13e-3 under the Exchange Act is applicable to certain "going-private" transactions and may, under certain circumstances, be applicable to the Proposed Merger. The Purchaser does not believe that Rule 13e-3 will be applicable to the Proposed Merger unless the Proposed Merger is consummated more than one year after the termination of the Offer. However, in the event that the Purchaser is deemed to have acquired control of the Company pursuant to the Offer and if the Proposed Merger is consummated more than one year after the completion of the Offer, or an alternative transaction is effected whereby stockholders of the Company receive consideration less than that paid pursuant to the Offer, in either case at a time when the Shares are still registered under the Exchange Act, the Purchaser may be required to comply with Rule 13e-3 under the Exchange Act. If applicable, Rule 13e-3 would require, among other things, that certain financial information concerning the Company and certain information relating to the fairness of the Proposed Merger or alternative transaction and the consideration offered to minority stockholders in the Proposed Merger or alternative transaction be filed with the Commission and distributed to minority stockholders before the consummation of any such transaction. The purchase of a substantial number of Shares pursuant to the Offer may result in the Company's being able to terminate its Exchange Act registration. See Section 7 for more information. If such registration were terminated, Rule 13e-3 would be inapplicable to any future merger or alternative transaction.

        Short-Form Merger.    Under Section 253 of the DGCL, if a corporation owns at least 90% of the outstanding shares of each class of a subsidiary corporation, the corporation holding such stock may merge such subsidiary into itself or itself into such subsidiary, without any action or vote on the part of the board of directors or stockholders of such other corporation (a "short-form merger"). If the Purchaser acquires, pursuant to the Offer or otherwise, at least 90% of the outstanding Shares, the Purchaser will be able to effect the Proposed Merger without a vote of the Company's stockholders. In the event that the Purchaser acquires in the aggregate at least 90% of the outstanding Shares pursuant to the Offer or otherwise, then, at the election of the Purchaser, a short-form merger could be effected without any further approval of the Company Board or the stockholders of the Company.

        Shareholder Rights Plan.    The completion of the Offer is conditioned upon, among other things, the Rights issued under the Company's Shareholder Rights Plan having been amended or otherwise

43

rendered inapplicable to the Offer or having been redeemed by the Company Board, or the Purchaser being satisfied, in its reasonable judgment, that the Rights are invalid or otherwise inapplicable to the Offer and the Proposed Merger.

        The Rights Condition is significant to the Offer because if the Purchaser were to purchase Shares under the Offer and the Rights were triggered by such purchase, each Right would entitle its holder, other than the Purchaser and its affiliates or associates, to purchase, upon payment of the applicable exercise price, preferred stock of the Company or Common Stock of the Company at a discount. If after a triggering event the Company merges, consolidates or engages in a similar transaction in which the Company does not survive, each Right-holder would also have the right to buy discounted stock in the surviving entity. Any of these circumstances would result in the Purchaser suffering unacceptable dilution of its interest in the Company.

        The following summary of certain provisions of the Company's Shareholder Rights Plan relating to the Rights is based upon the Company's Current Report on Form 8-K filed with the Commission on May 29, 1998, and the Company's Shareholder Rights Plan filed therewith, and the amendment to the Company's Shareholders Rights Plan filed as an exhibit to the Company's Current Report on Form 8-K filed with the Commission on November 6, 2006. This summary is not intended to be complete, and is qualified in its entirety by reference to such filing and the full text of the Company's Shareholder Rights Plan and the related amendment thereto, each of which is attached as an exhibit to such filing.

        Under the Company's Shareholder Rights Plan, Rights were constructively distributed as a dividend at the rate of one Right for each share of Common Stock held by Company stockholders of record as of the close of business on July 8, 1998. Until the occurrence of certain triggering events, the Rights are represented by, and trade in tandem with, the Common Stock.

        Shortly after the Company was informed by BMCA that it had acquired beneficial ownership of more than 10% of the Company's Common Stock, the Company amended its Shareholder Rights Plan to decrease, from 15% to 10%, the percentage of beneficial ownership of the Company's Common Stock that triggers the separation of the Rights from the Common Stock and the exercisability thereof. As amended, the Rights separate from the Common Stock and become exercisable upon the Distribution Date, which is the earlier to occur of (i) the close of business on the tenth day after the first date of public announcement that a person or group has acquired beneficial ownership of 10% or more of the Company's Common Stock (or, for persons having beneficial ownership of 10% or more of the Shares as of November 5, 2006, the time that such person acquires beneficial ownership of additional Shares after November 5, 2006), or (ii) the close of business on the tenth day after a tender or exchange offer has been launched by any person or group unaffiliated with the Company and who, by virtue of consummating the tender or exchange offer, would acquire beneficial ownership of 10% or more of the Company's Common Stock (or, for persons having beneficial ownership of 10% or more of the Shares as of November 5, 2006, would result in such person acquiring beneficial ownership of additional Shares after November 5, 2006).

        Following the occurrence of a Distribution Date and the separation of the Rights from the Common Stock, the Company's stockholders are entitled to purchase, at a pre-determined purchase price per Right, one one-hundredth (1/100th) of a share of Series A Participating Preferred Stock for each Right. In addition, if the Purchaser becomes an "Acquiring Person," meaning that the Purchaser becomes the beneficial owner of 10% or more of the Company's Common Stock, or, since the Purchaser had beneficial ownership of 10% or more of the Shares as of November 5, 2006, the Purchaser acquires any additional Shares, the Rights would entitle the holders other than the Purchaser and its affiliates to purchase Common Stock of the Company at a 50% discount. If after a triggering event the Company merges, consolidates or engages in a similar transaction in which the Company does not survive, each holder of a Right also has the ability to purchase discounted stock in the surviving entity.

44

        The Company Board may amend or supplement the Company's Shareholder Rights Plan at any time prior to the time that any person or group becomes an Acquiring Person. The Company Board may also, at its option, redeem all of the outstanding Rights at a price of $0.01 per Right so long as no person or group has become an Acquiring Person. In connection with the Offer, unless the Company's Shareholder Rights Plan is amended or otherwise rendered inapplicable to the Offer, or the Rights have been redeemed, either of which is in the complete discretion of the Company Board, stockholders are required to tender one Right for each Share tendered in order to effect a valid tender of the Shares. If the Distribution Date does not occur before the Expiration Date, a tender of Shares in this Offer will automatically constitute a tender of the associated Rights. If the Distribution Date has occurred, the certificates representing the Rights will have to be tendered along with the certificates evidencing the Shares tendered.

        At its meeting on January 7, 2007, the Company Board took action, as permitted by the Company's Shareholder Rights Plan, to postpone the Distribution Date. Until the Distribution Date, the Rights will continue to be evidenced by the certificates for the Shares, and the Rights will be transferable only in connection with the transfer of the associated Shares.

The Company Board can satisfy the Rights Condition by amending the Company's Shareholder Rights Plan to render the Rights inapplicable to the Offer and the Proposed Merger or by acting to redeem the Rights. The Purchaser believes that that the Company Board should take such action or make such amendment and hereby requests that they do so. If the Company Board does not act to make the Company's Shareholder Rights Plan inapplicable to the Offer and Proposed Merger, the Purchaser would suffer unacceptable dilution of its interest in the Company were the Purchaser to purchase Shares under the Offer and it is likely that the Purchaser would not consummate the Offer.

        Other.    The Purchaser reserves the right to purchase, following the consummation or termination of the Offer, additional Shares in the open market, in privately negotiated transactions, in another tender offer or exchange offer or otherwise. In addition, in the event that the Purchaser decides not to pursue the Proposed Merger, the Purchaser will evaluate its other alternatives. Such alternatives could include proposing a merger on terms other than those described above, purchasing additional Shares in the open market, in privately negotiated transactions, in another tender offer or exchange offer or otherwise, or taking no further action to acquire additional Shares. Any additional purchases of Shares could be at a price greater or less than the price to be paid for Shares in the Offer and could be for cash or other consideration. Alternatively, the Purchaser or any of its affiliates may sell or otherwise dispose of any or all Shares acquired in the Offer or otherwise. Each such transaction may be effected on terms and at prices then determined by the Purchaser or the applicable affiliate, which may vary from the terms and price in the Offer.

        Future Plans for the Company in Addition to the Proposed Merger.    In connection with the Offer, the Purchaser has reviewed, and will continue to review on the basis of publicly available information, various possible business strategies that it might consider if the Purchaser acquires control of the Company. In addition, if and to the extent that the Purchaser acquires control of the Company or otherwise obtains access to the books and records of the Company, the Purchaser intends to conduct a detailed review of the Company and its assets, financial projections, corporate structure, dividend policy, capitalization, operations, properties, policies, management and personnel and consider and determine what, if any, changes would be desirable in light of the circumstances which then exist. Such strategies could include, among other things, changes in the Company's business, facility locations, assets, corporate structure, marketing strategies, capitalization, management or dividend policy.

        Except as indicated in this Offer to Purchase, the Purchaser does not have any current plans or proposals which relate to or would result in (i) any extraordinary transaction, such as a merger, reorganization or liquidation of the Company or any of its subsidiaries, (ii) any purchase, sale or transfer of a material amount of assets of the Company or any of its subsidiaries, (iii) any material

45

change in the present dividend rate or policy, or indebtedness or capitalization of the Company, (iv) any change in the current board of directors or management of the Company, (v) any other material change in the Company's corporate structure or business, (vi) any class of equity security of the Company being delisted from a national stock exchange or ceasing to be authorized to be quoted in an automated quotation system operated by a national securities association or (vii) any class of equity securities of the Company becoming eligible for termination of registration under Section 12(g)(4) of the Exchange Act.

12.   SOURCE AND AMOUNT OF FUNDS.

        The Purchaser expects that approximately $970 million would be required to consummate the Offer and the Proposed Merger and to pay related fees and expenses. The Purchaser anticipates funding of all of the purchase price and related expenses with funds to be borrowed under credit facilities (the "Credit Facilities") fully committed to by Deutsche Bank, Bear Stearns and J.P. Morgan Securities (the "Lead Arrangers"). The Credit Facilities also provide for the refinancing of certain outstanding indebtedness of BMCA and, if the Proposed Merger takes place, the outstanding indebtedness of the Company (the "Refinancing"). Funding under the Credit Facilities is conditioned on the satisfaction of conditions customary in similar transactions. As this is a fully committed financing, the Purchaser does not anticipate the need to seek alternate financing sources.

        The Credit Facilities are to be documented in definitive loan documents among BMCA, the Purchaser and, as agreed, certain other subsidiaries of BMCA, as borrowers, Deutsche Bank, Bear Stearns and J.P. Morgan Securities and other banks and financial institutions to become parties thereto as lenders, and Deutsche Bank, as administrative agent for the lenders. The Credit Facilities will consist of a $950 million seven-year amortizing term loan facility (the "Term Loan Facility"), a $600 million five-year revolving credit facility (the "Revolving Facility") and an up to $325 million one-year bridge credit facility (the "Bridge Facility"). To the extent that the Bridge Facility is not repaid within one year from the initial borrowing thereunder, the Bridge Facility will convert into a term loan maturing eight years after the initial borrowing under the Bridge Facility. The proceeds of the Credit Facilities are to be used (i) to fund the purchase price of the Shares tendered in the Offer, (ii) to repurchase or otherwise retire BMCA's notes due 2007 and 2008, (iii) to refinance other outstanding indebtedness of BMCA, (iv) if the Proposed Merger takes place, to pay for all Shares that are not purchased in the Offer as well as the refinancing of the outstanding indebtedness of the Company, (v) to pay fees and expenses incurred in connection with the Offer, the Refinancing and, to the extent necessary, the Proposed Merger and (vi) for working capital and general corporate purposes of BMCA and its subsidiaries. At or prior to the Merger, BMCA may elect to increase the commitments under the Revolving Facility by up to $100 million provided that the Term Loan Facility is reduced or prepaid by a like amount.

        All amounts owing under the Revolving Facility will be secured by a first priority perfected security interest in all receivables, inventory, platinum and rhodium, deposit accounts and other current assets of BMCA and its domestic subsidiaries and all proceeds thereof (the "Revolving Facility Collateral"). All amounts owing under the Term Loan Facility will be secured by (i) a first priority perfected security interest in substantially all of the assets and properties of BMCA and its domestic subsidiaries, other than the Revolving Facility Collateral (the "Term Facility Collateral"), and (ii) a second priority perfected security interest in the Revolving Facility Collateral. All amounts owing under the Bridge Facility will be secured by a perfected second priority security interest in the Term Loan Facility Collateral and a perfected third priority security interest in the Revolving Facility Collateral. No property or assets of the Company or any of its subsidiaries will be collateral for the Credit Facilities prior to the consummation of the Proposed Merger.

        Loans under the Term Loan Facility and the Revolving Facility will bear interest at a variable rate based upon either the prime rate or LIBOR, at the borrower's option, plus a specified margin in each

46

case. These interest rates will be recalculated periodically based on changes in the LIBOR and prime rates, if applicable, and, in the case of loans under the Revolving Facility, also based on a leverage based pricing grid.

        The Credit Facilities will contain various customary covenants, including with respect to mandatory prepayments of loans, restrictive covenants with respect to incurring additional indebtedness or guarantees, creating liens or other encumbrances and financial covenants.

        BMCA and its subsidiaries, including the Purchaser, plan to repay the loans under the Credit Facilities with funds generated by BMCA and its subsidiaries' operations, existing capital and assets.

        Funding under the Credit Facilities is conditioned on the satisfaction of conditions customary in similar transactions, including (i) satisfaction of the Minimum Tender Condition and the Rights Condition; (ii) completion of the refinancing with respect to indebtedness of BMCA and its subsidiaries (but excluding the Company and its subsidiaries); (iii) the Credit Facilities having received ratings from Standard & Poor's Rating Services and Moody's Investor's Services; and (iv) there not occurring any fact, circumstance, event, change, effect or occurrence since June 30, 2006 that has or would be reasonably likely to have a material adverse effect on the business, results of operation or financial condition of the Company and its subsidiaries, taken as a whole, but in any case, shall not include facts, circumstances, events, changes, effects or occurrences (a) generally affecting the industries in which the Company and its subsidiaries operate (including general pricing changes), or the economy or the financial or securities markets in the United States or elsewhere in the world (including any regulatory and political conditions or developments, or any outbreak or escalation of hostilities, declared or undeclared acts of war or terrorism), except to the extent any fact, circumstance, event, change, effect or occurrence that, relative to other industry participants, disproportionately impacts the assets, properties, business, results of operation or financial condition of the Company and its subsidiaries, taken as a whole, (b) resulting from the announcement of the Offer, the Credit Facilities or the Refinancing or (c) resulting from any litigation related to the proposed Offer, the Credit Facilities or the Refinancing, and provided that any failure to meet internal or published projections, forecasts or revenue or earning predictions for any period shall not, in and of itself, constitute a material adverse effect.

        THE OFFER IS NOT CONDITIONED ON THE PURCHASER OBTAINING FINANCING.

13.   DIVIDENDS AND DISTRIBUTIONS.

        If, on or after the date of this Offer to Purchase, the Company should, during the pendency of the Offer, (i) split, combine or otherwise change the Shares or its capitalization, (ii) acquire Shares or otherwise cause a reduction in the number of Shares or other securities, (iii) issue or sell additional Shares, any shares of any other class of capital stock, other voting securities or any securities convertible into or exchangeable for, or rights, warrants or options, conditional or otherwise, to acquire, any of the foregoing, or (iv) disclose that it has taken such action, then, without prejudice to the Purchaser's rights under Section 14, the Purchaser, in its sole discretion, may make such adjustments in the Offer Price and other terms of the Offer and the Proposed Merger as it deems appropriate to reflect such split, combination or other change, including, without limitation, the number or type of securities offered to be purchased.

        If, on or after the date of this Offer to Purchase, the Company declares or pays any cash dividend on the Shares or other distribution on the Shares (except for regular quarterly cash dividends on the Shares not in excess of $0.05 per share having customary and usual record dates and payment dates), or issues with respect to the Shares any additional Shares, shares of any other class of capital stock, other voting securities or any securities convertible into, or rights, warrants or options, conditional or otherwise, to acquire, any of the foregoing, payable or distributable to stockholders of record on a date prior to the transfer of the Shares purchased pursuant to the Offer to the Purchaser or its nominee or

47

transferee on the Company's stock transfer records, then, subject to the provisions of Section 14 (i) the Offer Price may, in the sole discretion of the Purchaser, be reduced by the amount of any such cash dividends or cash distributions; and (ii) the whole of any such non-cash dividend, distribution or issuance to be received by the tendering stockholders will (a) be received and held by the tendering stockholders for the account of the Purchaser and will be required to be promptly remitted and transferred by each tendering stockholder to the Depositary for the account of the Purchaser, accompanied by appropriate documentation of transfer, or (b) at the direction of the Purchaser, be exercised for the benefit of the Purchaser, in which case the proceeds of such exercise will promptly be remitted to the Purchaser. Pending such remittance and subject to applicable law, the Purchaser will be entitled to all rights and privileges as owner of any such non-cash dividend, distribution, issuance or proceeds and may withhold the entire Offer Price or deduct from the Offer Price the amount or value thereof, as determined by the Purchaser in its sole discretion.

14.   CERTAIN CONDITIONS TO THE OFFER.

        Notwithstanding any other provisions of the Offer, and in addition to (and not in limitation of) the Purchaser's rights to extend and amend the Offer at any time, in its sole discretion, the Purchaser shall not be required to accept for payment or, subject to any applicable rules and regulations of the Commission, including Rule 14e-1(c) under the Exchange Act (relating to the Purchaser's obligation to pay for or return tendered Shares promptly after termination or withdrawal of the Offer), pay for, and may delay the acceptance for payment of and accordingly the payment for, any tendered Shares, and may terminate the Offer, if, in the reasonable judgment of the Purchaser, (1) on or prior to the Expiration Date, any one or more of the Minimum Tender Condition, the Section 203 Condition, the Rights Condition or the Article Thirteenth Condition has not been satisfied, or (2) at any time on or after the date of this Offer to Purchase and before the time of payment for any such Shares (whether or not any Shares have theretofore been accepted for payment pursuant to the Offer), any of the following events shall occur or shall be determined by the Purchaser to have occurred:

        (1)   there has been or will be any action taken, or any statute, rule, regulation, legislation, interpretation, judgment, order or injunction enacted, enforced, promulgated, amended, issued or deemed applicable to the Offer, the Company, the Purchaser or any of its affiliates, by any legislative body, court, government or governmental, administrative or regulatory authority or agency, domestic or foreign that, in the reasonable judgment of the Purchaser, would be expected to, directly or indirectly:

•

make illegal or otherwise prohibit or materially delay consummation of the Offer or the Proposed Merger or seek to obtain material damages or make materially more costly the making of the Offer,



•

prohibit or materially limit the ownership or operation by the Purchaser or any of its affiliates of all or any material portion of the business or assets of the Company or any of its subsidiaries taken as a whole or compel the Purchaser or any of its affiliates to dispose of or hold separately all or any material portion of the business or assets of the Purchaser or any of its affiliates or of the Company or any of its subsidiaries taken as a whole, or seek to impose any material limitation on the ability of the Purchaser or any of its affiliates or of the Company to conduct its business or own such assets,



•

impose material limitations on the ability of the Purchaser or any of its affiliates effectively to acquire, hold or exercise full rights of ownership of the Shares, including, without limitation, the right to vote any Shares acquired or owned by the Purchaser or any of its affiliates, or to finance the purchase price of the Shares,



•

require divestiture by the Purchaser or any of its affiliates of any Shares,

48

•

result in a material adverse effect on the Purchaser, any of its affiliates or the Company or the value of the Shares,



•

result in a material diminution in the benefits expected to be derived by the Purchaser or any of its affiliates as a result of the Offer or any merger or other business combination involving the Company; or

        (2)   there has been or will be instituted or pending any action or proceeding by any governmental entity or third party seeking, or that would reasonably be expected to result in any of the consequences referred to in the clauses of paragraph (1) above; or

        (3)   the Purchaser shall become aware of any change, circumstance, event or effect that has or will have occurred (or any development that has or will have occurred involving prospective changes) that is materially adverse to the business, operations, financial condition or results of operations of the Company and its subsidiaries, taken as a whole, or could reasonably be expected to have, in the reasonable discretion of the Purchaser, a material adverse effect on the Company or the value of the Shares or, assuming consummation of the Offer or the Proposed Merger, on the Purchaser or any of its affiliates; or

        (4)   there has or will have occurred, and continues to exist:

•

any general suspension of, or limitation on prices for, trading in securities on any national securities exchange or in the over-the-counter market in the United States,



•

any extraordinary or material adverse change in the price of the Shares or the financial markets or major stock exchange indices in the United States, or any change in the general political, market, economic or financial conditions in the United States or abroad that could have a material adverse effect on the business, financial condition or results of operations or prospects of the Company,



•

a change in the general financial, bank or capital market conditions which materially and adversely affects the ability of financial institutions in the United States to extend credit or syndicate loans,



•

a declaration of a banking moratorium or any suspension of payments in respect of banks in the United States (whether or not mandatory),



•

a commencement of a war, armed hostilities, terrorist attack or other national or international crisis involving the United States or a material limitation (whether or not mandatory) by any governmental entity on the extension of credit by banks or other lending institutions, or



•

in the case of any of the foregoing existing at the time of the commencement of the Offer, a material escalation or the worsening thereof; or

        (5)   except as and to the extent publicly disclosed in a report filed by the Company with the Commission prior to the date of this Offer to Purchase, the Company or any of its subsidiaries shall have, directly or indirectly:

•

split, combined or otherwise changed, or authorized or proposed a split, combination or other change of, the Shares or its capitalization,



•

acquired or otherwise caused a reduction in the number of, or authorized or proposed the acquisition or other reduction in the number of, outstanding Shares or other securities,



•

issued, distributed or sold, or authorized, proposed or announced the issuance, distribution or sale of, additional Shares (other than the issuance of Shares under the Company employee stock options outstanding prior to the date of this Offer to Purchase, in accordance with the terms of such stock options as publicly disclosed prior to the date of this Offer to Purchase), shares of

49

any other class of capital stock, other voting securities or any securities convertible into or exchangeable for, or rights, warrants or options to acquire, any of the foregoing,

•

declared or paid, or proposed to declare or pay, any dividend or other distribution, whether payable in cash, securities or other property, on or with respect to any shares of the Company's capital stock (except for regular quarterly cash dividends on the Shares not in excess of $0.05 per share having customary and usual record dates and payment dates),



•

altered or proposed to alter any material term of any outstanding security,



•

issued, distributed or sold, or authorized or proposed the issuance, distribution or sale of any debt securities or any securities convertible into or exchangeable for debt securities or any rights, warrants or options entitling the holder thereof to purchase or otherwise acquire any debt securities or incurred, or authorized or proposed the incurrence of, any debt other than in the ordinary course of business or any debt containing burdensome covenants,



•

authorized, recommended, proposed, entered into or announced its intention to enter into an agreement with respect to, or to cause, any merger (other than the Proposed Merger), consolidation, liquidation, dissolution, business combination, acquisition of assets or securities, disposition of assets, release or relinquishment of any material contractual or other right of the Company or any of its subsidiaries or any comparable event not in the ordinary course of business,



•

authorized, recommended, proposed or entered into, or announced its intention to authorize, recommend, propose or enter into, any agreement or arrangement with any person or group that, in the reasonable judgment of the Purchaser, could adversely affect either the value of the Company or any of its subsidiaries or the value of the Shares to the Purchaser or any of its affiliates,



•

amended or proposed, adopted or authorized any amendment to the Charter or By-Laws of the Company or the articles or by-laws or any other organizational documents of any of its subsidiaries,



•

entered into any employment, severance or similar agreement, arrangement or plan with or for the benefit of any of its employees or entered into or amended any agreements, arrangements or plans so as to provide for increased or accelerated benefits to the employees as a result of or in connection with the transactions contemplated by the Offer, the Proposed Merger or any other business combination, or



•

except as may be required by law, taken any action to terminate or amend any employee benefit plan (as defined in Section 3(2) of the Employee Retirement Income Security Act of 1974, as amended) of the Company or any of its subsidiaries; or

        (6)   the Purchaser shall become aware:

•

that any material contractual right of the Company or any of its subsidiaries shall be impaired or otherwise adversely affected or that any material amount of indebtedness of the Company or any of its subsidiaries shall become accelerated or otherwise become due or become subject to acceleration prior to its stated due date, in any case, with or without notice or the lapse of time or both, as a result of or in connection with the Offer or the consummation by the Purchaser, the Company or any other affiliate of the Company of the Proposed Merger or any other business combination involving the Company and the Purchaser or any of its affiliates,



•

of any covenant, term or condition in any of the instruments or agreements of the Company or any of its subsidiaries that, in the reasonable judgment of the Purchaser, is or may be (whether considered alone or in the aggregate with other such covenants, terms or conditions) materially

50

adverse to either the value of the Company or any of its subsidiaries or the value of the Shares to the Purchaser or any other affiliate of the Purchaser or the consummation by the Purchaser of the Offer or by the Purchaser or any affiliate of the Purchaser of the Proposed Merger or any other business combination (including, without limitation, any event of default that may occur as a result of or in connection with the Offer or the Proposed Merger or any other business combination involving the Company, the Purchaser or any non-competition, exclusivity, co-promotion or marketing or other arrangement), or

•

that any report, document, instrument, financial statement or schedule filed with the Commission contained, when filed, an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary in order to make the statements made therein, in light of the circumstances under which they were made, not misleading; or

        (7)   a tender or exchange offer for any Shares shall have been made or publicly proposed to be made by any person (including the Company or any of its subsidiaries or affiliates), or it shall have been publicly disclosed or the Purchaser shall have otherwise learned that:

•

any person, entity (including the Company or any of its subsidiaries) or "group" (within the meaning of Section 13(d)(3) of the Exchange Act) shall have acquired or proposed to acquire beneficial ownership of more than 5% of any class or series of capital stock of the Company (including the Shares) or any of its subsidiaries, through acquisition of stock, the formation of a group or otherwise, or shall have been granted any right, option or warrant, conditional or otherwise, to acquire beneficial ownership of more than 5% of any class or series of capital stock of the Company (including the Shares) or any of its subsidiaries, other than acquisitions of Shares for bona fide arbitrage purposes only,



•

any such person, entity or group that, prior to the date of this Offer to Purchase, had filed such a Schedule 13G with respect to the Company with the Commission, shall have acquired or proposed to acquire (other than acquisitions of Shares for bona fide arbitrage purposes only), through the acquisition of stock, the formation of a group or otherwise, beneficial ownership of additional shares of any class or series of capital stock of the Company (including the Shares) or any of its subsidiaries constituting 2% or more of any such class or series, or shall have been granted any option, right or warrant, conditional or otherwise, to acquire beneficial ownership of shares of any class or series of capital stock of the Company (including the Shares) or any of its subsidiaries constituting 2% or more of any such class or series,



•

any person, other than the Purchaser or any of its affiliates, shall have made a public announcement reflecting an intent to acquire the Company or any assets or subsidiaries of the Company,



•

any person or group shall have entered into a definitive agreement or an agreement in principle or made a proposal with respect to a tender offer or exchange offer or a merger, consolidation or other business combination with or involving the Company or any of its subsidiaries, or



•

the Company or any of its subsidiaries shall have (i) granted to any person or group proposing a merger or other business combination with or involving the Company or any of its subsidiaries or the purchase of securities or assets of the Company or any of its subsidiaries any type of option, warrant or right which, in the Purchaser's judgment, constitutes a "lock-up" device (including, without limitation, a right to acquire or receive any Shares or other securities, assets or business of the Company or any of its subsidiaries) or (ii) paid or agreed to pay any cash or other consideration to any party in connection with or in any way related to any such business combination or purchase; or

51

        (8)   any material approval, permit, authorization, favorable review or consent of any governmental entity (including those described or referred to in this Section 14) shall not have been obtained on terms satisfactory to the Purchaser, in its reasonable discretion; or

        (9)   (i) the Purchaser or any of its affiliates shall have entered into a definitive agreement or announced an agreement in principle with respect to the Proposed Merger or any other business combination with the Company or any of its affiliates or the purchase of any material portion of the securities or assets of the Company or any of its subsidiaries, or (ii) the Purchaser or any of its affiliates and the Company shall have agreed that the Purchaser shall amend or terminate the Offer or postpone the payment for Shares pursuant thereto;

which, in the reasonable judgment of the Purchaser, in any such case and regardless of the circumstances giving rise to any such condition, makes it inadvisable to proceed with the Offer and/or with such acceptance for payment or payment.

        The foregoing conditions are for the sole benefit of the Purchaser and may be asserted by the Purchaser regardless of the circumstances giving rise to any such conditions and may be waived by the Purchaser in whole or in part at any time and from time to time, in each case, in the exercise of the reasonable discretion of the Purchaser. The failure by the Purchaser at any time to exercise any of the foregoing rights shall not be deemed a waiver of any such right and each such right shall be deemed an ongoing right that may be asserted at any time and from time to time. Any determination by the Purchaser concerning any condition described in this Section 14 shall be binding on all parties. A public announcement may be made of a material change in, or waiver of, such conditions and the Offer may, in certain circumstances, be extended in connection with any such change or waiver. As in the case of all contracts and offers, any binding interpretations of the terms and conditions of the Offer by the Purchaser shall be subject to the review of courts of competent jurisdiction under applicable law.

        Should the Offer be terminated pursuant to the foregoing provisions, all tendered Shares not theretofore accepted for payment shall forthwith be returned by the Depositary to the tendering stockholders.

15.   CERTAIN LEGAL MATTERS; REQUIRED REGULATORY APPROVALS.

        Except as set forth in this Offer to Purchase, based on its review of publicly available filings by the Company with the Commission and other publicly available information regarding the Company, the Purchaser is not aware of any licenses or regulatory permits that would be material to the business of the Company and its subsidiaries, taken as a whole, and that might be adversely affected by the Purchaser's acquisition of Shares (and the indirect acquisition of the stock of the Company's subsidiaries) as contemplated herein, or, except to the extent required by any foreign regulatory authorities, any filings, approvals or other actions by or with any domestic, foreign or supranational governmental authority or administrative or regulatory agency that would be required prior to the acquisition of Shares (or the indirect acquisition of the stock of the Company's subsidiaries) by the Purchaser pursuant to the Offer as contemplated herein. Should any such approval or other action be required, there can be no assurance that any such additional approval or action, if needed, would be obtained without substantial conditions or that adverse consequences might not result to the Company's business, or that certain parts of the Company's or the Purchaser's business might not have to be disposed of or held separate or other substantial conditions complied with in order to obtain such approval or action or in the event that such approvals were not obtained or such actions were not taken. The Purchaser does not presently intend, however, to delay the purchase of Shares tendered pursuant to the Offer pending the receipt of any such approval or the taking of any such action (subject to the Purchaser's right to delay or decline to purchase Shares if any of the conditions in the Introduction shall not have been satisfied or any of the events in Section 14 shall have occurred). The Purchaser's obligation to purchase and pay for Shares is subject to certain conditions which may be

52

applicable under such circumstances. See Introduction and Section 14 for a description of certain conditions to the Offer.

        Antitrust.    Based upon information filed by the Company with the Commission, the Purchaser believes that the acquisitions of Shares and the Proposed Merger were subject to the pre-merger notification and reporting obligations under the Hart-Scott-Rodino Antitrust Improvement Act. The notification and reporting obligations have been complied with and the waiting period under the Hart-Scott-Rodino Antitrust Improvement Act expired on December 6, 2006.

        State Anti-Takeover Laws.    A number of states (including Delaware, where the Company is incorporated) have adopted takeover laws and regulations which purport, to varying degrees, to be applicable to attempts to acquire securities of corporations which are incorporated in such states or which have substantial assets, security holders, principal executive offices or principal places of business therein. See Section 11 for more information.

        Other Notices.    G-I Holdings Inc., the Purchaser's indirect parent company, filed a voluntary petition for reorganization under Chapter 11 of the U.S. Bankruptcy Code in the United States Bankruptcy Court for the District of New Jersey (the "Bankruptcy Court") due to asbestos-related bodily injury claims brought against it relating to the inhalation of asbestos fiber. Pursuant to that certain Order Granting Preliminary Injunction entered by the Bankruptcy Court on February 22, 2002 (as amended), the Purchaser, must provide written notice to the Statutory Committee of Asbestos Claimants prior to consummating any refinancing.

16.   CERTAIN FEES AND EXPENSES.

        Bear, Stearns & Co. Inc. is acting as the Dealer Manager in connection with the Offer and as one of the Lead Arrangers under the Credit Facilities. Customary compensation will be paid to the Dealer Manager in light of their overall role in the Offer and related transactions. The Purchaser has also agreed to reimburse the Dealer Manager for reasonable out-of-pocket expenses in connection with the Offer and to indemnify the Dealer Manager against certain liabilities and expenses, including liabilities under the federal securities laws.

        D. F. King & Co., Inc. has been retained by the Purchaser as Information Agent in connection with the Offer. The Information Agent may contact holders of Shares by mail, telephone, telex, telegraph and personal interview and may request brokers, dealers and other nominee stockholders to forward material relating to the Offer to beneficial owners. Customary compensation will be paid for all such services in addition to reimbursement of reasonable out-of-pocket expenses. The Purchaser has agreed to indemnify the Information Agent against certain liabilities and expenses, including liabilities under the federal securities laws.

        The Bank of New York has been retained by the Purchaser as the Depositary. The Depositary has not been retained to make solicitations or recommendations in its role as Depositary. The Depositary will receive reasonable and customary compensation for its services in connection with the Offer, will be reimbursed for its reasonable out-of-pocket expenses, and will be indemnified against certain liabilities and expenses in connection therewith.

        The Purchaser will not pay any fees or commissions to any broker, dealer or other person (other than the Dealer Manager and the Information Agent) for soliciting tenders of Shares pursuant to the Offer. Brokers, dealers, commercial banks and trust companies and other nominees will, upon request, be reimbursed by the Purchaser for customary clerical and mailing expenses incurred by them in forwarding materials to their customers.

53

17.   MISCELLANEOUS.

        The Offer is being made solely by this Offer to Purchase and the related Letter of Transmittal and is being made to all holders of the Shares (excluding Shares beneficially owned by BMCA). This Offer is not being made to (nor will tenders be accepted from or on behalf of) holders of Shares in any jurisdiction in which the making of this Offer or the acceptance thereof would not be in compliance with the securities or other laws of such jurisdiction. The Purchaser is not aware of any jurisdiction where the making of the Offer is prohibited by any administrative or judicial action pursuant to any valid state statute. If the Purchaser becomes aware of any valid state statute prohibiting the making of the Offer or the acceptance of the Shares pursuant thereto, the Purchaser will make a good faith effort to comply with such state statute. If, after such good faith effort the Purchaser cannot comply with any such state statute, the Offer will not be made to (nor will tenders be accepted from or on behalf of) the holders of Shares in such state. In those jurisdictions where the applicable laws require that the Offer be made by a licensed broker or dealer, the Offer shall be deemed to be made on behalf of the Purchaser by the Dealer Manager or one or more registered brokers or dealers licensed under the laws of such jurisdiction.

        NO PERSON HAS BEEN AUTHORIZED TO GIVE ANY INFORMATION OR MAKE ANY REPRESENTATION ON BEHALF OF THE PURCHASER NOT CONTAINED IN THIS OFFER TO PURCHASE OR IN THE LETTER OF TRANSMITTAL, AND IF GIVEN OR MADE, SUCH INFORMATION OR REPRESENTATION MUST NOT BE RELIED UPON AS HAVING BEEN AUTHORIZED.

        The Purchaser has filed with the Commission a Tender Offer Statement on Schedule TO, together with exhibits, pursuant to Rule 14d-3 of the General Rules and Regulations promulgated under the Exchange Act, furnishing certain additional information with respect to the Offer, and may file amendments thereto. Such Schedule TO and any amendments thereto, including exhibits, may be examined and copies may be obtained from the same places and in the same manner as set forth in Section 8.

SOLICITATION OF PROXIES

        THE OFFER DOES NOT CONSTITUTE A SOLICITATION OF PROXIES FOR ANY MEETING OF THE COMPANY'S STOCKHOLDERS. ANY SUCH SOLICITATION WHICH THE PURCHASER OR ANY OF ITS AFFILIATES MIGHT SEEK WOULD BE MADE ONLY PURSUANT TO SEPARATE PROXY MATERIALS COMPLYING WITH THE REQUIREMENTS OF SECTION 14(A) OF THE EXCHANGE ACT.

BMCA ACQUISITION SUB INC.

January 18, 2007

54

SCHEDULE 1

DIRECTORS AND EXECUTIVE OFFICERS OF THE PURCHASER AND THE PARENT
AND DIRECTORS, OFFICERS AND GENERAL PARTNERS OF CERTAIN AFFILIATES

1.     BMCA Acquisition Sub Inc.

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
John F. Rebele 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, Chief Financial Officer, Chief Administrative Officer and Director, since 2006. Senior Vice President, Chief Financial Officer and Director of BMCA Acquisition Inc., since 2006.
	Senior Vice President, Chief Financial Officer and Director of Building Materials Corporation of America, since 2001; Chief Administrative Officer, since 2005; Vice President, Finance from 1998-2001.
Robert B. Tafaro 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Chief Executive Officer, President and Director, since 2006. Chief Executive Officer, President and Director of BMCA Acquisition Inc., since 2006.
	Chief Executive Officer and President of Building Materials Corporation of America, since 2006; Director, for more than 5 years; Chief Operating Officer Executive Vice President, Roofing Systems, from 2005-2006; Senior Vice President and General Manager, Roofing Systems Sales from 2003-2005; Senior Vice President and General Manager, Residential Systems from 2000-2003.
	Chief Executive Officer, President and Director of BMCA Holdings Corporation, since 2006.
	Director of G-I Holdings Inc., since 2006.
Douglas H. Greeff 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, since 2007. Senior Vice President of BMCA Acquisition Inc., since 2007. Senior Vice President of Building Materials Corporation of America, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of BMCA Holdings Corporation, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G-I Holdings Inc., since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G Holdings Inc., since 2007.

I-1

Executive Vice President – Strategic Finance of Revlon Inc. from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.

Revlon Inc.
237 Park Avenue
New York, NY 10017

Executive Vice President – Strategic Finance of Revlon Consumer Products Corporation from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.

Revlon Consumer Products Corporation
237 Park Avenue
New York, NY 10017

Executive Vice President – Finance and Treasurer of International Specialty Products Inc., since 2007.

International Specialty Products Inc.
1361 Alps Road
Wayne, NJ 07470

2.     BMCA Acquisition Inc.

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
John F. Rebele 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, Chief Financial Officer and Director, since 2006. Senior Vice President, Chief Financial Officer, Chief Administrative Officer and Director of BMCA Acquisition Sub Inc., since 2006.
	Senior Vice President, Chief Financial Officer and Director of Building Materials Corporation of America, since 2001; Chief Administrative Officer, since 2005; Vice President, Finance from 1998-2001.
Robert B. Tafaro 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Chief Executive Officer, President and Director, since 2006. Chief Executive Officer, President and Director of BMCA Acquisition Sub Inc., since 2006. Chief Executive Officer and President of Building Materials Corporation of America, since 2006; Director, for more than 5 years; Chief Operating Officer Executive Vice President, Roofing Systems, from 2005-2006; Senior Vice President and General Manager, Roofing Systems Sales from 2003-2005; Senior Vice President and General Manager, Residential Systems from 2000-2003.
	Chief Executive Officer, President and Director of BMCA Holdings Corporation, since 2006.

I-2

	Director of G-I Holdings Inc., since 2006.
Douglas H. Greeff 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, since 2007. Senior Vice President of BMCA Acquisition Sub Inc., since 2007. Senior Vice President of Building Materials Corporation of America, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of BMCA Holdings Corporation, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G-I Holdings Inc., since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G Holdings Inc., since 2007.
	Executive Vice President – Strategic Finance of Revlon Inc. from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Inc. 237 Park Avenue New York, NY 10017
	Executive Vice President – Strategic Finance of Revlon Consumer Products Corporation from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Consumer Products Corporation 237 Park Avenue New York, NY 10017
	Executive Vice President – Finance and Treasurer of International Specialty Products Inc., since 2007.
	International Specialty Products Inc. 1361 Alps Road Wayne, NJ 07470

3.     Building Materials Corporation of America

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
David A. Harrison 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, Marketing, Contractor Services and Corporate Development and Director, for more than 5 years; President of GAF Materials Corporation (Canada), for more than 5 years.
	GAF Materials Corporation (Canada) 1361 Alps Road Wayne, NJ 07470

I-3

John F. Rebele 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, Chief Financial Officer and Director, since 2001; Chief Administrative Officer, since 2005; Vice President, Finance from 1998-2001. Senior Vice President, Chief Financial Officer, Chief Administrative Officer and Director of BMCA Acquisition Sub Inc., since 2006.
	Senior Vice President, Chief Financial Officer and Director of BMCA Acquisition Inc., since 2006.
Robert B. Tafaro 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Chief Executive Officer and President, since 2006; Director, for more than 5 years; Chief Operating Officer Executive Vice President, Roofing Systems, from 2005-2006; Senior Vice President and General Manager, Roofing Systems Sales from 2003-2005; Senior Vice President and General Manager, Residential Systems from 2000-2003.
	Chief Executive Officer, President and Director of BMCA Acquisition Sub Inc., since 2006.
	Chief Executive Officer, President and Director of BMCA Acquisition Inc., since 2006.
	Chief Executive Officer, President and Director of BMCA Holdings Corporation, since 2006.
	Director of G-I Holdings Inc., since 2006.
Kenneth E. Walton 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, Operations and Director, for more than 5 years.
Douglas H. Greeff 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, since 2007. Senior Vice President of BMCA Acquisition Sub Inc., since 2007. Senior Vice President of BMCA Acquisition Inc., since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of BMCA Holdings Corporation, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G-I Holdings Inc., since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G Holdings Inc., since 2007.
	Executive Vice President – Strategic Finance of Revlon Inc. from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Inc. 237 Park Avenue New York, NY 10017

I-4

Executive Vice President – Strategic Finance of Revlon Consumer Products Corporation from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.

Revlon Consumer Products Corporation
237 Park Avenue
New York, NY 10017

Executive Vice President – Finance and Treasurer of International Specialty Products Inc., since 2007.

International Specialty Products Inc.
1361 Alps Road
Wayne, NJ 07470

4.     Heyman Investment Associates Limited Partnership

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
Samuel J. Heyman 667 Madison Avenue, 12th Floor New York, NY 10021 U.S. Citizen	General Partner. Chief Executive Officer, President, Secretary and Director of G-I Holdings Inc., since 2005. Mr. Heyman held the position of Executive Officer of G-I Holdings Inc. at various points prior to 2005.
	Chief Executive Officer, President, Secretary and Director of G Holdings Inc., since 2005.
	General Partner of Heyman Holdings Associates Limited Partnership.

5.     BMCA Holdings Corporation

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
Robert B. Tafaro 300 Delaware Avenue, Suite 303 Wilmington, DE 19801 U.S. Citizen	Chief Executive Officer, President and Director, since 2006. Chief Executive Officer, President and Director of BMCA Acquisition Sub Inc., since 2006.
	Chief Executive Officer, President and Director of BMCA Acquisition Inc., since 2006.

I-5

	Chief Executive Officer, President and Director of BMCA Acquisition Inc., since 2006. Chief Executive Officer and President of Building Materials Corporation of America, since 2006; Director, for more than 5 years; Chief Operating Officer Executive Vice President, Roofing Systems, from 2005-2006; Senior Vice President and General Manager, Roofing Systems Sales from 2003-2005; Senior Vice President and General Manager, Residential Systems from 2000-2003.
	Director of G-I Holdings Inc., since 2006.
Douglas H. Greeff 300 Delaware Avenue, Suite 303 Wilmington, DE 19801 U.S. Citizen	Senior Vice President, Chief Financial Officer and Treasurer, since 2007. Senior Vice President of BMCA Acquisition Sub Inc., since 2007. Senior Vice President of BMCA Acquisition Inc., since 2007.
	Senior Vice President of Building Materials Corporation of America, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G-I Holdings Inc., since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G Holdings Inc., since 2007.
	Executive Vice President – Strategic Finance of Revlon Inc. from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Inc. 237 Park Avenue New York, NY 10017
	Executive Vice President – Strategic Finance of Revlon Consumer Products Corporation from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Consumer Products Corporation 237 Park Avenue New York, NY 10017
	Executive Vice President – Finance and Treasurer of International Specialty Products Inc., since 2007.
	International Specialty Products Inc. 1361 Alps Road Wayne, NJ 07470

I-6

6.     G-I Holdings Inc.

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
Samuel J. Heyman 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Chief Executive Officer, President, Secretary and Director, since 2005. Mr. Heyman held the position of Executive Officer at various points prior to 2005. General Partner of Heyman Investment Associates Limited Partnership.
	Chief Executive Officer, President, Secretary and Director of G Holdings Inc., since 2005.
	General Partner of Heyman Holdings Associates Limited Partnership.
Robert B. Tafaro 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Director, since 2006. Chief Executive Officer, President and Director of BMCA Acquisition Sub Inc., since 2006. Chief Executive Officer, President and Director of BMCA Acquisition Inc., since 2006.
	Chief Executive Officer and President of Building Materials Corporation of America, since 2006; Director, for more than 5 years; Chief Operating Officer Executive Vice President, Roofing Systems, from 2005-2006; Senior Vice President and General Manager, Roofing Systems Sales from 2003-2005; Senior Vice President and General Manager, Residential Systems from 2000-2003.
	Chief Executive Officer, President and Director of BMCA Holdings Corporation, since 2006.

I-7

Douglas H. Greeff 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, Chief Financial Officer and Treasurer, since 2007. Senior Vice President of BMCA Acquisition Sub Inc., since 2007. Senior Vice President of BMCA Acquisition Inc., since 2007.
	Senior Vice President of Building Materials Corporation of America, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of BMCA Holdings Corporation, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G Holdings Inc., since 2007.
	Executive Vice President – Strategic Finance of Revlon Inc. from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Inc. 237 Park Avenue New York, NY 10017
	Executive Vice President – Strategic Finance of Revlon Consumer Products Corporation from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Consumer Products Corporation 237 Park Avenue New York, NY 10017
	Executive Vice President – Finance and Treasurer of International Specialty Products Inc., since 2007.
	International Specialty Products Inc. 1361 Alps Road Wayne, NJ 07470

I-8

7.     G Holdings Inc.

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
Samuel J. Heyman 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Chief Executive Officer, President, Secretary and Director, since 2005. General Partner of Heyman Investment Associates Limited Partnership. Chief Executive Officer, President, Secretary and Director of G-I Holdings Inc., since 2005.
	Mr. Heyman held the position of Executive Officer of G-I Holdings Inc. at various points prior to 2005.
	General Partner of Heyman Holdings Associates Limited Partnership.
Douglas H. Greeff 1361 Alps Road Wayne, NJ 07470 U.S. Citizen	Senior Vice President, Chief Financial Officer and Treasurer, since 2007. Senior Vice President of BMCA Acquisition Sub Inc., since 2007. Senior Vice President of BMCA Acquisition Inc., since 2007.
	Senior Vice President of Building Materials Corporation of America, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of BMCA Holdings Corporation, since 2007.
	Senior Vice President, Chief Financial Officer and Treasurer of G-I Holdings Inc., since 2007.
	Executive Vice President – Strategic Finance of Revlon Inc. from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Inc. 237 Park Avenue New York, NY 10017
	Executive Vice President – Strategic Finance of Revlon Consumer Products Corporation from 2003-2005; Executive Vice President and Chief Financial Officer from 2000-2003.
	Revlon Consumer Products Corporation 237 Park Avenue New York, NY 10017
	Executive Vice President – Finance and Treasurer of International Specialty Products Inc., since 2007.
	International Specialty Products Inc. 1361 Alps Road Wayne, NJ 07470

I-9

8.     Heyman Holdings Associates Limited Partnership

Name, Citizenship and Current Business Address	Present Principal Occupation or Employment; Material Positions Held During the Past Five Years and Business Addresses Thereof
Samuel J. Heyman 667 Madison Avenue, 12th Floor New York, NY 10021 U.S. Citizen	General Partner. General Partner of Heyman Investment Associates Limited Partnership. Chief Executive Officer, President, Secretary and Director of G- I Holdings Inc., since 2005. Mr. Heyman held the position of Executive Officer of G-I Holdings Inc. at various points prior to 2005.
	Chief Executive Officer, President, Secretary and Director of G Holdings Inc., since 2005.

I-10

SCHEDULE II

TRANSACTIONS BY PURCHASER'S AFFILIATES INVOLVING COMPANY SHARES

        During the period from July 27, 2006 through November 1, 2006, the Purchaser's affiliates have made the following purchases and sales of Shares on the open market:

Transaction Type	Transaction Date	Number of Shares Purchased/Sold		Price Per Share ($)
Purchase	7/27/2006	9,700		24.75
Purchase	7/31/2006	300		24.88
Purchase	8/01/2006	10,500		24.60
Purchase	8/03/2006	200		24.87
Purchase	8/04/2006	54,600		26.01
Purchase	8/07/2006	22,700		26.02
Purchase	8/08/2006	50,000		25.67
Purchase	8/09/2006	44,800		25.30
Purchase	8/10/2006	33,900		24.90
Purchase	8/11/2006	21,700		24.93
Purchase	8/14/2006	35,500		24.98
Purchase	8/15/2006	14,000		25.24
Purchase	8/16/2006	1,200		25.75
Purchase	8/17/2006	30,100		26.52
Purchase	8/18/2006	31,000		27.04
Purchase	8/18/2006	203,700		27.03
Purchase	8/21/2006	100,900		26.59
Purchase	8/22/2006	30,200		26.81
Purchase	8/23/2006	24,000		26.62
Purchase	8/24/2006	58,000		26.61
Purchase	8/25/2006	27,800		26.70
Purchase	8/28/2006	20,500		26.98
Purchase	8/29/2006	30,300		26.92
Purchase	8/30/2006	3,800		27.63
Purchase	8/31/2006	34,600		28.17
Purchase	9/01/2006	9,300		28.13
Sale	9/01/2006	(9,300	)	28.40
Sale	9/01/2006	(15,700	)	28.40
Purchase	9/05/2006	23,200		28.58
Purchase	9/06/2006	30,000		28.11
Purchase	9/07/2006	35,600		27.89
Purchase	9/08/2006	4,500		27.91
Purchase	9/11/2006	20,100		27.86
Purchase	9/12/2006	1,800		27.98
Purchase	9/18/2006	10,800		29.04
Purchase	9/19/2006	19,100		28.22
Sale	9/20/2006	(2,600	)	28.82
Sale	10/25/2006	(16,800	)	26.51
Purchase	10/25/2006	16,800		26.28
Purchase	10/26/2006	60,000		27.01
Purchase	10/27/2006	200,000		24.54
Purchase	10/27/2006	477,500		24.95
Purchase	10/30/2006	156,300		25.05
Purchase	10/31/2006	96,800		25.13
Purchase	11/01/2006	112,400		25.22
Total		2,123,800

II-1

        Facsimile copies of the Letter of Transmittal, properly completed and duly executed, will be accepted. The Letter of Transmittal, certificates for Shares and any other required documents should be sent or delivered by each stockholder of the Company or his broker, dealer, commercial bank, trust company or other nominee to the Depositary at one of its addresses set forth below:

The Depositary for the Offer is:

The Bank of New York

By Mail:
The Bank of New York
Reorganization Services
P.O. Box 859208
Braintree, MA 02185-9208
(registered or certified mail recommended) By Overnight Courier:
The Bank of New York
Reorganization Services
161 Bay State Drive
Braintree, MA 02184

By Facsimile Transmission:
(For Eligible Institutions Only)
(781) 380-3388

Confirm Facsimile By Telephone:
(781) 843-1833 Ext. 200 By Hand:
The Bank of New York
Reorganization Services
101 Barclay Street, 1-E
Receive and Deliver Window
New York, NY 10286

Any questions or requests for assistance may be directed to the Information Agent or the Dealer Manager at their respective addresses and telephone numbers listed below. Additional copies of this Offer to Purchase, the Letter of Transmittal and other tender offer materials may be obtained from the Information Agent as set forth below, and will be furnished promptly at the Purchaser's expense. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance, concerning the Offer.

The Information Agent for the Offer is:

D. F. King & Co., Inc.
48 Wall Street
New York, NY 10005
(212) 269-5550
Toll-Free: (888) 628-9011
E-MAIL: info@dfking.com

The Dealer Manager for the Offer is:

Bear, Stearns & Co. Inc.
383 Madison Ave., 8th Floor
New York, NY 10179
(212) 272-5112
Toll-Free: (877) 696-BEAR

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IMPORTANT
TABLE OF CONTENTS
SUMMARY TERM SHEET
INTRODUCTION
THE OFFER
SOLICITATION OF PROXIES
DIRECTORS AND EXECUTIVE OFFICERS OF THE PURCHASER AND THE PARENT AND DIRECTORS, OFFICERS AND GENERAL PARTNERS OF CERTAIN AFFILIATES
TRANSACTIONS BY PURCHASER'S AFFILIATES INVOLVING COMPANY SHARES

EX-99.(A)(1)(B)

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Exhibit (a)(1)(B)

Letter of Transmittal

to
Tender Shares of Common Stock
(including the Associated Series A Participating Preferred Stock Purchase Rights)
of
ELKCORP

PURSUANT TO THE OFFER TO PURCHASE
DATED JANUARY 18, 2007
AT
$42.00 NET PER SHARE
(CUSIP Number of Class of Securities: 287456107)

by
BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.

        THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, FEBRUARY 14, 2007, UNLESS THE OFFER IS EXTENDED.

The Depositary For The Offer Is:

THE BANK OF NEW YORK

By Mail: The Bank of New York Reorganization Services P.O. Box 859208 Braintree, MA 02185-9208	By Overnight Courier: The Bank of New York Reorganization Services 161 Bay State Drive Braintree, MA 02184	By Hand: The Bank of New York Reorganization Services 101 Barclay Street, 1-E Receive and Deliver Window New York, NY 10286
	By Facsimile Transmission: (For Eligible Institutions Only)
	(781) 380-3388
	To Confirm Facsimile Only:
	(781) 843-1833 Ext. 200

DESCRIPTION OF SHARES TENDERED
Name(s) and Address(es) of Registered Holder(s) (Please fill in, if blank, exactly as Name(s) appear(s) on Stock Certificate(s))		Stock Certificate(s) Tendered (Attach additional list if necessary)
		Stock Certificate Number(s)*	Total Number of Shares Evidenced by Stock Certificate(s)*	Number of Shares Tendered**
		Total Shares
*	Need not be completed by Stockholders tendering Shares by book-entry transfer.
**	Unless otherwise indicated, it will be assumed that all Shares evidenced by any Stock Certificates delivered to the Depositary are being tendered. See Instruction 5.

DELIVERY OF THIS LETTER OF TRANSMITTAL TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE OR TRANSMISSION OF INSTRUCTIONS VIA A FACSIMILE TO A NUMBER OTHER THAN SET FORTH ABOVE WILL NOT CONSTITUTE A VALID DELIVERY TO THE DEPOSITARY FOR THE OFFER. YOU MUST SIGN THIS LETTER OF TRANSMITTAL IN THE APPROPRIATE SPACE PROVIDED BELOW, WITH SIGNATURE GUARANTEE IF REQUIRED, AND COMPLETE THE SUBSTITUTE FORM W-9 SET FORTH BELOW.

THE INSTRUCTIONS ACCOMPANYING THIS LETTER OF TRANSMITTAL SHOULD BE READ CAREFULLY BEFORE THIS LETTER OF TRANSMITTAL IS COMPLETED.

THIS LETTER OF TRANSMITTAL IS TO BE COMPLETED BY STOCKHOLDERS EITHER IF CERTIFICATES EVIDENCING SHARES (AS DEFINED BELOW) ARE TO BE FORWARDED HEREWITH OR IF DELIVERY OF SHARES IS TO BE MADE BY BOOK-ENTRY TRANSFER TO THE DEPOSITARY'S ACCOUNT AT THE DEPOSITORY TRUST COMPANY ("DTC") (THE "BOOK-ENTRY TRANSFER FACILITY") PURSUANT TO THE BOOK-ENTRY TRANSFER PROCEDURE DESCRIBED IN SECTION 3 OF THE OFFER TO PURCHASE (AS DEFINED BELOW). DELIVERY OF DOCUMENTS TO THE BOOK-ENTRY TRANSFER FACILITY DOES NOT CONSTITUTE DELIVERY TO THE DEPOSITARY.

PARTICIPANTS IN THE ELKCORP EMPLOYEE STOCK OWNERSHIP PLAN (THE "ESOP") MUST TENDER THEIR SHARES HELD INDIRECTLY IN THE ESOP THROUGH THE TRUSTEE DIRECTION FORM, NOT THIS LETTER OF TRANSMITTAL.

        Holders of outstanding shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp (the "Company"), (i) if certificates evidencing the Shares are not immediately available, (ii) if Share Certificates (as defined below) and all other required documents cannot be delivered to The Bank of New York (the "Depositary") or (iii) if the procedure for book-entry transfer cannot be completed on a timely basis or time will not permit all required documents to reach the Depositary on or prior to the Expiration Date (as defined in the Offer to Purchase, dated January 18, 2007 (the "Offer to Purchase")), must deliver their Shares according to the guaranteed delivery procedure set forth in Section 3 of the Offer to Purchase.

o    CHECK HERE IF SHARES ARE BEING DELIVERED BY BOOK-ENTRY TRANSFER TO THE DEPOSITARY'S ACCOUNT AT ONE OF THE BOOK-ENTRY TRANSFER FACILITIES AND COMPLETE THE FOLLOWING:

Name(s) of Tendering Institution:

Account Number:

Transaction Code Number:

o    CHECK HERE IF SHARES ARE BEING TENDERED PURSUANT TO A NOTICE OF GUARANTEED DELIVERY PREVIOUSLY SENT TO THE DEPOSITARY AND COMPLETE THE FOLLOWING:

Name(s) of Registered Holder(s):

Window Ticket Number (if any):

Date of Execution of Notice of Guaranteed Delivery:

Name of Institution which Guaranteed Delivery:

If Delivered by Book-Entry Transfer, Check Box: o

Account Number:

Transaction Code Number:

NOTE:    SIGNATURES MUST BE PROVIDED AT THE END OF THIS LETTER OF TRANSMITTAL. PLEASE READ THE INSTRUCTIONS SET FORTH IN THIS LETTER OF TRANSMITTAL CAREFULLY.

1

Ladies and Gentlemen:

        The undersigned hereby tenders to BMCA Acquisition Sub Inc., a Delaware corporation (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), the above-described shares of common stock, par value $1.00 per share ("Shares") of ElkCorp, a Delaware corporation (the "Company"), pursuant to the Purchaser's offer to purchase all of the outstanding Shares, and the associated Series A Participating Preferred Stock purchase rights, at $42.00 per Share, net to the seller in cash (subject to applicable withholding taxes), without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated January 18, 2007 (the "Offer to Purchase"), receipt of which is hereby acknowledged, and in this Letter of Transmittal (which together, as each may be amended or supplemented from time to time, constitute the "Offer"). The Purchaser reserves the right to transfer or assign, in whole or from time to time in part, to one or more of its affiliates the right to purchase Shares tendered pursuant to the Offer, but any such transfer or assignment will not relieve the Purchaser of its obligations under the Offer or prejudice your rights to receive payment for Shares validly tendered and accepted for payment.

        Subject to, and effective upon, acceptance for payment of Shares tendered herewith, in accordance with the terms of the Offer (including, if the Offer is extended or amended, the terms and conditions of such extension or amendment), the undersigned hereby sells, assigns and transfers to, or upon the order of, the Purchaser all right, title and interest in and to all Shares that are being tendered hereby and all dividends, distributions (including, without limitation, distributions of additional Shares) and rights declared, paid or distributed in respect of such Shares on or after the date of the Offer (collectively, "Distributions") and irrevocably appoints the Depositary as the true and lawful agent and attorney-in-fact of the undersigned with respect to such Shares and any and all Distributions, with full power of substitution (such power of attorney being deemed to be an irrevocable power coupled with an interest), to (i) deliver Share Certificates evidencing such Shares and all Distributions, or transfer ownership of such Shares and all Distributions on the account books maintained by a Book-Entry Transfer Facility, together, in either case, with all accompanying evidences of transfer and authenticity, to or upon the order of the Purchaser, (ii) present such Shares and all Distributions for transfer on the books of the Company and (iii) receive all benefits and otherwise exercise all rights of beneficial ownership of such Shares and all Distributions, all in accordance with the terms of the Offer.

        By executing this Letter of Transmittal, the undersigned irrevocably appoints designees of the Purchaser as attorneys-in-fact and proxies of the undersigned, in the manner set forth in this Letter of Transmittal, each with full power of substitution, to the full extent of the undersigned's rights with respect to (a) the Shares tendered by the undersigned and accepted for payment by the Purchaser and (b) any and all non-cash dividends, distributions, rights or other securities issued or issuable on or after the date of the Offer to Purchase in respect of such tendered and accepted Shares. All such proxies shall be considered coupled with an interest in the tendered Shares. This appointment will be effective if, when and only to the extent that the Purchaser accepts such Shares for payment pursuant to the Offer. Upon such acceptance for payment, all prior proxies given by such stockholder with respect to such Shares and other securities will, without further action, be revoked, and no subsequent proxies may be given nor any subsequent written consents executed (and, if given or executed, will not be deemed effective). The designees of the Purchaser will, with respect to the Shares and other securities for which the appointment is effective, be empowered to exercise all voting and other rights of such stockholder as they, in their sole discretion, may deem proper at any annual, special, adjourned or postponed meeting of the Company's stockholders, and the Purchaser reserves the right to require that in order for Shares or other securities to be deemed validly tendered, immediately upon the Purchaser's acceptance for payment of such Shares, the Purchaser must be able to exercise full voting rights with respect to such Shares. The foregoing proxies are effective only upon acceptance for payment of Shares pursuant to the Offer.

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        The undersigned hereby represents and warrants that the undersigned has full power and authority to tender, sell, assign and transfer Shares tendered hereby and all Distributions, and that when such Shares are accepted for payment by the Purchaser, the Purchaser will acquire good, marketable and unencumbered title thereto and to all Distributions, free and clear of all liens, restrictions, charges and encumbrances (other than those resulting from action of the Purchaser or any of its subsidiaries), and that none of such Shares and Distributions will be subject to any adverse claim (other than those resulting from action of the Purchaser or any of its affiliates). The undersigned, upon request, shall execute and deliver all additional documents deemed by the Depositary or the Purchaser to be necessary or desirable to complete the sale, assignment and transfer of Shares tendered hereby and all Distributions. In addition, the undersigned shall remit and transfer promptly to the Depositary for the account of the Purchaser, all Distributions in respect of Shares tendered hereby, accompanied by appropriate documentation of transfer, and, pending such remittance and transfer or appropriate assurance thereof, the Purchaser shall be entitled to all rights and privileges as owner of each such Distribution and may withhold the entire purchase price of Shares tendered hereby or deduct from such purchase price the amount or value of such Distribution as determined by the Purchaser in its sole discretion.

        All authority herein conferred or agreed to be conferred shall survive the death or incapacity of the undersigned, and any obligation of the undersigned hereunder shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned. Except as stated in the Offer, this tender is irrevocable.

        The undersigned understands that tenders of Shares pursuant to any one of the procedures described in Section 3 of the Offer to Purchase and in the instructions hereto will constitute a binding agreement between the undersigned and the Purchaser upon the terms and subject to the conditions of the Offer, including, without limitation, the undersigned's representation and warranty that the undersigned owns all Shares being tendered.

3

SPECIAL PAYMENT INSTRUCTIONS
(SEE INSTRUCTIONS 1, 6, 7 AND 8)

            To be completed ONLY if the check for the purchase price of Shares purchased or Share Certificates evidencing Shares not tendered or not purchased are to be issued in the name of someone other than the undersigned. Or if Shares tendered hereby and delivered by book-entry transfer that are not purchased are to be returned by credit to an account maintained at the Book-Entry Transfer Facility other than the account indicated above.

Issue o  Check o  Share Certificate(s) to:

Name: (Print)

Address:

(Include Zip Code)

(Taxpayer Identification or Social Security Number) (See Substitute Form W-9 Included Herein)
o	Credit Shares delivered by book-entry transfer and not purchased to the Holders Book-Entry Transfer Facility Account.
Account Number

SPECIAL DELIVERY INSTRUCTIONS
(SEE INSTRUCTIONS 1, 6, 7 AND 8)

            To be completed ONLY if the check for the purchase price of Shares purchased or Share Certificates evidencing Shares not tendered or not purchased are to be mailed to someone other than the undersigned, or to the undersigned at an address other than that shown under "Description of Shares Tendered."

Mail o  Check o  Share Certificate(s) to:

Name:	(Print)
Address:
	(Include Zip Code)

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IMPORTANT:
STOCKHOLDERS
SIGN HERE (PLEASE COMPLETE
SUBSTITUTE FORM W-9 INCLUDED HEREIN)

Signature(s) of Holder(s)

Date:

, 200

        (Must be signed by registered holder(s) exactly as name(s) appear(s) on Share Certificates or on a security position listing or by a person(s) authorized to become registered holder(s) by certificates and documents transmitted herewith. If signature is by a trustee, executor, administrator, guardian, attorney-in-fact, officer of a corporation or other person acting in a fiduciary or representative capacity, please provide the following information. See Instruction 6.)

Name(s): (Please Print)

Capacity (full title):

Address:

(Include Zip Code)

Area Code and Tel. No.:

Tax Identification or Social Security Number:

(SEE SUBSTITUTE FORM W-9
INCLUDED HEREIN)

GUARANTEE OF SIGNATURE(S)
(IF REQUIRED—SEE INSTRUCTIONS 1 AND 6)

FOR USE BY FINANCIAL INSTITUTIONS ONLY.
PLACE MEDALLION GUARANTEE IN SPACE BELOW.

Authorized Signature:

Name:
	(Please Print)

Name of Firm:

Address: (Include Zip Code)

Area Code and Tel. No.:

     Date:

, 200

5

INSTRUCTIONS

FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER

1.     Guarantee of Signatures.

        Except as otherwise provided below, all signatures on this Letter of Transmittal must be guaranteed by a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a participant in the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program or the Stock Exchange Medallion Program or any other "eligible guarantor institution" (as such term is defined in Rule 17Ad-15 under the Securities Exchange Act of 1934, as amended) (each an "Eligible Institution"). Signatures on this Letter of Transmittal need not be guaranteed (i) if this Letter of Transmittal is signed by the registered holder(s) of the Shares (which term, for purposes of this document, shall include any participant in the Book-Entry Transfer Facility whose name appears on a security position listing as the owner of Shares) tendered herewith and such holder(s) have not completed the instruction entitled "Special Payment Instructions" or "Special Delivery Instructions" on this Letter of Transmittal or (ii) if such Shares are tendered for the account of an Eligible Institution. See Instruction 6.

2.     Delivery of Letter of Transmittal and Shares.

        This Letter of Transmittal is to be used if share certificates representing one or more Shares (the "Share Certificates") are to be forwarded herewith or, unless an Agent's Message (as defined in the Offer to Purchase) is utilized, if deliveries are to be made by book-entry transfer pursuant to the procedures set forth in Section 3 of the Offer to Purchase. Share Certificates for all physically delivered Shares, or a confirmation of a book-entry transfer into the Depositary's account at the Book-Entry Transfer Facility, as well as a properly completed and duly executed Letter of Transmittal (or a manually signed facsimile thereof) and any other documents required by this Letter of Transmittal, or an Agent's Message in the case of a book-entry transfer, must be received by the Depositary at one of its addresses set forth on the front page of this Letter of Transmittal by the Expiration Date (as defined in the Offer to Purchase). If Share Certificates are forwarded to the Depositary in multiple deliveries, a properly completed and duly executed Letter of Transmittal must accompany each such delivery. Stockholders whose Share Certificates are not immediately available, who cannot deliver their Share Certificates and all other required documents to the Depositary prior to the Expiration Date or who cannot complete the procedure for delivery by book-entry transfer on a timely basis, may tender their Shares pursuant to the guaranteed delivery procedure described in Section 3 of the Offer to Purchase. Pursuant to such procedure: (a) such tender must be made by or through an Eligible Institution; (b) a properly completed and duly executed Notice of Guaranteed Delivery, substantially in the form provided by the Purchaser, must be received by the Depositary on or prior to the Expiration Date; and (c) Share Certificates representing tendered Shares in proper form for tender, or a confirmation of a book-entry transfer into the Depositary's account at the Book-Entry Transfer Facility of all Shares, as well as a properly completed and duly executed Letter of Transmittal (or a manually signed facsimile thereof), and any other documents required by this Letter of Transmittal, must be received by the Depositary within three New York Stock Exchange trading days of the date of execution of such Notice of Guaranteed Delivery as provided in Section 3 of the Offer to Purchase.

THE METHOD OF DELIVERY OF THIS LETTER OF TRANSMITTAL, SHARE CERTIFICATES AND ALL OTHER REQUIRED DOCUMENTS, INCLUDING DELIVERY THROUGH ANY BOOK-ENTRY TRANSFER FACILITY, IS AT THE ELECTION AND SOLE RISK OF THE UNDERSIGNED, AND THE DELIVERY WILL BE DEEMED MADE ONLY WHEN ACTUALLY RECEIVED BY THE DEPOSITARY. IF DELIVERY IS BY MAIL, REGISTERED MAIL WITH RETURN RECEIPT REQUESTED, PROPERLY INSURED, IS RECOMMENDED. IN ALL CASES, SUFFICIENT TIME SHOULD BE ALLOWED TO ENSURE TIMELY DELIVERY.

6

        No alternative, conditional or contingent tenders will be accepted, and no fractional Shares will be purchased. By executing this Letter of Transmittal, the undersigned waives any right to receive any notice of the acceptance for payment of the Shares.

3.     ESOP.

        This Letter of Transmittal should not be used to tender any shares owned indirectly through the ESOP. Instead, participants in the ESOP should complete the Trustee Direction Form according to its instructions. However, if participants in the ESOP also own shares outside the ESOP, then such participants must complete both the Trustee Direction Form and the Letter of Transmittal if they wish to tender shares from both accounts.

4.     Inadequate Space.

        If the space provided herein is inadequate, the Share Certificate numbers, the number of Shares evidenced by such Share Certificates and the number of Shares tendered should be listed on a separate signed schedule and attached hereto.

5.     Partial Tenders (not applicable to stockholders who tender by book-entry transfer).

        If fewer than all the Shares represented by any Share Certificate delivered to the Depositary are to be tendered, fill in the number of Shares which are to be tendered in the box entitled "Number of Shares Tendered." In such case, a new certificate for the remainder of the Shares represented by the old certificate will be sent to the person(s) signing this Letter of Transmittal, unless otherwise provided in the appropriate box on this Letter of Transmittal, as promptly as practicable following the expiration or termination of the Offer. All Shares represented by certificates delivered to the Depositary will be deemed to have been tendered unless otherwise indicated.

6.     Signatures on Letter of Transmittal; Stock Powers and Endorsements.

        If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered hereby, the signature(s) must correspond with the name(s) as written on the face of the Share Certificates without alteration, enlargement or any change whatsoever.

        If any of the Shares tendered hereby are held of record by two or more persons, all such persons must sign this Letter of Transmittal.

        If any of the Shares tendered hereby are registered in names of different holders, it will be necessary to complete, sign and submit as many separate Letters of Transmittal as there are different registrations of certificates.

        If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered hereby, no endorsements of certificates or separate stock powers are required unless payment of the purchase price is to be made, or Shares not tendered or not purchased are to be returned, in the name of any person other than the registered holder(s). Signatures on any such certificates or stock powers must be guaranteed by an Eligible Institution.

        If this Letter of Transmittal is signed by a person other than the registered holder(s) of the Shares tendered hereby, certificates must be endorsed or accompanied by appropriate stock powers, in either case, signed exactly as the name(s) of the registered holder(s) appear(s) on the certificates for such Shares. Signature(s) on any such certificates or stock powers must be guaranteed by an Eligible Institution.

        If this Letter of Transmittal or any certificate or stock power is signed by a trustee, executor, administrator, guardian, attorney-in-fact, officer of a corporation or other person acting in a fiduciary

7

or representative capacity, such person should so indicate when signing, and proper evidence satisfactory to the Purchaser of the authority of such person so to act must be submitted.

7.     Stock Transfer Taxes.

        The Purchaser will pay any stock transfer taxes with respect to the sale and transfer of any Shares to it or its order pursuant to the Offer. If, however, payment of the purchase price is to be made to, or Shares not tendered or not purchased are to be returned in the name of, any person other than the registered holder(s), or if a transfer tax is imposed for any reason other than the sale or transfer of Shares to the Purchaser pursuant to the Offer, then the amount of any stock transfer taxes (whether imposed on the registered holder(s), such other person or otherwise) will be deducted from the purchase price unless satisfactory evidence of the payment of such taxes, or exemption therefrom, is submitted herewith.

Except as provided in this Instruction 7, it will not be necessary for transfer tax stamps to be affixed to the Share Certificates evidencing the Shares tendered hereby.

8.     Special Payment and Delivery Instructions.

        If the check for the purchase price of any Shares purchased is to be issued, or any Shares not tendered or not purchased are to be returned, in the name of a person other than the person(s) signing this Letter of Transmittal or if the check or any certificates for Shares not tendered or not purchased are to be mailed to someone other than the person(s) signing this Letter of Transmittal or to the person(s) signing this Letter of Transmittal at an address other than that shown above, the appropriate boxes on this Letter of Transmittal should be completed. Stockholders tendering Shares by book-entry transfer may request that Shares not purchased be credited to such account at the Book-Entry Transfer Facility as such stockholder may designate under "Special Payment Instructions." If no such instructions are given, any such Shares not purchased will be returned by crediting the account at the Book-Entry Transfer Facility designated above.

9.     Substitute Form W-9.

        Under the federal income tax laws, the Depositary will be required to withhold a portion of the amount of any payments made to certain stockholders pursuant to the Offer. In order to avoid such backup withholding, each tendering stockholder that is a United States citizen, resident or entity, and, if applicable, each other United States payee, must provide the Depositary with such stockholder's or payee's correct taxpayer identification number ("TIN") and certify that such stockholder or payee is not subject to such backup withholding by completing the attached Substitute Form W-9. Certain stockholders or payees (including, among others, corporations, non-resident foreign individuals and foreign entities) are not subject to these backup withholding and reporting requirements. For further information concerning backup withholding see "IMPORTANT TAX INFORMATION" BELOW.

        Failure to complete the Substitute Form W-9 will not, by itself, cause Shares to be deemed invalidly tendered, but may require the Depositary to withhold a portion of the amount of any payments made pursuant to the Offer. NOTE: FAILURE TO COMPLETE AND RETURN THE SUBSTITUTE FORM W-9 MAY RESULT IN BACKUP WITHHOLDING OF A PORTION OF ANY PAYMENTS MADE TO YOU PURSUANT TO THE OFFER. PLEASE REVIEW THE "IMPORTANT TAX INFORMATION" SECTION BELOW AND THE ENCLOSED "GUIDELINES FOR CERTIFICATION OF TIN ON SUBSTITUTE FORM W-9" FOR ADDITIONAL DETAILS.

10.   Mutilated, Lost, Stolen or Destroyed Certificates.

        Any holder of a certificate(s) which represented Shares whose certificate(s) has been mutilated, lost, stolen, or destroyed should (i) complete this Letter of Transmittal and check the appropriate box

8

above and (ii) contact the Company's transfer agent at (800) 851-9677. The Depositary will provide such holder with all necessary forms and instructions to replace any mutilated, lost, stolen or destroyed certificates. The holder may also be required to give the Company a bond as indemnity against any claim that may be made against it with respect to the certificate(s) alleged to have been mutilated, lost, stolen, or destroyed. However, there can be no assurances that such mutilated, lost, stolen or destroyed certificates will be replaced prior to the expiration date of the Offer.

11.   Waiver of Conditions.

        Except as otherwise provided in the Offer to Purchase, Purchaser reserves the right in its reasonable discretion to waive in whole or in part at any time or from time to time any of the specified conditions of the Offer or any defect or irregularity in tender with regard to any Shares tendered.

12.   Requests for Assistance or Additional Copies.

        Any questions and requests for assistance may be directed to the Information Agent or the Dealer Manager at the addresses and telephone numbers set forth on the back cover of this Letter of Transmittal. Additional copies of the Offer to Purchase, this Letter of Transmittal, the Notice of Guaranteed Delivery and other related materials may be obtained from the Information Agent.

IMPORTANT: THIS LETTER OF TRANSMITTAL (OR FACSIMILE HEREOF), PROPERLY COMPLETED AND DULY EXECUTED (TOGETHER WITH ANY REQUIRED SIGNATURE GUARANTEES AND SHARE CERTIFICATES OR CONFIRMATION OF BOOK-ENTRY TRANSFER AND ALL OTHER REQUIRED DOCUMENTS) OR A PROPERLY COMPLETED AND DULY EXECUTED NOTICE OF GUARANTEED DELIVERY MUST BE RECEIVED BY THE DEPOSITARY PRIOR TO THE EXPIRATION DATE (AS DEFINED IN THE OFFER TO PURCHASE).

IMPORTANT TAX INFORMATION

        Under the federal income tax law, a stockholder whose tendered Shares are accepted for payment is required by law to provide the Depositary (as payer) with such stockholder's correct TIN on Substitute Form W-9 below. If such stockholder is an individual, the TIN is such stockholder's social security number. If the Depositary is not provided with the correct TIN, the stockholder may be subject to penalties imposed by the Internal Revenue Service ("IRS") and payments that are made to such stockholder with respect to Shares purchased pursuant to the Offer may be subject to backup withholding.

        Certain stockholders (including, among others, corporations, non-resident foreign individuals and foreign entities) are not subject to these backup withholding and reporting requirements. In order for a foreign stockholder to qualify as an exempt recipient, such stockholder must submit the appropriate IRS Form W-8, signed under penalties of perjury, attesting to such individual's foreign status. Each IRS Form W-8 is available on the IRS website (www.irs.gov) or can be obtained from the Depositary.

        If backup withholding applies, the Depositary is required to withhold 28% of any payments made to the stockholder. Backup withholding is not an additional tax. Rather, the tax liability of persons subject to backup withholding will be reduced by the amount of tax withheld. If withholding results in an overpayment of taxes, a refund may be obtained from the IRS provided that the required information is furnished to the IRS.

        For further information concerning backup withholding and instructions for completing the Substitute Form W-9 (including how to obtain a TIN if you do not have one and how to complete the Substitute Form W-9 if Shares are held in more than one name), consult the enclosed "Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9."

9

Purpose of Substitute Form W-9

        To prevent backup withholding on payments that are made to a United States stockholder with respect to Shares purchased pursuant to the Offer, the stockholder is required to notify the Depositary of such stockholder's correct TIN by completing the form below certifying (i) that the TIN provided on Substitute Form W-9 is correct (or that such stockholder is awaiting a TIN) and (ii) that such stockholder is not subject to backup withholding because (a) such stockholder has not been notified by the IRS that such stockholder is subject to backup withholding as a result of a failure to report all interest or dividends, (b) the IRS has notified such stockholder that such stockholder is no longer subject to backup withholding or (c) such stockholder is exempt from backup withholding.

What Number to Give the Depositary

        United States stockholders are required to give the Depositary the social security number or employer identification number of the record holder of the Shares tendered hereby. If the Shares are in more than one name or are not in the name of the actual owner, consult the enclosed Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 for additional guidance on which number to report. If the tendering stockholder has not been issued a TIN and has applied for a number or intends to apply for a number in the near future, the stockholder should check the "Awaiting TIN" box in Part II, sign and date the Substitute Form W-9 and complete the Certificate of Awaiting Taxpayer Identification Number below. Notwithstanding that the "Awaiting TIN" box is checked in Part II and the Certificate of Awaiting Taxpayer Identification Number is completed, the Depositary will withhold 28% of all payments of the purchase price to such stockholder until a TIN is provided to the Depositary. Such amounts will be refunded to such surrendering stockholder if a TIN is provided to the Depositary within 60 days.

10

PAYOR'S NAME: The Bank of New York

SUBSTITUTE FORM W-9	Name:
	Address:
		(number and Street)
	(City)(State)(Zip Code)

Department of the	Check appropriate box:
Treasury	Individual/Sole Proprietor	o	Corporation	o	Exempt from
Internal Revenue Service	Partnership	o	Other (specify)	o	Backup Withholding	o

Request for Taxpayer	Part I—Please provide your taxpayer or identification number in the space at right. If awaiting TIN, write "Applied For."	SSN: or EIN:
Identification Number (TIN) and	Part II.—Awaiting TIN o
Certification	Part III.—Certification Under penalties of perjury, I certify that: (1)    The number shown on this form is my correct Taxpayer Identification Number (or I am waiting for a number to be issued to me); (2)    I am not subject to backup withholding either because (a) I am exempt from backup withholding, (b) I have not been notified by the IRS that I am subject to backup withholding as a result of a failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup withholding; and (3)    I am a United States person (including a United States resident alien).
	Certification Instructions — You must cross out item (2) in Part III above if you have been notified by the IRS that you are subject to backup withholding because of underreporting interest or dividends on your tax return. However, if after being notified by the IRS that you were subject to backup withholding you received notification from the IRS that you are no longer subject to backup withholding, do not cross out item (2).
Sign Here =>	Signature: Date:

NOTE: FAILURE TO COMPLETE AND RETURN THIS FORM MAY RESULT IN A $50 PENALTY IMPOSED BY THE INTERNAL REVENUE SERVICE AND BACKUP WITHHOLDING OF 28% OF ANY PAYMENTS MADE TO YOU PURSUANT TO THE OFFER. PLEASE REVIEW THE ENCLOSED GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9 FOR ADDITIONAL DETAILS.

NOTE: YOU MUST COMPLETE THE FOLLOWING CERTIFICATE IF YOU CHECKED THE BOX IN PART II OF THE SUBSTITUTE FORM W-9.

CERTIFICATION OF AWAITING TAXPAYER IDENTIFICATION NUMBER

        I certify under penalties of perjury that a taxpayer identification number has not been issued to me, and either (1) I have mailed or delivered an application to receive a taxpayer identification number to the appropriate Internal Revenue Service Center or Social Security Administration office or (2) I intend to mail or deliver an application in the near future. I understand that if I do not provide a taxpayer identification number by the time of payment, 28% of all reportable payments made to me thereafter will be withheld until I provide a taxpayer identification number to the payer and that, if I do not provide my taxpayer identification number within sixty days, such retained amounts shall be remitted to the Internal Revenue Service as backup withholding.

Signature Date

        Any questions and requests for assistance may be directed to the Information Agent or the Dealer Manager at the addresses and telephone numbers set forth below. Additional copies of the Offer to Purchase, the Letter of Transmittal and the Notice of Guaranteed Delivery may be obtained from the Information Agent at the address and telephone number set forth below. Holders of Shares may also contact their broker, dealer, commercial bank or trust company or other nominee for assistance concerning the Offer.

The Information Agent for the Offer is:
D. F. King & Co., Inc.
48 Wall Street
New York, NY 10005
(212) 269-5550
Toll-Free: (888) 628-9011
E-MAIL: info@dfking.com

The Dealer Manager for the Offer is:
Bear, Stearns & Co. Inc.
383 Madison Ave., 8th Floor
New York, NY 10179
(212) 272-5112
Toll-Free: (877) 696-BEAR

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INSTRUCTIONS FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER
IMPORTANT TAX INFORMATION
CERTIFICATION OF AWAITING TAXPAYER IDENTIFICATION NUMBER

EX-99.(A)(1)(C)

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Exhibit (a)(1)(C)

Notice of Guaranteed Delivery

to

Tender Shares of Common Stock

(including the Associated Series A Participating Preferred Stock Purchase Rights)

of

ELKCORP

to

BMCA ACQUISITION SUB INC.,

a wholly-owned subsidiary of

BMCA ACQUISTIION INC.

THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, FEBRUARY 14, 2007, UNLESS THE OFFER IS EXTENDED.

(Not be used for Signature Guarantees)

        This Notice of Guaranteed Delivery, or a form substantially equivalent to this form, must be used to accept the Offer (as defined below) (i) if certificates evidencing shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp, a Delaware corporation (the "Company"), are not immediately available, (ii) if share certificates and all other required documents cannot be delivered to The Bank of New York (the "Depositary") or (iii) if the procedure for book-entry transfer cannot be completed on a timely basis or time will not permit all required documents to reach the Depositary on or prior to the Expiration Date (as defined in the Offer to Purchase, dated January 18, 2007 (the "Offer to Purchase")). This Notice of Guaranteed Delivery may be delivered by hand or facsimile transmission or mail to the Depositary. See Section 3 of the Offer to Purchase.

The Depositary For The Offer Is:

THE BANK OF NEW YORK

By Mail:	By Overnight Courier:	By Hand:
The Bank of New York Reorganization Services P.O. Box 859208 Braintree, MA 01285-9208	The Bank of New York Reorganization Services 161 Bay State Drive Braintree, MA 02184	The Bank of New York Reorganization Services 101 Barclay Street, 1-E Receive and Deliver Window New York, NY 10286

By Facsimile Transmission:
(For Eligible Institutions Only)

(781) 380-3388

To Confirm Facsimile Only:
(781) 843-1833 Ext. 200

DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE OR TRANSMISSION OF INSTRUCTIONS VIA FACSIMILE TRANSMISSION TO A NUMBER OTHER THAN AS LISTED ABOVE DOES NOT CONSTITUTE A VALID DELIVERY TO THE DEPOSITARY.

THIS NOTICE OF GUARANTEED DELIVERY IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN "ELIGIBLE INSTITUTION" UNDER THE INSTRUCTIONS THERETO, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.

Ladies and Gentlemen:

        The undersigned hereby tenders to BMCA Acquisition Sub Inc., a Delaware corporation (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), upon the terms and subject to the conditions set forth in the Offer to Purchase, dated January 18, 2007, and the related Letter of Transmittal (which together, as amended, supplemented or otherwise modified from time to time, constitute the "Offer"), receipt of which is hereby acknowledged, the number of Shares specified below pursuant to the guaranteed delivery procedure set forth in Section 3 of the Offer to Purchase.

Number of Shares:

Certificate Nos. (if available):

Check box if Shares will be tendered by book-entry transfer: o

Account Number:

Dated: , 200

Name(s) of Record Holder(s):

(Please Print)

Address(es):

(Zip Code)

Area Code and Tel. No.:

Signature(s):

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GUARANTEE
(NOT TO BE USED FOR SIGNATURE GUARANTEES)

        The undersigned, a firm which is a bank, broker, dealer, credit union, savings association or other entity that is a participant in the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program or the Stock Exchange Medallion Program or any other "eligible guarantor institution" (as such term is defined in Rule 17Ad-15 under the Securities Exchange Act of 1934, as amended), guarantees (a) that the above named person(s) "own(s)" the Shares tendered hereby within the meaning of Rule 14e-4 under the Securities Exchange Act of 1934, (b) that such tender of Shares complies with Rule 14e-4 and (c) delivery to the Depositary of the Shares tendered hereby, in proper form of transfer, or a Book-Entry Confirmation (as defined in the Offer to Purchase), together with a properly completed and duly executed Letter of Transmittal (or a manually signed facsimile thereof) with any required signature guarantees, or an Agent's Message (as defined in the Offer to Purchase) in the case of a book-entry delivery, and any other required documents, within three New York Stock Exchange trading days after the date hereof.

        The Eligible Institution that completes this form must communicate the guarantees to the Depositary and must deliver the Letter of Transmittal and certificates for Shares to the Depositary within the time period shown herein. Failure to do so could result in a financial loss to such Eligible Institution.

Name of Firm

Address

Zip Code

Area Code and Tel. No.:

Authorized Signature

Name:

Please Print

Title

Dated: , 200

NOTE: DO NOT SEND CERTIFICATES FOR SHARES WITH THIS NOTICE. CERTIFICATES SHOULD BE SENT ONLY WITH YOUR LETTER OF TRANSMITTAL.

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GUARANTEE (NOT TO BE USED FOR SIGNATURE GUARANTEES)

EX-99.(A)(1)(D)

Exhibit (a)(1)(D)

Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(including the Associated Series A Participating Preferred Stock Purchase Rights)
of
ELKCORP
at
$42.00 NET PER SHARE
by
BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.

January 18, 2007

To Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees:

        BMCA Acquisition Sub Inc., a Delaware corporation (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), is making an offer to purchase all the outstanding shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp, a Delaware corporation (the "Company"), and the associated Series A Participating Preferred Stock purchase rights at a price of $42.00 per Share net to the seller in cash (subject to applicable withholding taxes), without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase dated January 18, 2007 (the "Offer to Purchase") and the related Letter of Transmittal (which together, as amended, supplemented or otherwise modified from time to time constitute the "Offer").

        For your information and for forwarding to your clients for whom you hold Shares registered in your name or in the name of your nominee, we are enclosing the following documents:

1.

Offer to Purchase, dated January 18, 2007;



2.

Letter of Transmittal, including a Substitute Form W-9, for your use and for the information of your clients;



3.

Notice of Guaranteed Delivery, to be used to accept the Offer if the Shares and all other required documents cannot be delivered to The Bank of New York, the Depositary for the Offer, by the expiration of the Offer;



4.

A form of letter which may be sent to your clients for whose accounts you hold Shares registered in your name or in the name of your nominee, with space provided for obtaining such clients' instructions with regard to the Offer;



5.

Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 providing information relating to backup federal income tax withholding; and



6.

Return envelope addressed to the Depositary.

        WE URGE YOU TO CONTACT YOUR CLIENTS AS PROMPTLY AS POSSIBLE.

        THE OFFER EXPIRES AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, FEBRUARY 14, 2007, UNLESS THE OFFER IS EXTENDED. SHARES TENDERED UNDER

THE OFFER MAY BE WITHDRAWN AT ANY TIME ON OR BEFORE THE EXPIRATION DATE AND, UNLESS THERETOFORE ACCEPTED FOR PAYMENT AS PROVIDED HEREIN, MAY ALSO BE WITHDRAWN AT ANY TIME AFTER MARCH 19, 2007 (OR SUCH LATER DATE AS MAY APPLY IF THE OFFER IS EXTENDED).

        The Purchaser will not pay any fees or commissions to any broker, dealer or other person (other than D. F. King & Co., Inc. (the "Information Agent"), Bear, Stearns & Co. Inc. (the "Dealer Manager"), or The Bank of New York (the "Depositary")) for soliciting tenders of Shares pursuant to the Offer. The Purchaser will, however, upon request, reimburse brokers, dealers, banks and trust companies for reasonable and necessary costs and expenses incurred by them in forwarding materials to their customers. The Purchaser will pay all stock transfer taxes applicable to its purchase of Shares pursuant to the Offer, subject to Instruction 7 of the Letter of Transmittal.

        In order to accept the Offer, a duly executed and properly completed Letter of Transmittal and any required signature guarantees, or an Agent's Message (as defined in the Offer to Purchase) in connection with a book-entry delivery of Shares, and any other required documents, must be received by the Depositary by 12:00 Midnight, New York City time, on February 14, 2007.

        Any inquiries you may have with respect to the Offer should be addressed to, and additional copies of the enclosed materials may be obtained from, the Information Agent or the Dealer Manager at the addresses and telephone numbers set forth on the back cover of the Offer to Purchase.

Very truly yours,

BMCA Acquisition Sub Inc.

NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU AS THE AGENT OF THE PURCHASER, THE INFORMATION AGENT, THE DEALER MANAGER OR THE DEPOSITARY, OR AUTHORIZE YOU OR ANY OTHER PERSON TO USE ANY DOCUMENT OR MAKE ANY STATEMENT ON BEHALF OF ANY OF THEM IN CONNECTION WITH THE OFFER OTHER THAN THE DOCUMENTS ENCLOSED HEREWITH AND THE STATEMENTS CONTAINED THEREIN.

2

EX-99.(A)(1)(E)

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Exhibit (a)(1)(E)

Offer to Purchase for Cash

All Outstanding Shares of Common Stock

(including the Associated Series A Participating Preferred Stock Purchase Rights)

of
ELKCORP
at
$42.00 NET PER SHARE
by
BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.

THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, FEBRUARY 14, 2007, UNLESS THE OFFER IS EXTENDED.

To Our Clients:

        Enclosed for your consideration are the Offer to Purchase, dated January 18, 2007 (the "Offer to Purchase"), and the related Letter of Transmittal (which together, as amended, supplemented or otherwise modified from time to time constitute the "Offer") in connection with the offer by BMCA Acquisition Sub Inc., a Delaware corporation (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), to purchase all the outstanding shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp, a Delaware corporation (the "Company"), and the associated Series A Participating Preferred Stock purchase rights (the "Rights") at a price of $42.00 per Share net to the seller in cash (subject to applicable withholding taxes), without interest thereon.

        The purpose of the Offer is for the Purchaser to acquire control of, and ultimately all the Shares of, the Company. If the Offer is consummated, the Parent intends, as soon as practicable following the consummation of the Offer, to have the Company consummate a second step merger (the "Proposed Merger") with the Purchaser pursuant to which each then outstanding Share (other than Shares already beneficially owned by BMCA) would be converted into the right to receive an amount in cash per Share equal to the highest price per Share paid by the Purchaser pursuant to the Offer, without interest.

We are the holder of record of Shares for your account. A tender of such Shares can be made only by us as the holder of record and pursuant to your instructions. The Letter of Transmittal is furnished to you for your information only and cannot be used by you to tender Shares held by us for your account.

        We request instructions as to whether you wish us to tender any or all of the Shares held by us for your account, upon the terms and subject to the conditions set forth in the Offer to Purchase and the Letter of Transmittal.

        Your attention is invited to the following:

        1.     The offer price is $42.00 per Share, net to you in cash.

        2.     The Offer is being made for all outstanding Shares.

        3.     The Offer and withdrawal rights expire at 12:00 Midnight, New York City time, on February 14, 2007, unless the Offer is extended.

        4.     The Offer is conditioned upon, among other things, there being validly tendered and not withdrawn prior to the expiration of the Offer, such number of Shares of the Company that shall constitute, when added to the Shares already beneficially owned by BMCA, a majority of the Shares outstanding, on a fully diluted basis (including, without limitation, all Shares issuable upon the exercise of any options warrants, or rights (other than the Rights)) on the date the Offer expires. The Offer is also subject to the other conditions as set forth in the Offer to Purchase. See the Introduction and Sections 11 and 14 of the Offer to Purchase.

        5.     Tendering stockholders will not be obligated to pay brokerage fees or commissions or, subject to Instruction 7 of the Letter of Transmittal, stock transfer taxes on the transfer and sale of Shares pursuant to the Offer.

        If you wish to have us tender any or all of your Shares, please so instruct us by completing, executing and returning to us the instruction form on the reverse side of this letter hereof. An envelope to return your instructions to us is enclosed. If you authorize tender of your Shares, all such Shares will be tendered unless otherwise specified on the reverse side of this letter hereof. Your instructions should be forwarded to us in ample time to permit us to submit a tender on your behalf by the expiration of the Offer.

        The Purchaser is not aware of any state in which the making of the Offer is prohibited by administrative or judicial action pursuant to any valid statute. The Offer is not being made to, nor will tenders be accepted from or on behalf of, holders of Shares in any jurisdiction in which the making of the Offer or acceptance thereof would not be in compliance with the laws of such jurisdiction.

2

Instructions with Respect to the Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(including the Associated Series A Participating Preferred Stock Purchase Rights)
of
ELKCORP
at
$42.00 NET PER SHARE
by
BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.

        The undersigned acknowledge(s) receipt of your letter, the enclosed Offer to Purchase, dated January 18, 2007, and the related Letter of Transmittal (which, as amended or supplemented from time to time, together constitute the "Offer"), in connection with the offer by BMCA Acquisition Sub Inc., a wholly-owned subsidiary of BMCA Acquisition Inc., which is a wholly-owned subsidiary of Building Materials Corporation of America, to purchase all the outstanding shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp, and the associated Series A Participating Preferred Stock purchase rights.

        This will instruct you to instruct your nominee to tender the number of Shares indicated below (or, if no number is indicated below, all Shares) that are held for the account of the undersigned, upon the terms and subject to the conditions set forth in the Offer.

NUMBER OF SHARES TO BE TENDERED*

Shares

Certificate Nos. (if available):

Account Number:

Taxpayer Identification or Social Security Number(s):

Dated: , 200

*

Unless otherwise indicated, it will be assumed that all Shares held by us for your account are to be tendered.

SIGN BELOW:

Signature(s)

Please Type or Print Name(s) Below:

Please Type or Print Address(es) Below:

Please Type or Print Area Code and Telephone Number(s):

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Offer to Purchase for Cash All Outstanding Shares of Common Stock (including the Associated Series A Participating Preferred Stock Purchase Rights)

EX-99.(A)(1)(F)

Exhibit (a)(1)(F)

Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(including the Associated Series A Participating Preferred Stock Purchase Rights)
of
ELKCORP
at
$42.00 NET PER SHARE
by
BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.

January 18, 2007

To the Participants in the ElkCorp Employee Stock Ownership Plan:

        BMCA Acquisition Sub Inc., a Delaware corporation (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), is offering to purchase all the outstanding shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp, a Delaware corporation (the "Company"), and the associated Series A Participating Preferred Stock purchase rights (the "Rights") at a price of $42.00 per Share net to the seller in cash (subject to applicable withholding taxes), without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase dated January 18, 2007 (the "Offer to Purchase") and the related Letter of Transmittal (which together, as amended, supplemented or otherwise modified from time to time constitute the "Offer").

        As a participant in the ElkCorp Employee Stock Ownership Plan (the "ESOP"), you are eligible to participate in this tender offer. A copy of the Offer to Purchase, the Letter of Transmittal, Trustee Direction Form, and other related materials are enclosed.

        The purpose of the Offer is for the Purchaser to acquire control of, and ultimately all the Shares of, the Company. If the Offer is consummated, the Parent intends, as soon as practicable following the consummation of the Offer, to have the Company consummate a second step merger (the "Proposed Merger") with the Purchaser pursuant to which each then outstanding Share (other than Shares already beneficially owned by BMCA) would be converted into the right to receive an amount in cash per Share equal to the highest price per Share paid by the Purchaser pursuant to the Offer, without interest.

        To assist with this offer, the Purchaser has engaged D. F. King & Co., Inc. to serve as the Information Agent and Bear, Stearns & Co. Inc. to serve as the Dealer Manager. Representatives from the Information Agent may contact you by phone to make sure you have received the Offer to Purchase and related materials and to answer any questions you may have. If you need information or additional forms, please call the Information Agent at (212) 269-5550 or toll-free at (888) 628-9011.

        All shares tendered and not purchased will be returned at the Purchaser's expense as soon as practicable following the expiration date.

        The Purchaser reserves the right (but will not be obligated), in its sole discretion, at any time and from time to time, to extend the period during which the Offer is open for any reason by giving oral or written notice of the extension to the Depositary (as defined in the Offer to Purchase) and by making a public announcement of the extension. During any extension, all Shares previously tendered and not withdrawn will remain subject to the Offer and subject to the right of a tendering stockholder to withdraw Shares, as described in Section 4 of the Offer to Purchase.

A TENDER OF YOUR SHARES CAN BE MADE ONLY BY THE TRUSTEE AS THE HOLDER OF RECORD AND PURSUANT TO YOUR INSTRUCTIONS. THE LETTER OF TRANSMITTAL IS FURNISHED TO YOU FOR YOUR INFORMATION ONLY AND CANNOT BE USED BY YOU TO TENDER YOUR SHARES HELD BY THE TRUSTEE FOR YOUR ACCOUNT.

Accordingly, please use the attached "Trustee Direction Form" to instruct the Delaware Charter Guarantee & Trust Company, the Trustee, as to whether you wish the Trustee to tender any or all of the Shares the Trustee holds for your account upon the terms and subject to the conditions described in the Offer to Purchase and the related Letter of Transmittal. However, if you hold Shares outside of the ESOP and wish to tender those Shares as well, then you need to complete the Letter of Transmittal according to its instructions. In either case, the Purchaser urges you to read the Offer to Purchase and Letter of Transmittal carefully before making any decision regarding the tender offer.

The Purchaser Calls Your Attention to the Following:

1.

The Offer is conditioned upon a number of conditions as set forth in the Offer to Purchase and the Letter of Transmittal.



2.

THE OFFER EXPIRES AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON FEBRUARY 14, 2007, UNLESS THE OFFER IS EXTENDED. Shares tendered under the Offer may be withdrawn at any time on or before the Expiration Date and, unless theretofore accepted for payment as provided herein, may also be withdrawn at any time after March 19, 2007 (or such later date as may apply if the Offer is extended).



3.

Tendering participants will not be obligated to pay any brokerage commissions or fees, solicitation fees, or stock transfer taxes on the purchase of Shares under the tender offer, except as set forth in the Offer to Purchase and the Letter of Transmittal.



4.

Neither the Company, the Dealer Manager, or the Depositary makes any recommendation to stockholders as to whether they should tender or refrain from tendering their Shares. Stockholders must make their own decision as to whether to tender their Shares and, if so, how many Shares to tender. In doing so, stockholders should read carefully the information in the Offer to Purchase and in the related Letter of Transmittal, including our reasons for making the offer. See the Introduction and Section 11 of the Offer to Purchase. Stockholders should discuss whether to tender their Shares with their financial or tax advisors.



5.

If you wish to have the Trustee tender any or all of your Shares, please so instruct the Trustee by completing, executing, detaching, and returning to the Trustee the attached Trustee Direction Form. If you authorize the Trustee to tender your Shares, the Delaware Charter Guarantee & Trust Company will tender all such Shares unless you specify otherwise on the attached Trustee Direction Form. In order to tender your Shares held in your ESOP account in the offer, you must return this Trustee Direction Form to the Trustee by February 9, 2007 in order for the trustee to have sufficient time to process your direction and tender your Shares.



6.

Consistent with federal law, Shares tendered by the Trustee on your behalf may not be accepted and purchased by the Purchaser if the tender offer price is less than the market price of the Company's stock on the New York Stock Exchange on the date Shares are accepted

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and purchased under this Offer. If the tender offer price is greater than or equal to the market price, then the tendered Shares will be eligible to be accepted and purchased by the Purchaser subject to the terms and conditions of the Offer. See Section 3 of the Offer to Purchase.

7.

If you fail to complete, sign, or timely transmit the Trustee Direction Form to the Trustee, you will be deemed to have instructed the Trustee not to offer any of your Shares for sale under this tender offer.

8.

The Offer is being made solely under the Offer to Purchase and the related Letter of Transmittal and is being made to all record holders of Shares. The Offer is not being made to, nor will tenders be accepted from or on behalf of, holders of Shares residing in any jurisdiction in which the making of the tender offer or acceptance thereof would not be in compliance with the securities, blue sky or other laws of such jurisdiction.

        In order to tender your Shares held in your ESOP account in the offer, you must return this Trustee Direction Form to the Trustee by February 9, 2007 in order for the Trustee to have sufficient time to process your direction and tender your Shares. The Offer will expire at 12:00 Midnight, New York City time, on February 14, 2007, unless otherwise extended.

Very truly yours,

BMCA ACQUISITION SUB INC.

3

EX-99.(A)(1)(G)

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Exhibit (a)(1)(G)

BMCA ACQUISITION SUB INC.
BMCA ACQUISITION INC.

TRUSTEE DIRECTION FORM
FOR TENDER OF
ALL OUTSTANDING SHARES OF THE COMMON STOCK OF
ELKCORP
AT A PURCHASE PRICE OF $42.00 PER SHARE
TO: THE DELAWARE CHARTER GUARANTEE & TRUST COMPANY, TRUSTEE OF THE ELKCORP EMPLOYEE STOCK OWNERSHIP PLAN

        The undersigned acknowledges receipt of the accompanying Letter to the Participants in the ElkCorp Employee Stock Ownership Plan (the "ESOP"), the enclosed Offer to Purchase, dated January 18, 2006 (the "Offer to Purchase"), and the Letter of Transmittal in connection with the offer by BMCA Acquisition Sub Inc., a Delaware corporation (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), to purchase all the outstanding shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp, a Delaware corporation (the "Company"), and the associated Series A Participating Preferred Stock purchase rights at a price of $42.00 per Share net to the seller in cash (together with the Offer to Purchase, the "Offer").

        Furthermore, the undersigned has read and understands the Letter to the Participants in the ESOP, the Offer to Purchase, and the Letter of Transmittal and hereby agrees to be bound by the terms and conditions of the Offer.

        Consistent with federal law, Shares tendered by the Trustee on behalf of the undersigned may not be accepted and purchased by the Purchaser if the tender offer price is less than the market price of the Company's stock on the New York Stock Exchange on the date Shares are accepted and purchased under this Offer. If the tender offer price is greater than or equal to the market price, then the tendered Shares will be eligible to be accepted and purchased by the Purchaser subject to the terms and conditions of the Offer. See Section 3 of the Offer to Purchase.

        These instructions will direct the Delaware Charter Guarantee & Trust Company, as Trustee for the ESOP (the "Trustee"), to tender Shares held by the Trustee for the undersigned's ESOP account upon the terms and subject to the conditions set forth in the Offer to Purchase.

SHARES ALLOCATED TO PARTICIPANT'S ESOP ACCOUNTS FOR WHICH THE TRUSTEE DOES NOT RECEIVE DIRECTIONS WILL NOT BE TENDERED.

NUMBER OF SHARES TENDERED

(CHECK ONE BOX)

o

I direct the Trustee to tender ALL of the Shares in my ESOP.

o

I direct the Trustee to tender                          Shares in my ESOP account.

In order to tender the Shares held in the undersigned's ESOP account in the Offer, the undersigned must return this Trustee Direction Form to the Trustee by February 9, 2007 in order for the Trustee to have sufficient time to process the undersigned's direction and tender the undersigned's Shares. The Offer will expire at 12:00 Midnight, New York City time, on February 14, 2007.

The method of delivery of this document is at the election and risk of the ESOP participant. If delivery is by mail, then registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

THE ADDRESS TO MAIL THIS FORM TO IS:

Delaware Charter Guarantee & Trust Company
1013 Centre Road
Wilmington, DE 19805-0000

        Neither the Company, Bear, Stearns & Co. Inc. (the "Dealer Manager"), or The Bank of New York (the "Depositary") makes any recommendation to stockholders as to whether they should tender or refrain from tendering their Shares. Stockholders must make their own decision as to whether to tender their Shares and, if so, how many Shares to tender. In doing so, stockholders should read carefully the information in the Offer to Purchase and in the related Letter of Transmittal, including the Purchaser's reasons for making the offer. See the Introduction and Section 11 of the Offer to Purchase. Stockholders should discuss whether to tender their Shares with their financial or tax advisors.

Signatures:

Name(s) of Record Holder(s):
	(Please Type or Print)

Social Security or Taxpayer ID Number:

Address:

(Street) (City) (State) (Zip Code)

Daytime Area Code and Telephone No.:

Date:

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NUMBER OF SHARES TENDERED

EX-99.(A)(A)(H)

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Exhibit (a)(1)(H)

GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
NUMBER ON SUBSTITUTE FORM W-9

GUIDELINES FOR DETERMINING THE PROPER IDENTIFICATION NUMBER TO GIVE THE PAYER.—Social Security Numbers have nine digits separated by two hyphens: i.e., 000-00-0000. Employer Identification Numbers have nine digits separated by only one hyphen: i.e., 00-0000000. The table below will help determine the number to give the payer.

FOR THIS TYPE OF ACCOUNT:			GIVE THE SOCIAL SECURITY NUMBER OF:
1.	An individual's account		The individual
2.	Two or more individuals (joint account)		The actual owner of the account or, if combined funds, any one of the individuals(1)
3.	Husband and wife (joint account)		The actual owner of the account or, if joint funds, either person(1)
4.	Custodian account of a minor (Uniform Gift to Minors Act)		The minor(2)
5.	Adult and minor (joint account)		The adult or, if the minor is the only contributor, the minor(1)
6.	Account in the name of guardian or committee for a designated ward, minor, or incompetent person		The ward, minor, or incompetent person(3)
7.	a.	The usual revocable savings trust account (grantor is also trustee)	The grantor-trustee(1)
	b.	So-called trust account that is not a legal or valid trust under State law	The actual owner(1)

FOR THIS TYPE OF ACCOUNT:		GIVE THE EMPLOYER IDENTIFICATION NUMBER OF:
8.	Sole proprietorship account	The Owner(4)
9.	A valid trust, estate or pension trust	The legal entity (Do not furnish the identifying number of the personal representative or trustee unless the legal entity itself is not designated in the account title)(5)
10.	Corporate account	The corporation
11.	Religious, charitable, or educational organization account	The organization
12.	Partnership account held in the name of the business	The partnership
13.	Association, club, or other tax-exempt organization	The organization
14.	A broker or registered nominee	The broker or nominee
15.	Account with the Department of Agriculture in the name of a public entity (such as a State or local government, school district, or prison) that receives agricultural program payments	The public entity

(1)

List first and circle the name of the person whose number you furnish.

(2)

Circle the minor's name and furnish the minor's social security number.

(3)

Circle the ward's, minor's or incompetent person's name and furnish such person's social security number.

(4)

You must show your individual name, but you may also enter your business or "doing business" name. You may use either your Social Security Number or Employer Identification Number.

(5)

List first and circle the name of the legal trust, estate, or pension trust.

NOTE:    If no name is circled when there is more than one name, the number will be considered to be that of the first name listed.

OBTAINING A NUMBER

If you do not have a taxpayer identification number or if you do not know your number, obtain Form SS-5, Application for Social Security Number Card, or Form SS-4, Application for Employer Identification Number, at the local office of the Social Security Administration or the Internal Revenue Service (the "IRS") and apply for a number.

Payees generally exempt from backup withholding on payments by brokers include the following:

•

A corporation.



•

A financial institution.



•

An organization exempt from a tax under Section 501(a) or an individual retirement plan or a custodial account under Section 403(b)(7) if the account satisfies the requirements of Section 401(F)(2).



•

The United States or any agency or instrumentality thereof.



•

A State, the District of Columbia, a possession of the United States or any subdivision or instrumentality thereof.



•

A foreign government, a political subdivision of a foreign government or any agency or instrumentality thereof.



•

An international organization or any agency or instrumentality thereof.



•

A registered dealer in securities or commodities registered in the U.S. or a possession of the U.S.



•

A real estate investment trust.



•

A common trust fund operated by a bank under Section 584(a).



•

An entity registered at all times under the Investment Company Act of 1940.



•

A foreign central bank of issue.



•

A futures commission merchant registered with the Commodity Futures Trading Commission.



•

A person registered under the Investment Advisors Act of 1940 who regularly acts as a broker.

Payments of dividends and patronage dividends not generally subject to backup withholding include the following:

•

Payments to nonresident aliens subject to withholding under Section 1441.



•

Payments to partnerships not engaged in a trade or business in the U.S. and which have at least one nonresident partner.



•

Payments of patronage dividends where the amount received is not paid in money.



•

Payments made by certain foreign organizations.



•

Payments made to a nominee.

Payments of interest not generally subject to backup withholding include the following:

•

Payments of interest on obligations issued by individuals. Note: You may be subject to backup withholding if this interest is $600 or more and is paid in the course of the payer's trade or business and you have not provided your correct taxpayer identification number to the payer.



•

Payments of tax-exempt interest (including exempt-interest dividends under Section 852).

2

•

Payments described in Section 6049(b)(5) to nonresident aliens.



•

Payments on tax-free covenant bonds under Section 1451.



•

Payments made by certain foreign corporations.



•

Payments made to a nominee.

Exempt payees described above should provide an IRS Form W-9 or the Substitute Form W-9 to avoid possible erroneous backup withholding. PROVIDE THIS FORM TO THE PAYER, FURNISH YOUR TAXPAYER IDENTIFICATION NUMBER, CHECK THE "EXEMPT FROM BACKUP WITHHOLDING" BOX ON THE FORM, SIGN AND DATE THE FORM AND RETURN IT TO THE PAYER.

Certain payments other than interest, dividends and patronage dividends, which are not subject to information reporting are also not subject to backup withholding. For details, see the regulations under Section 6041, 6041(A)(a), 6045, and 6050A.

PRIVACY ACT NOTICE.—Section 6109 requires most recipients of dividend, interest or other payments to give taxpayer identification numbers to payers who must report the payments to IRS. IRS uses the numbers for identification purposes. Payers must be given the numbers whether or not recipients are required to file tax returns. Beginning January 1, 1993, payers must generally withhold a portion of taxable interest, dividend and certain other payments to a payee who does not furnish a taxpayer identification number to a payer. Certain penalties may also apply.

PENALTIES

(1)

PENALTY FOR FAILURE TO FURNISH TAXPAYER IDENTIFICATION NUMBER.—If you fail to furnish your taxpayer identification number to a payer, you are subject to a penalty of $50 for each such failure unless your failure is due to reasonable cause and not to willful neglect.

(2)

CIVIL PENALTY FOR FALSE INFORMATION WITH RESPECT TO WITHHOLDING.—If you make a false statement with no reasonable basis which results in no imposition of backup withholding, you are subject to a penalty of $500.

(3)

CRIMINAL PENALTY FOR FALSIFYING INFORMATION.—Willfully falsifying certifications or affirmations may subject you to criminal penalties including fines and/or imprisonment.

FOR ADDITIONAL INFORMATION CONTACT YOUR TAX CONSULTANT OR THE INTERNAL REVENUE SERVICE.

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GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9

EX-99.(A)(1)(I)

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Exhibit (a)(1)(I)

        FOR IMMEDIATE RELEASE

For more information, contact Building Materials Corporation of America at 973-317-5960

BMCA ANNOUNCES TENDER OFFER TO PURCHASE ALL OUTSTANDING SHARES OF COMMON STOCK OF ELKCORP AT $42.00 PER SHARE

        January 18, 2007—Building Materials Corporation of America ("BMCA"), North America's largest roofing manufacturer, which operates under the name GAF Materials Corporation, announced that BMCA Acquisition Sub Inc., an indirect wholly-owned subsidiary of BMCA, today commenced a tender offer to purchase all the outstanding shares of common stock of ElkCorp, par value $1.00 per share, at a price of $42.00 per share cash consideration. The tender offer is scheduled to expire at 12:00 Midnight, New York City time, on February 14, 2007. BMCA today withdrew and terminated its $40.00 per share tender offer, dated December 20, 2006, as today's offer supersedes it.

        In a letter from Robert B. Tafaro, BMCA's President and Chief Executive Officer to the Special Committee of the Board of Directors of ElkCorp, Mr. Tafaro stated: "Based upon BMCA's increased tender offer price, our offer is clearly superior to Carlyle's revised offer, and we urge that the due diligence process be resumed so as to enable BMCA to eliminate certain tender offer conditions, as BMCA and Elk had already agreed subject to satisfactory completion of due diligence. We are absolutely committed to this transaction and stand ready to conclude a mutually agreeable negotiated transaction at the earliest possible time."

        The tender offer materials are also being filed today with the SEC. The complete terms and conditions of the offer are set forth in the Offer to Purchase, copies of which can be obtained by contacting the information agent, D.F. King & Co., Inc. at (888) 628-9011. Bear, Stearns & Co. Inc. is acting as the dealer manager and The Bank of New York is acting as the depositary. Willkie Farr & Gallagher LLP is acting as legal advisor to BMCA, BMCA Acquisition Inc. and BMCA Acquisition Sub Inc.

        BMCA's letter to the Special Committee of the Board of Directors of ElkCorp reads as follows:

        January 18, 2007

Special Committee of the Board of Directors of ElkCorp
c/o Mark Gordon, Esq.
Wachtell Lipton Rosen & Katz
51 West 52nd Street
New York, NY 10019

        Ladies and Gentlemen:

        This is to advise you that BMCA, through its acquisition subsidiary, has raised its tender offer price this morning from $40 to $42 per share cash consideration for all Elk shares, effectively superseding BMCA's previous tender offer. In addition, J.P. Morgan Securities has joined our bank

consortium with Deutsche Bank and Bear Stearns, and we have financing commitments, in the form you requested, sufficient to fund the full price of the transaction.

        We were again disappointed by your announcement on Tuesday that you have entered into a revised merger transaction with Carlyle, with Elk's CEO to be a partner in the buyout group, without notice to BMCA affording it the opportunity to increase its bid. As you know, we were, until the Tuesday announcement, making substantial progress toward a mutually acceptable merger agreement, had received revised financing commitments in the form you requested, and performed due diligence. In the latter connection, as a result of the hard work of my BMCA colleagues and their Elk counterparts, working sometimes around the clock over the past two weeks, we have managed to finish a substantial portion of the same due diligence that Carlyle had been working on for some months.

        We believe that the action taken by Elk on Tuesday represents an attempt to prematurely terminate the auction process. At the same time, Elk unilaterally terminated the due diligence process. The fact that we are in a competitive situation only underscores our need for the balance of the due diligence information so that we can participate on a level playing field and have the opportunity to maximize value for Elk shareholders.

        Based upon BMCA's increased tender offer price, our offer is clearly superior to Carlyle's revised offer, and we urge that the due diligence process be resumed so as to enable BMCA to eliminate certain tender offer conditions, as BMCA and Elk had already agreed subject to satisfactory completion of due diligence. We are highly committed to this transaction and stand ready to conclude a mutually agreeable negotiated transaction at the earliest possible time.

        Sincerely,

        /s/ Robert B. Tafaro

Robert B. Tafaro
President and Chief Executive Officer

cc: Mr. Thomas D. Karol, CEO
      Mr. Lee Lebrun, UBS

# # #

BMCA INFORMATION

        Building Materials Corporation of America, which operates under the name of GAF Materials Corporation, is an indirect subsidiary of G-I Holdings Inc. With annual sales in 2005 approximating $2.0 billion, BMCA is North America's largest manufacturer of residential and commercial roofing products and specialty building products.

# # #

        THIS PRESS RELEASE IS FOR INFORMATIONAL PURPOSES ONLY AND DOES NOT CONSTITUTE AN OFFER TO BUY OR THE SOLICITATION OF AN OFFER TO SELL SHARES OF ELKCORP COMMON STOCK. THE TENDER OFFER IS BEING MADE ONLY PURSUANT TO THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS THAT BMCA ACQUISITION SUB INC. WILL SHORTLY BE DISTRIBUTING TO ELKCORP'S STOCKHOLDERS AND HAS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION. STOCKHOLDERS SHOULD READ CAREFULLY THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS BECAUSE THEY CONTAIN IMPORTANT INFORMATION, INCLUDING THE VARIOUS TERMS OF, AND CONDITIONS TO, THE TENDER OFFER. STOCKHOLDERS MAY OBTAIN A FREE COPY OF THE TENDER OFFER STATEMENT ON SCHEDULE TO, THE OFFER TO PURCHASE, LETTER OF

2

TRANSMITTAL AND OTHER DOCUMENTS THAT BMCA ACQUISITION SUB INC. HAS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION AT THE COMMISSION'S WEBSITE AT WWW.SEC.GOV. STOCKHOLDERS ARE URGED TO CAREFULLY READ THESE MATERIALS PRIOR TO MAKING ANY DECISION WITH RESPECT TO THE TENDER OFFER.

# # #

FORWARD-LOOKING STATEMENTS

This release contains some forward-looking statements as defined by the federal securities laws which are based on our current expectations and assumptions, which are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated, projected or implied. We undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.

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BMCA ANNOUNCES TENDER OFFER TO PURCHASE ALL OUTSTANDING SHARES OF COMMON STOCK OF ELKCORP AT $42.00 PER SHARE

EX-99.(A)(1)(J)

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Exhibit (a)(1)(J)

This announcement is neither an offer to purchase nor a solicitation of an offer to sell Shares (as defined below). The Offer (as defined below) is made solely by the Offer to Purchase, dated January 18, 2007, and the related Letter of Transmittal, and is being made to all holders of Shares. The Offer is not being made to (nor will tenders be accepted from or on behalf of) holders of Shares in any jurisdiction in which the making of the Offer or the acceptance thereof would not be in compliance with the laws of such jurisdiction. In those jurisdictions where the applicable laws require that the Offer be made by a licensed broker or dealer, the Offer shall be deemed to be made on behalf of BMCA Acquisition Sub Inc. by Bear, Stearns & Co. Inc., the Dealer Manager or one or more registered brokers or dealers licensed under the laws of such jurisdiction.

Notice of Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(including the Associated Series A Participating
Preferred Stock Purchase Rights)
of
ELKCORP
at
$42.00 Net Per Share
by
BMCA ACQUISITION SUB INC.,
a wholly-owned subsidiary of
BMCA ACQUISITION INC.

        BMCA Acquisition Sub Inc., a Delaware corporation (including any successor thereto, the "Purchaser"), a wholly-owned subsidiary of BMCA Acquisition Inc. (the "Parent"), which is a wholly-owned subsidiary of Building Materials Corporation of America ("BMCA"), is offering to purchase all the outstanding shares of common stock, par value $1.00 per share (the "Shares"), of ElkCorp, a Delaware corporation (the "Company"), and the associated Series A Participating Preferred Stock purchase rights (the "Rights") at a price of $42.00 per share net to the seller in cash (subject to applicable withholding taxes), without interest thereon (the "Offer Price"), upon the terms and subject to the conditions set forth in the Offer to Purchase dated January 18, 2007 (the "Offer to Purchase"), and in the related Letter of Transmittal (which, together with any amendments and supplements thereto, collectively constitute the "Offer"). The Purchaser is offering to acquire all of the Shares as a first step in acquiring the entire equity interest in and thus control of the Company. Following the purchase of the Shares in the Offer, the Parent intends to have the Company consummate a second step merger with the Purchaser as described below to acquire all of the outstanding shares of the Company common stock that are not tendered to and accepted for payment by the Purchaser in the Offer.

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, FEBRUARY 14, 2007 UNLESS THE OFFER IS EXTENDED (THE "EXPIRATION DATE").

        The Offer is conditioned upon, among other things, there being validly tendered and not withdrawn prior to the expiration of the Offer, a number of Shares that, when added to the Shares already beneficially owned by the BMCA, shall constitute a majority of the Shares outstanding on a fully diluted basis on the Expiration Date.

        The purpose of the Offer is to acquire control of, and the entire equity interest in, the Company. If the Offer is consummated, the Parent intends, as soon as practicable following the consummation of the Offer, to have the Company consummate a second step merger (the "Proposed Merger") with the

Purchaser pursuant to which each then outstanding Share (other than Shares already beneficially owned by BMCA) would be converted into the right to receive an amount in cash per Share equal to the highest price per Share paid by the Purchaser pursuant to the Offer, without interest.

        For purposes of the Offer, the Purchaser will be deemed to have accepted for payment, and thereby purchased, Shares validly tendered and not withdrawn as, if and when the Purchaser gives oral or written notice to The Bank of New York, as depositary (the "Depositary"), of the Purchaser's acceptance of such Shares for payment pursuant to the Offer. In all cases, upon the terms and subject to the conditions of the Offer, payment for Shares purchased pursuant to the Offer will be made by deposit of the purchase price therefor with the Depositary, which will act as agent for tendering stockholders for the purpose of receiving payment from Purchaser and transmitting payment to validly tendering stockholders. In all cases, payment for Shares purchased pursuant to the Offer will be made only after timely receipt by the Depositary of (i) share certificates representing such Shares or a timely Book Entry Confirmation (as defined in the Offer to Purchase) with respect thereto, (ii) the Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, with any required signature guarantees or an Agent's Message (as defined in the Offer to Purchase) in connection with a book-entry transfer and (iii) any other documents required by the Letter of Transmittal. The per share consideration paid to any holder of Shares pursuant to the Offer will be the highest per share consideration paid to any other holder of such Shares pursuant to the Offer. Holders of Shares through the Employee Stock Ownership Plan (the "ESOP") will need to timely deliver a Trustee Instruction Letter. Under no circumstances will interest on the purchase price for Shares be paid by the Purchaser, regardless of any extension of the Offer or any delay in making such payment.

        The Purchaser expressly reserves the right, in its sole discretion, at any time and from time to time, to extend the period during which the Offer is open for any reason, by giving oral or written notice of such extension to the Depositary. Any such extension will be followed as promptly as practicable by public announcement thereof, and such announcement will be made no later than 9:00 a.m., New York City time, on the next business day after the previously scheduled Expiration Date.

        Tenders of Shares made pursuant to the Offer are irrevocable, except that Shares tendered pursuant to the Offer may be withdrawn at any time on or prior to the Expiration Date and, unless theretofore accepted for payment as provided in the Offer to Purchase, may also be withdrawn at any time after March 19, 2007 (or such later date as may apply if the Offer is extended). In order for a withdrawal to be effective, a notice of withdrawal must be timely received by the Depositary at one of its addresses set forth on the back cover of the Offer to Purchase. Any such notice of withdrawal must specify the name of the person who tendered the Shares to be withdrawn, the number of Shares to be withdrawn and the name of the registered holder of the Shares to be withdrawn, if different from the name of the person who tendered the Shares. If share certificates evidencing Shares to be withdrawn have been delivered or otherwise identified to the Depositary, then, prior to the physical release of such certificates, the serial numbers shown on such certificates must be submitted to the Depositary and, unless such Shares have been tendered by a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a participant in the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program or the Stock Exchange Medallion Program (an "Eligible Institution"), the signatures on the notice of withdrawal must be guaranteed by an Eligible Institution. If Shares have been delivered pursuant to the book-entry transfer procedures as set forth in Section 3 of the Offer to Purchase, any notice of withdrawal must also specify the name and number of the account at the Book-Entry Transfer Facility to be credited with the withdrawn Shares and otherwise comply with the Book-Entry Transfer Facility's procedures. All questions as to the form and validity (including time of receipt) of notices of withdrawal will be determined by Purchaser, in its sole discretion, whose determination shall be final and binding. Any Shares properly withdrawn will be deemed not validly tendered for purposes of the Offer, but may be retendered at any subsequent time prior to the expiration of the Offer by following any of the procedures described in Section 3 of the Offer to Purchase.

        Participants in the ElkCorp ESOP who wish to withdraw their Shares must submit a new Trustee Direction Form indicating the withdrawal. However, the new Trustee Direction Form will only be

effective if it is received by the Trustee (as defined in the Trustee Direction Form) of the ESOP by 12:00 Midnight, New York City time, Friday, February 9, 2007, three business days before the expiration of the Offer on February 14, 2007. Upon timely receipt of the new Trustee Direction Form, the old instructions will be deemed canceled. If such participants wish to later re-tender their Shares under the ESOP, then another, new Trustee Direction Form must be received by the Trustee by 12:00 Midnight., New York City time, three business days before the expiration of the Offer.

        The information required to be disclosed by Rule 14d-6 of the General Rules and Regulations under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), is contained in the Offer to Purchase, and is incorporated herein by reference.

        A request has been made to the Company under Rule 14d-5 of the Exchange Act and under Section 220(b) of the Delaware General Corporation Law for use of the Company's stockholder lists and security position listings for the purpose of disseminating the Offer to stockholders. Upon compliance by the Company with this request and receipt of these lists or listings from the Company, the Offer to Purchase, the Letter of Transmittal and all other relevant materials will be mailed to record holders of Shares and will be furnished to brokers, dealers, banks, trust companies and similar persons whose names, or the names of whose nominees, appear on the Company's stockholders lists, or, if applicable, who are listed as participants in a clearing agency's security position listing for subsequent transmittal to beneficial owners of Shares by the Purchaser. Alternatively if the Company so elects, the materials will be mailed to stockholders by the Company.

The Offer to Purchase and the related Letter of Transmittal contain important information which should be read carefully before any decision is made with respect to the Offer. Participants in the ESOP should read the Trustee Direction Form and the Letter to Participants in the ESOP, as well as the Offer to Purchase and the related Letter of Transmittal, before any decision is made with respect to the Offer.

        Any questions or requests for assistance may be directed to the Information Agent or the Dealer Manager at their respective telephone numbers listed below. Additional copies of the Offer to Purchase, the Letter of Transmittal and other tender offer materials may be obtained from the Information Agent as set forth below, and will be furnished promptly at the Purchaser's expense. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance, concerning the Offer.

The Information Agent for the Offer is:

D. F. King & Co., Inc.
48 Wall Street
New York, NY 10005
(212) 269-5550
Toll Free: (888) 628-9011
E-MAIL: info@dfking.com

The Dealer Manager for the Offer is:

Bear, Stearns & Co. Inc.
383 Madison Avenue
New York, NY 10179
(212) 272-5112
Toll-Free: (877) 696-BEAR

January 18, 2007

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Notice of Offer to Purchase for Cash All Outstanding Shares of Common Stock (including the Associated Series A Participating Preferred Stock Purchase Rights) of ELKCORP at $42.00 Net Per Share by BMCA ACQUISITION SUB INC., a wholly-owned subsidiary of BMCA ACQUISITION INC.

EX-99.(A)(1)(K)

Exhibit (a)(1)(K)

[Letterhead of Heyman Properties]

Samuel J. Heyman
Chief Executive Officer

CONFIDENTIAL

August 28, 2006

Mr. Robert Tafaro
BMCA
1361 Alps Road
Wayne, NJ 07470

Dear Bob:

        BMCA currently has under consideration a proposed possible merger with a building materials company, which as you know will require a refinancing of BMCA's credit agreement. In that regard, as a result of current BMCA credit agreement restrictions, this is to confirm that you have asked me to facilitate such possible acquisition by purchasing that company's shares in the open market. I have agreed to do so, through myself and affiliate entities. In the event that BMCA should be permitted, by its credit agreement in connection with the above refinancing, to purchase such shares, I have agreed, if BMCA so requests, to sell them to BMCA at cost.

Sincerely,

/s/ Samuel J. Heyman

SJH:kjc

EX-99.(A)(1)(L)

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Exhibit (a)(1)(L)

[LETTERHEAD]

FOR IMMEDIATE RELEASE

For more information, contact Building Materials Corporation of America at 973-317-5960

BMCA ANNOUNCES COMMENCEMENT OF ITS TENDER OFFER TO ACQUIRE ELKCORP

        December 17, 2006—Building Materials Corporation of America ("BMCA"), North America's largest roofing manufacturer, which operates under the name GAF Materials Corporation, today announced its intention to commence a tender offer to purchase all the outstanding shares of common stock of ElkCorp, par value $1.00 per share, at a price of $35.00 per share.

        The following are the principal terms of BMCA's offer:

Price:    BMCA, through an acquisition subsidiary, proposes to acquire ElkCorp through an all cash transaction at a price of $35.00 per share of ElkCorp common stock. The proposed price of $35.00 per share represents an approximate 40% premium over ElkCorp's closing price on November 3, 2006 ($25.18 per share), the trading day immediately preceding BMCA's filing of its Schedule 13D and ElkCorp's announcement of its sale process.

Regulatory:    As previously announced, the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act expired on December 6, 2006.

        Counsel to BMCA for the tender offer is Willkie Farr & Gallagher LLP.

        The Offer to Purchase, Letter of Transmittal and related documents will be mailed to stockholders of record when available and also will be made available for distribution to beneficial owners of ElkCorp's common stock.

        In connection with its announcement of the tender offer, BMCA today sent the following letter to Thomas D. Karol, Chairman of the Board of Directors and Chief Executive Officer of ElkCorp:

        December 17, 2006

Mr. Thomas D. Karol
Chairman of the Board and CEO
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

Dear Tom:

        We are today announcing that we will be commencing a tender offer for all outstanding Elk common shares at $35 per share. As you know, we have already received antitrust clearance and this offer is not conditional on financing.

        Tom, BMCA has been both open and direct in all its dealings with you, your colleagues, and outside advisors. Notwithstanding, Elk has refused to enter into discussions with us regarding our merger proposal or provide confidential information as it has with other bidders. Most recently, on Tuesday, December 12^th, our representatives contacted your financial advisors, UBS, seeking guidance on how best to proceed. UBS informed us that BMCA's merger proposal was scheduled to be considered at an Elk Board meeting on December 13^th and that they would be in a position to provide us with guidance in a call immediately after the meeting. Instead, we have heard nothing from your advisors, and they have since "gone off the air."

        You should know that, in light of the above, you have given us no choice but to take our offer directly to shareholders. Please be assured that we continue to stand ready to negotiate a definitive merger agreement directly with Elk, if it so chooses, and we believe this to be in the best interests of Elk, its shareholders and employees.

        All the best.

Sincerely,

/s/ Robert B. Tafaro Robert B. Tafaro
President and Chief Executive Officer

cc: Elk Board of Directors

2

# # #

BMCA INFORMATION

        Building Materials Corporation of America, which operates under the name of GAF Materials Corporation, is an indirect subsidiary of G-I Holdings Inc. With annual sales in 2005 approximating $2.0 billion, BMCA is North America's largest manufacturer of residential and commercial roofing products and specialty building products.

# # #

        THIS PRESS RELEASE IS FOR INFORMATIONAL PURPOSES ONLY AND DOES NOT CONSTITUTE AN OFFER TO BUY OR THE SOLICITATION OF AN OFFER TO SELL SHARES OF ELKCORP COMMON STOCK. THE TENDER OFFER IS BEING MADE ONLY PURSUANT TO THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS THAT BMCA WILL SHORTLY BE DISTRIBUTING TO ELKCORP'S STOCKHOLDERS AND FILING WITH THE SECURITIES AND EXCHANGE COMMISSION. STOCKHOLDERS SHOULD READ CAREFULLY THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS BECAUSE THEY CONTAIN IMPORTANT INFORMATION, INCLUDING THE VARIOUS TERMS OF, AND CONDITIONS TO, THE TENDER OFFER. STOCKHOLDERS MAY OBTAIN A FREE COPY OF THE TENDER OFFER STATEMENT ON SCHEDULE TO, THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND OTHER DOCUMENTS THAT BMCA WILL SHORTLY BE FILING WITH THE SECURITIES AND EXCHANGE COMMISSION AT THE COMMISSION'S WEBSITE AT WWW.SEC.GOV. STOCKHOLDERS ARE URGED TO CAREFULLY READ THESE MATERIALS PRIOR TO MAKING ANY DECISION WITH RESPECT TO THE TENDER OFFER.

# # #

FORWARD-LOOKING STATEMENTS

This release contains some forward-looking statements as defined by the federal securities laws which are based on our current expectations and assumptions, which are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated, projected or implied. We undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.

3

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[LETTERHEAD]
BMCA ANNOUNCES COMMENCEMENT OF ITS TENDER OFFER TO ACQUIRE ELKCORP

EX-99.(A)(1)(M)

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Exhibit (a)(1)(M)

[LETTERHEAD]

December 17, 2006

Mr. Thomas D. Karol
Chairman of the Board and CEO
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

Dear Tom:

        We are today announcing that we will be commencing a tender offer for all outstanding Elk common shares at $35 per share. As you know, we have already received antitrust clearance and this offer is not conditional on financing.

        Tom, BMCA has been both open and direct in all its dealings with you, your colleagues, and outside advisors. Notwithstanding, Elk has refused to enter into discussions with us regarding our merger proposal or provide confidential information as it has with other bidders. Most recently, on Tuesday, December 12^th, our representatives contacted your financial advisors, UBS, seeking guidance on how best to proceed. UBS informed us that BMCA's merger proposal was scheduled to be considered at an Elk Board meeting on December 13^th and that they would be in a position to provide us with guidance in a call immediately after the meeting. Instead, we have heard nothing from your advisors, and they have since "gone off the air."

        You should know that, in light of the above, you have given us no choice but to take our offer directly to shareholders. Please be assured that we continue to stand ready to negotiate a definitive merger agreement directly with Elk, if it so chooses, and we believe this to be in the best interests of Elk, its shareholders and employees.

        All the best.

Sincerely,

/s/ Robert B. Tafaro Robert B. Tafaro
President and Chief Executive Officer

cc: Elk Board of Directors

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[LETTERHEAD]

EX-99.(A)(1)(N)

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Exhibit (a)(1)(N)

[Letterhead of BMCA]

FOR IMMEDIATE RELEASE

For more information, contact Building Materials Corporation of America at 973-317-5960

BMCA ANNOUNCES COMMENCEMENT OF ITS TENDER OFFER TO ACQUIRE
ELKCORP FOR $40 PER SHARE CASH CONSIDERATION

December 18, 2006—Building Materials Corporation of America ("BMCA"), North America's largest roofing manufacturer, which operates under the name GAF Materials Corporation, today announced its intention to increase the price of its tender offer to purchase all the outstanding shares of common stock of ElkCorp from $35 per share previously announced to a price of $40 per share cash consideration. In connection with the announcement, BMCA sent the following letter to the ElkCorp Board of Directors:

December 18, 2006

Board of Directors
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

Ladies and Gentlemen:

        This is to advise you that BMCA is raising its tender offer price from $35 to $40 per share cash consideration for all Elk shares.

        We were surprised and disappointed by your announcement today that you have agreed to a leveraged buyout for Elk involving management participation, as this was done without once contacting us regarding our proposal to buy Elk or providing an opportunity for BMCA to bid. As you know, BMCA advised Elk more than four weeks ago, on November 15th, that BMCA was in a position to consider increasing its $35 per share price. Finally, instead of encouraging BMCA to maximize the value of its offer, to add insult to injury, your advisors attempted, in a 3:49 AM email on Monday morning, to persuade us to defer making the tender offer to your shareholders that we had informed you about on Sunday night. How could these actions possibly be in the interests of Elk shareholders?

        While you have not communicated the details of your leveraged buyout, we trust that you have not agreed to anything that would prevent us from competing economically and in effect preclude a higher offer for your shareholders. Finally, our offer is obviously superior to the Elk leveraged buyout in both price and the fact that BMCA's offer is a tender offer, not subject to regulatory clearance, and, barring any undue delay on the part of Elk, should close in January 2007.

        Please advise us how you wish to proceed.

        All the best.

Sincerely,

/s/  ROBERT B. TAFARO

Robert B. Tafaro
President and Chief Executive Officer

# # #

BMCA INFORMATION
Building Materials Corporation of America, which operates under the name of GAF Materials Corporation, is an indirect subsidiary of G-I Holdings Inc. With annual sales in 2005 approximating $2.0 billion, BMCA is North America's largest manufacturer of residential and commercial roofing products and specialty building products.

# # #

THIS PRESS RELEASE IS FOR INFORMATIONAL PURPOSES ONLY AND DOES NOT CONSTITUTE AN OFFER TO BUY OR THE SOLICITATION OF AN OFFER TO SELL SHARES OF ELKCORP COMMON STOCK. THE TENDER OFFER IS BEING MADE ONLY PURSUANT TO THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS THAT BMCA WILL SHORTLY BE DISTRIBUTING TO ELKCORP'S STOCKHOLDERS AND FILING WITH THE SECURITIES AND EXCHANGE COMMISSION. STOCKHOLDERS SHOULD READ CAREFULLY THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS BECAUSE THEY CONTAIN IMPORTANT INFORMATION, INCLUDING THE VARIOUS TERMS OF, AND CONDITIONS TO, THE TENDER OFFER. STOCKHOLDERS MAY OBTAIN A FREE COPY OF THE TENDER OFFER STATEMENT ON SCHEDULE TO, THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND OTHER DOCUMENTS THAT BMCA WILL SHORTLY BE FILING WITH THE SECURITIES AND EXCHANGE COMMISSION AT THE COMMISSION'S WEBSITE AT WWW.SEC.GOV. STOCKHOLDERS ARE URGED TO CAREFULLY READ THESE MATERIALS PRIOR TO MAKING ANY DECISION WITH RESPECT TO THE TENDER OFFER.

# # #

FORWARD-LOOKING STATEMENTS

This release contains some forward-looking statements as defined by the federal securities laws which are based on our current expectations and assumptions, which are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated, projected or implied. We undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.

2

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[Letterhead of BMCA]
For more information, contact Building Materials Corporation of America at 973-317-5960
BMCA ANNOUNCES COMMENCEMENT OF ITS TENDER OFFER TO ACQUIRE ELKCORP FOR $40 PER SHARE CASH CONSIDERATION

EX-99.(A)(1)(O)

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Exhibit (a)(1)(O)

[Letterhead of BMCA]

December 18, 2006

Board of Directors
ElkCorp
14911 Quorum Drive, Suite 600
Dallas, TX 75254-1491

Ladies and Gentlemen:

        This is to advise you that BMCA is raising its tender offer price from $35 to $40 per share cash consideration for all Elk shares.

        We were surprised and disappointed by your announcement today that you have agreed to a leveraged buyout for Elk involving management participation, as this was done without once contacting us regarding our proposal to buy Elk or providing an opportunity for BMCA to bid. As you know, BMCA advised Elk more than four weeks ago, on November 15th, that BMCA was in a position to consider increasing its $35 per share price. Finally, instead of encouraging BMCA to maximize the value of its offer, to add insult to injury, your advisors attempted, in a 3:49 AM email on Monday morning, to persuade us to defer making the tender offer to your shareholders that we had informed you about on Sunday night. How could these actions possibly be in the interests of Elk shareholders?

        While you have not communicated the details of your leveraged buyout, we trust that you have not agreed to anything that would prevent us from competing economically and in effect preclude a higher offer for your shareholders. Finally, our offer is obviously superior to the Elk leveraged buyout in both price and the fact that BMCA's offer is a tender offer, not subject to regulatory clearance, and, barring any undue delay on the part of Elk, should close in January 2007.

        Please advise us how you wish to proceed.

        All the best.

Sincerely,

/s/  ROBERT B. TAFARO

Robert B. Tafaro
President and Chief Executive Officer

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[Letterhead of BMCA]

EX-99.(A)(1)(P)

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Exhibit (a)(1)(P)

[Letterhead of BMCA]

FOR IMMEDIATE RELEASE

For more information, contact Building Materials Corporation of America at 973-317-5960

BMCA COMMENCES TENDER OFFER TO PURCHASE ALL OUTSTANDING
SHARES OF COMMON STOCK OF ELKCORP AT $40.00 PER SHARE

        December 20, 2006—Building Materials Corporation of America ("BMCA"), North America's largest roofing manufacturer, which operates under the name GAF Materials Corporation, today commenced a tender offer to purchase all the outstanding shares of common stock of ElkCorp, par value $1.00 per share, at a price of $40.00 per share. The tender offer is scheduled to expire at 5:00 p.m., New York City time, on January 23, 2007.

        The tender offer materials are also being filed today with the SEC. The complete terms and conditions of the offer are set forth in the Offer to Purchase, copies of which can be obtained by contacting the information agent, D. F. King & Co., Inc. at (888) 628-9011. The Bank of New York is acting as the depositary. Willkie Farr & Gallagher LLP is acting as legal advisor to BMCA.

# # #

BMCA INFORMATION

        Building Materials Corporation of America, which operates under the name of GAF Materials Corporation, is an indirect subsidiary of G-I Holdings Inc. With annual sales in 2005 approximating $2.0 billion, BMCA is North America's largest manufacturer of residential and commercial roofing products and specialty building products.

# # #

        THIS PRESS RELEASE IS FOR INFORMATIONAL PURPOSES ONLY AND DOES NOT CONSTITUTE AN OFFER TO BUY OR THE SOLICITATION OF AN OFFER TO SELL SHARES OF ELKCORP COMMON STOCK. THE TENDER OFFER IS BEING MADE ONLY PURSUANT TO THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS THAT BMCA WILL SHORTLY BE DISTRIBUTING TO ELKCORP'S STOCKHOLDERS AND HAS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION. STOCKHOLDERS SHOULD READ CAREFULLY THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND RELATED MATERIALS BECAUSE THEY CONTAIN IMPORTANT INFORMATION, INCLUDING THE VARIOUS TERMS OF, AND CONDITIONS TO, THE TENDER OFFER. STOCKHOLDERS MAY OBTAIN A FREE COPY OF THE TENDER OFFER STATEMENT ON SCHEDULE TO, THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND OTHER DOCUMENTS THAT BMCA HAS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION AT THE COMMISSION'S WEBSITE AT WWW.SEC.GOV. STOCKHOLDERS ARE URGED TO CAREFULLY READ THESE MATERIALS PRIOR TO MAKING ANY DECISION WITH RESPECT TO THE TENDER OFFER.

# # #

FORWARD-LOOKING STATEMENTS

This release contains some forward-looking statements as defined by the federal securities laws which are based on our current expectations and assumptions, which are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated, projected or implied. We undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.

QuickLinks

[Letterhead of BMCA]
For more information, contact Building Materials Corporation of America at 973-317-5960
BMCA COMMENCES TENDER OFFER TO PURCHASE ALL OUTSTANDING SHARES OF COMMON STOCK OF ELKCORP AT $40.00 PER SHARE

EX-99.(A)(1)(Q)

Exhibit (a)(1)(Q)

January 5, 2007

Special Committee of the Board of Directors of ElkCorp
c/o Mark Gordon, Esq.
Wachtell, Lipton, Rosen & Katz
51 West 52nd Street
New York, NY 10019

Ladies and Gentlemen:

        On Friday, December 29, 2006, our Companies entered into confidentiality and standstill agreements, under which BMCA has been promised access to reasonable diligence in order to create a level playing field and enable it to maximize value to Elk shareholders.

        Notwithstanding the agreement, progress in terms of the due diligence process has proven, at least until late yesterday afternoon, frustratingly slow. By way of background, after signing the confidentiality agreement last Friday, BMCA's management team offered to travel to Dallas and work with Elk over the holiday weekend. Elk declined to do so, finally scheduling a conference call at noon on Tuesday. On this call, the only Elk management representative was Tom Karol, while other members of Elk management who presumably would have been in a position to respond to a number of our due diligence inquiries were for some reason excluded.

        Moreover, on the same conference call, raising questions as to whether we were entitled to the most basic information, Tom declined to respond to approximately 25 separate, entirely appropriate inquiries. By way of just one example, we were unable to obtain, or even receive a commitment to furnish, information concerning the Company's financial performance in October, November, and December 2006. Although Tom promised to reconsider his position at a subsequent time, and has since agreed to provide the requested information, it has been painfully slow in coming. In this connection, while BMCA's due diligence team was scheduled to meet with Tom and three other Elk executives this morning in Dallas, this meeting had to be postponed because information we had been promised by Elk had not been made available as of the time our people had to leave for the airport yesterday afternoon. Since that time, we have confirmed a rescheduled meeting for Saturday morning and are at last in the process of receiving meaningful due diligence information.

        Given the background of Elk's entire process, which we understand began 4-5 months ago, together with our recent experience, I think you can well understand our concern. As you know, although BMCA is Elk's most logical merger partner, the process had proceeded for months with a number of management buyout firms without so much as an invitation to BMCA to participate. Then when we surfaced with our proposal, which included a clear statement that we were willing to consider paying more, we were, for all intents and purposes, shut out of the process because we were unwilling, not surprisingly, to sign an extremely onerous standstill agreement whose principal points we were told were not subject to negotiation. And then without so much as calling BMCA to provide it with an opportunity to increase its merger price proposal, Elk proceeded to enter into an agreement with Carlyle, at a price now shown to be inferior, obligating Elk to pay a $29 million breakup fee.

        On another issue, Tom and your advisors requested this past Tuesday information about the merger process. Since then, we and your advisors have had a number of conversations regarding the

process and our currently pending tender offer. While we do not believe that there should be any ambiguity, perhaps in an excess of caution, we again summarize the state of play as follows:

        1.    Tender Offer. BMCA has pending a tender offer for all shares of ElkCorp common stock at $40 per share, in cash, not subject to a diligence or financing condition. We are ready, willing and able to close the tender offer subject to the satisfaction of the conditions to the offer. Satisfaction of the principal conditions are within ElkCorp's control. You need only lift the Rights Plan, and waive the application of Delaware 203 and Article Thirteen of your Certificate of Incorporation. As disclosed in the offer, we would then pursue a second step merger at the same price per share as the tender offer; or

        2. Negotiated Merger Agreement. Alternatively, we understand the interest Elk has expressed in managing any further rounds of this bidding contest and moving toward a negotiated merger agreement. To that end, we have delivered a draft agreement that is superior to the Carlyle agreement in both timing and price, and at least as strong as the Carlyle agreement with regard to every other contractual provision. We have received your advisors' comments on that agreement and our financing letters. In response, we have redrafted the merger agreement accepting all reasonable proposals and the financing letters which now address the three specific issues they raised as concerns. These documents will be returned to your advisors today.

        In order to put BMCA on a level playing field in this bidding contest, we agreed Friday night that Elk would provide access to reasonable due diligence but in no event less than what was provided to Carlyle. We encouraged Elk to do this because we believe that only by being on a level playing field with Carlyle can we deliver a binding merger agreement with terms acceptable to you and participate most effectively in any further rounds of the current bidding contest. Whatever the faults of the process to date, it should be readily apparent that a fair process and a level playing field will deliver the most value to Elk's shareholders.

        Given the pendency of our tender offer and our delivery of draft documents for a negotiated merger agreement, we do not understand how the Special Committee can maintain its current recommendation of the Carlyle offer. Our $40 offer, on substantially the same terms as your current Merger Agreement, is a "Superior Proposal" that we think compels your Board to consider a Change of Recommendation. We therefore urge you to provide the notice required by Section 5.3(d) of your current Merger Agreement to CGEA Holdings, Inc.

        As I think is plainly apparent, we are seriously committed to concluding the Elk-BMCA merger, and we trust that your Committee will do the right thing so that we will both be in a position to close this transaction at the earliest possible time. In the meantime, if you have any questions the Committee should like to discuss, Sam Heyman and I will be pleased to meet with the Special Committee at its earliest convenience.

Sincerely,

/s/ Robert B. Tafaro Robert B. Tafaro
President and Chief Executive Officer

cc:

Mr. Thomas D. Karol, CEO
Mr. Lee Lebrun, UBS

2

EX-99.(A)(1)(R)

Exhibit (a)(1)(R)

January 9, 2007

Special Committee of the Board of Directors of ElkCorp
c/o Mark Gordon, Esq.
Wachtell, Lipton Rosen & Katz
51 West 52nd Street
New York, NY 10019

Ladies and Gentlemen:

        We have reviewed the 14D9 Elk filed late yesterday afternoon and hasten to reply. While we appreciate the Committee's commitment to continue the due diligence process with a view toward entering into a mutually satisfactory merger agreement, we were surprised by the multitude of inaccuracies and the adversarial tone and emphasis of the document.

        By way of just one example, the 14D9 suggests that BMCA's pending tender offer is conditioned on due diligence. In point of fact, nothing could be further from the truth, as its express terms make clear and our January 5^th letter confirms. The offer does include quite naturally conditions customary in tender offers made without confidential information, such as its material adverse change provision. There should be nothing surprising about an offer made without the assistance of due diligence—which the Committee had denied us at the time of the filing of the offer—where an offeror seeks to protect itself in the event of a material adverse change. All that being said, BMCA continues to be willing to proceed on the terms of its pending tender offer.

        When the Committee, however, stated its interest in substantially narrowing the tender offer conditions, BMCA and the Committee agreed to negotiate a two-step tender and merger agreement on terms equal or superior to Elk's Carlyle agreement, and to include new terms more appropriate for an agreement made with confidential information. To this end, we entered into confidentiality and standstill agreements to provide BMCA with access to due diligence so as to be able to reach a merger agreement with the Committee with substantially narrower conditions. With regard to the material adverse change provision mentioned above, for example, BMCA agreed that it would substantially narrow the material adverse change provision after you had taken us through, and gotten us comfortable with, the Company's recent operating performance and plan for 2007.

        Notwithstanding Elk's agreement to provide reasonable due diligence—and I would acknowledge that the pace has accelerated markedly in the last several days—it continues to be a challenging process. With all due respect, we believe this results from a process that has been flawed from the very beginning wherein access to information, negotiation of the agreements, and other aspects of the process are being managed by a Chief Executive, who is for all intents and purposes a competing bidder, and an investment banker, who at least in the early stages of the process was working with senior management, before the involvement of the Special Committee, to assist it, among other things, in interesting a management buyout partner. Not surprisingly, this process has already exposed the Elk Board and Members of the Special Committee to several serious lawsuits.

        Despite our recent progress on the due diligence front, you should know that any number of our reasonable diligence requests are still being filibustered by management and its advisors. By way of several recent examples, we are currently being denied access to any information concerning Elk's December performance, information concerning Elk's material contracts and obligations, and the Company's most recent outlook and plan for 2007. These requests are well within the scope of any normal diligence and should not be the subject of negotiation.

        Although we have made plain at the outset that BMCA's offer is not conditioned upon financing, we nonetheless furnished the Committee with copies of our financing commitments to which the Company's 14D9 now takes issue. By way of background, when your advisors questioned the form of our financing commitments, claiming that they were not as precise or strong as Carlyle's, we asked the Committee to furnish us with the forms of commitment provided by Carlyle so that we could work with our underwriters to refine the commitments accordingly. Unfortunately, BMCA has still not received an answer to this request made about two weeks ago and restated as recently as this past Sunday afternoon.

        By way of further background concerning BMCA's financing commitments, approximately two weeks ago the Company's advisors provided comments on our financing commitments, citing three concerns. We immediately conferred with BMCA's underwriters, redrafted the commitments to address the three issues, and the revised financing commitments were delivered to the Committee last Friday. Then after having had our original financing commitments for three weeks, ELK forwarded on Saturday night (just in time to make it into the 14D9!), an extensive list of new "issues" involving primarily mechanical form-over-substance considerations which had not been raised before—obviously not leaving time to respond before the filing of the Committee's 14D9. Among the issues raised by the Company's advisors were many that had already been resolved or were clearly inappropriate.

        Moreover, there are other material inaccuracies in your 14D9, too many to enumerate here. By way of just one example, you cite the need for BMCA note holder consents as a condition of the tender even though we announced on Friday and informed Elk's advisors on Sunday that the consents have already been received. More generally, it would be constructive if BMCA were given a meaningful chance to respond to Elk's advisors' concerns, both real and illusory, before they become the basis of the Committee's decisions.

        We are confident that our proposal is superior, we are absolutely committed to concluding this transaction and maximizing value for Elk shareholders, and we stand ready to work with you towards a negotiated transaction. Finally, we renew our earlier suggestion to meet directly with the Special Committee and its advisors so as to correct any needless misunderstanding and assure that the process from here moves forward in the most constructive fashion.

Sincerely,

Robert B. Tafaro

President and Chief Executive Officer

cc:

Mr. Thomas D. Karol, CEO
Mr. Lee Lebrun, UBS

2

EX-99.(A)(1)(S)

Exhibit (a)(1)(S)

January 18, 2007

Special Committee of the Board of Directors of ElkCorp
c/o Mark Gordon, Esq.
Wachtell Lipton Rosen & Katz
51 West 52nd Street
New York, NY 10019

Ladies and Gentlemen:

        This is to advise you that BMCA, through its acquisition subsidiary, has raised its tender offer price this morning from $40 to $42 per share cash consideration for all Elk shares, effectively superseding BMCA's previous tender offer. In addition, J.P. Morgan Securities has joined our bank consortium with Deutsche Bank and Bear Stearns, and we have financing commitments, in the form you requested, sufficient to fund the full price of the transaction.

        We were again disappointed by your announcement on Tuesday that you have entered into a revised merger transaction with Carlyle, with Elk's CEO to be a partner in the buyout group, without notice to BMCA affording it the opportunity to increase its bid. As you know, we were, until the Tuesday announcement, making substantial progress toward a mutually acceptable merger agreement, had received revised financing commitments in the form you requested, and performed due diligence. In the latter connection, as a result of the hard work of my BMCA colleagues and their Elk counterparts, working sometimes around the clock over the past two weeks, we have managed to finish a substantial portion of the same due diligence that Carlyle had been working on for some months.

        We believe that the action taken by Elk on Tuesday represents an attempt to prematurely terminate the auction process. At the same time, Elk unilaterally terminated the due diligence process. The fact that we are in a competitive situation only underscores our need for the balance of the due diligence information so that we can participate on a level playing field and have the opportunity to maximize value for Elk shareholders.

        Based upon BMCA's increased tender offer price, our offer is clearly superior to Carlyle's revised offer, and we urge that the due diligence process be resumed so as to enable BMCA to eliminate certain tender offer conditions, as BMCA and Elk had already agreed subject to satisfactory completion of due diligence. We are highly committed to this transaction and stand ready to conclude a mutually agreeable negotiated transaction at the earliest possible time.

Sincerely,

Robert B. Tafaro
President and Chief Executive Officer

cc:

Mr. Thomas D. Karol, CEO
Mr. Lee Lebrun, UBS

EX-99.(B)(1)

Exhibit (b)(1)

DEUTSCHE BANK AG
NEW YORK BRANCH
DEUTSCHE BANK
SECURITIES INC.
60 Wall Street
New York, NY 10005 BEAR STEARNS
CORPORATE LENDING INC.
BEAR STEARNS & CO. INC.
383 Madison Avenue
New York, NY 10179 JPMORGAN CHASE BANK, N.A.
J.P. MORGAN SECURITIES INC.
270 Park Avenue
New York, NY 10017

January 17, 2007

Building Materials Corporation of America,
BMCA Acquisition Inc. and
BMCA Acquisition Sub Inc.
1361 Alps Road
Wayne, New Jersey 07470

Attention: John Maitner

Re:

Acquisition Financing—Senior Secured Financing Commitment Letter

Ladies and Gentlemen:

        You have informed Deutsche Bank AG New York Branch ("DBNY"), Deutsche Bank Securities Inc. ("DBSI" and, together with DBNY, "DB"), Bear, Stearns & Co. Inc. ("Bear Stearns"), Bear Stearns Corporate Lending Inc. ("BSCL"), JPMorgan Chase Bank, N.A. ("JPMCB") and J.P. Morgan Securities Inc. ("JPMorgan" and together with DB, Bear Stearns, BSCL and JPMCB collectively, the "Committing Parties") that BMCA Acquisition Sub Inc. (the "Purchaser"), a wholly-owned direct subsidiary of BMCA Acquisition Inc. and an indirect wholly-owned subsidiary of Building Materials Corporation of America ("BMCA" and together with the Purchaser and BMCA Acquisition Inc., the "Company") intends to offer to acquire through a tender offer (the "Tender Offer") for up to $42 in cash per share all of the outstanding shares (and associated Series A Preference Stock Rights) of common stock, $1.00 par value (the "Company Stock"), of ElkCorp, a Delaware corporation ("Elk"), but in any event not less than sufficient shares of Company Stock to enable the Purchaser—voting without any other shareholders of Elk, (other than Heyman Investment Associates Limited Partnership ("HIA") which has agreed to sell to you at its cost its shares of Elk) to approve a merger of the Purchaser with Elk. As soon as practicable after the closing of the Tender Offer (the "Closing Date"), the Purchaser will consummate a merger with Elk (the "Merger" and together with the Tender Offer, the "Acquisition"). You have also informed the Committing Parties that concurrently with the closing of the Tender Offer you intend to refinance substantially all of the existing indebtedness of BMCA (excluding the 7.75% Notes due 2014 (the "2014 Notes"), which will be equally and ratably secured with the Term Loan Facility (as defined below) and that concurrently with the consummation of the Merger you intend to refinance all of the existing indebtedness of Elk (collectively, the "Refinancing"). We understand that you desire to establish a senior secured credit facility in an aggregate principal amount of $1,550 million (the "Senior Secured Financing") the proceeds of which will be used (together with the funds provided by the financing referred to in the succeeding paragraph) (x) for the purchase price to be paid to effect the Tender Offer, (y) to effect the Refinancing and (z) to pay fees and expenses payable in connection with the Transaction (as defined below).

        The sources of funds needed to effect the Tender Offer, the Merger and the Refinancing, to pay all fees and expenses incurred in connection with the Transaction and to provide for the working capital needs and general corporate requirements of you and your subsidiaries after giving effect to the Tender Offer and the Merger shall be provided solely through (i) a bridge financing or by the issuance by you (either pursuant to private placement or underwritten public sale) of senior secured notes (the

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"Senior Secured Notes") which shall generate $325 million of gross cash proceeds (calculated before underwriting fees) and (ii) the Senior Secured Financing (with the transactions described in preceding clauses (i) and (ii) being herein collectively referred to as the "Financing Transactions" and, together with the Acquisition and the Refinancing, being herein collectively referred to as the "Transaction").

        We understand that the Senior Secured Financing shall consist of (i) up to an $950 million term loan facility (the "Term Loan Facility") and (ii) a $600 million revolving credit facility (the "Revolving Credit Facility" and, together with the Term Loan Facility, the "Credit Facilities"); it being understood that at or prior to the Merger you may elect to increase the Revolving Credit Facility by up to $100 million provided that the Term Loan Facility is reduced by an equal amount and that not more than $150 million or such greater amount if the Revolving Credit Facility is so increased (plus seasonal working capital requirements) or such greater amount as may be mutually agreed of the proceeds of the Revolving Credit Facility may be utilized to make payments owing to effect the Transaction or to pay any fees and expenses incurred in connection with the Transaction. Any commitments under the Term Loan Facility not required to finance the Transaction will terminate on the date of the consummation of the Merger. A summary of certain of the terms and conditions of the Revolving Credit Facility and Term Loan Facility is set forth in Exhibit A attached hereto (the "Term Sheet").

        Subject to the terms and conditions set forth herein and in the Term Sheet, (a) DBNY is pleased to confirm (i) its several and not joint commitment to provide 50% of each Credit Facility and (ii) its agreement to act as sole administrative agent (in such capacity, the "Administrative Agent") for a syndicate of lenders who will participate in the Senior Secured Financing (together with DBNY, BSCL and JPMCB, the "Lenders"), (b) BSCL is pleased to confirm its several and not joint commitment to provide 35% of each Credit Facility, (c) DBSI is pleased to confirm its agreement to act as a Joint Lead Arranger and Joint Book Running Manager for the Senior Secured Financing, (d) Bear Stearns is pleased to confirm its agreement to act as a Joint Lead Arranger and Joint Book Running Manager for the Senior Secured Financing, (e) JPMCB is pleased to confirm its several and not joint commitment to provide 15% of each Credit Facility, and (f) JPMorgan is pleased to confirm its agreement to act as a Joint Lead Arranger and Joint Book Running Manager for the Senior Secured Financing. One or more other institutions may be designated as "Syndication Agent", "Documentation Agent" or such other titles as may be deemed appropriate or desirable in connection with the syndication of the Senior Secured Financing (each of which shall participate appropriately in the Credit Facilities), DBSI, Bear Stearns and JPMorgan, as Joint Lead Arrangers are referred to herein as the "Lead Arrangers". It being understood and agreed that the DBSI name shall appear immediately to the left of Bear Stearns and that the Bear Stearns name shall appear immediately above or immediately to the left of JPMorgan with respect to the Term Loan Facility and that DBSI name shall appear immediately to the left of JPMorgan and that the JPMorgan name shall appear immediately above or immediately to the left of Bear Stearns name with respect to the Revolving Credit Facility.

        DBNY, BSCL and JPMCB (collectively, the "Initial Lenders") reserve the right, prior to or after execution of the definitive credit documentation for the Senior Secured Financing (the "Operative Documents") to syndicate all or part of their respective commitments hereunder to one or more other Lenders reasonably acceptable to you that will become party to such definitive credit documentation pursuant to a syndication to be managed by the Lead Arrangers in consultation with you. You agree that, upon delivery to the Lead Arrangers of a commitment letter addressed to the Company for all or a portion of the Senior Secured Financing containing terms not less favorable in any material respect to the Company than the terms hereof by a Lender that you have introduced to the Lead Arrangers as a potential Lender, the Initial Lenders shall be proportionally relieved of their respective obligations hereunder based on their relative commitments hereunder to the extent of such Lender's commitments set forth in such commitment letter. Furthermore, all aspects of the syndication of the Senior Secured Financing, including, without limitation, timing, potential syndicate members to be approached, titles, allocations and division of fees, shall be determined by the Lead Arrangers in consultation with you.

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You agree to actively assist the Lead Arrangers in forming a syndicate acceptable to the Lead Arrangers and you, including by using your commercially reasonable efforts to ensure that the Lead Arrangers' syndication efforts benefit materially from your existing lending relationships, and to provide the Lead Arrangers and the Lenders, upon reasonable request, with all information reasonably deemed necessary by the Lead Arrangers to complete successfully the syndication, including, but not limited to, projections and other information prepared by you or your affiliates or advisors relating to the Transaction. You also agree (i) to make available your senior management and appropriate representatives to participate in information meetings with ratings agencies identified by Lead Arrangers and potential Lenders, in each case at such times and places as the Lead Arrangers may reasonably request, and (ii) at the request of the Lead Arrangers, to assist in the preparation of a version of a confidential information memorandum to be used in connection with the syndication of the Senior Secured Financing, consisting exclusively of information and documentation that is either (i) publicly available with respect to the Borrower, Elk or their respective subsidiaries or (ii) not material with respect to the Borrower and its subsidiaries or any of their respective securities for purposes of United States Federal and state securities laws (all such information and documentation being "Public Information"). Any information and documentation that is not Public Information is referred to herein as "Private Information". You further agree that each document to be disseminated by the Administrative Agent to any Lender in connection with the Credit Facilities will be identified by you as either (i) containing Private Information or (ii) containing solely Public Information. The provisions of the fourth sentence and clause (ii) of the fifth sentence of this paragraph shall remain in full force and effect until the successful syndication of the Senior Secured Financing (as reasonably determined by the Lead Arrangers).

        You represent, warrant and covenant that (i) no written information, other than business and financial projections, budgets, pro forma data and forecasts, that has been or is hereafter furnished by you or on your behalf to the Lead Arrangers, any Lender or any prospective Lender in connection with the Transaction and (ii) no other information given at information meetings for potential syndicate members and supplied or approved by you or on your behalf (such written information and other information being referred to herein collectively as the "Information") taken as a whole contained (or, in the case of Information furnished after the date hereof, will contain), as of the time it was (or hereafter is) furnished, any material misstatement of fact or omitted (or will omit) as of such time to state any material fact necessary to make the statements therein taken as a whole not misleading, in the light of the circumstances under which they were (or hereafter are) made; provided, however, that, with respect to Elk and its subsidiaries, the foregoing representation is limited to your best knowledge. With respect to business and financial projections (including detailed consolidated financial statements for the seven fiscal years ending after the Closing Date), budgets, pro forma data and forecasts, if any (collectively, the "Projections"), that have been or will be prepared by you or on your behalf and has been or is hereafter furnished by you or on your behalf to the Lead Arranger, any Lender or any prospective Lender in connection with Transaction, no representation, warranty or covenant is made other than that the Projections have been (and, in the case of Projections furnished after the date hereof, will be) prepared in good faith based on assumptions believed to be reasonable at the time of preparation thereof (it being understood that such Projections are subject to significant uncertainties and contingencies, many of which are beyond the Company's control, and that no assurance can be given that the Projections will be realized). You agree to supplement the Information and the Projections from time to time until the date of the initial borrowing under the Senior Secured Financing, as appropriate, so that the representations and warranties in the preceding sentence remain correct. You understand that, in syndicating the Senior Secured Financing, the Lead Arranger will use and rely on the Information and the Projections without independent verification thereof.

        The Committing Parities' commitments and other agreements hereunder are subject to (a) there not occurring any condition or circumstance which has had, or would reasonably be expected to have, a Material Adverse Effect (as defined below), (b) the accuracy and completeness in all material respects

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of the representations that the Company makes to Lead Arrangers and the Lenders pursuant to the immediately preceding paragraph, (c) the Company's compliance with the terms of this Commitment Letter (as defined below), and (d) the Lead Arrangers' reasonable satisfaction that prior to the earlier of (i) four months after the date on which the Operative Documents shall become effective and (ii) a Successful Syndication (as defined in the fee letter agreement dated the date hereof among the parties hereto, the "Fee Letter") there shall be no offering, placement or arrangement by you or on your behalf of any debt securities or bank financing (including refinancings and renewals of debt, but excluding the Senior Secured Notes and any ordinary course financing or refinancing of equipment purchases or leases) and (e) the other conditions referred to in the Term Sheet.

        "Material Adverse Effect" means any fact, circumstance, event, change, effect or occurrence since June 30, 2006 that has or would be reasonably likely to have a material adverse effect on the business, results of operation or financial condition of Elk and its subsidiaries, taken as a whole, but, in any case, shall not include facts, circumstances, events, changes, effects or occurrences (a) generally affecting the industries in which Elk and its subsidiaries operate (including general pricing changes), or the economy or the financial or securities markets in the United States or elsewhere in the world (including any regulatory and political conditions or developments, or any outbreak or escalation of hostilities, declared or undeclared acts of war or terrorism), except to the extent any fact, circumstance, event, change, effect or occurrence that, relative to other industry participants, disproportionately impacts the assets, properties, business, results of operation or financial condition of Elk and its subsidiaries, taken as a whole, (b) resulting from the announcement of (i) the proposal of the Acquisition or (ii) the Transaction or (c) resulting from any litigation related to the proposed Acquisition or the Transaction and provided that any failure to meet internal or published projections, forecasts or revenue or earning predictions for any period shall not, in and of itself, constitute a Material Adverse Effect.

        To induce the Committing Parties to issue this letter (together with the Term Sheet, this "Commitment Letter") and to proceed with the documentation of the Senior Secured Financing, you hereby agree that all fees and expenses (including the reasonable fees and expenses of counsel and consultants) of the Committing Parties and their respective affiliates arising in connection with this Commitment Letter and in connection with the Transaction and other transactions described herein (including in connection with our due diligence and syndication efforts) shall be for your account, whether or not the Transaction is consummated or the Senior Secured Financing is made available or the Operative Documents are executed. You further agree to indemnify and hold harmless the Administrative Agent, each Lead Arranger, and each other agent or co agent (if any) designated by the Committing Parties with respect to the Senior Secured Financing (each, an "Agent"), each Lender (including in any event each Initial Lenders) and their respective affiliates and each director, officer, employee, representative and agent thereof (each, an "Indemnified Person") from and against any and all actions, suits, proceedings (including any investigations or inquiries), claims, losses, damages, liabilities or expenses of any kind or nature whatsoever which may be incurred by or asserted against or involve any Agent, any Lender or any other such Indemnified Person as a result of or arising out of or in any way related to or resulting from the Transaction or this Commitment Letter and, upon demand, to pay and reimburse each Agent, each Lender and each other Indemnified Person for any reasonable legal or other out of pocket expenses paid or incurred in connection with investigating, defending or preparing to defend any such action, suit, proceeding (including any inquiry or investigation) or claim (whether or not any Agent, any Lender or any other such Indemnified Person is a party to any action or proceeding out of which any such expenses arise); provided, however, that you shall not have to indemnify any Indemnified Person against any loss, claim, damage, expense or liability to the extent same resulted from the gross negligence or willful misconduct of the respective Indemnified Person (as determined in a proceeding of a court of competent jurisdiction). Neither the Committing Parties nor any other Indemnified Person shall be responsible or liable to you or any other person or entity for (x) any determination made by it pursuant to this Commitment Letter in the absence of gross negligence or willful misconduct on the part of such person or entity (as determined in a proceeding of

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a court of competent jurisdiction), (y) any damages arising from the use by others of information or other materials obtained through electronic, telecommunications or other information transmission systems or (z) any indirect, special, incidental, punitive or consequential damages (including, without limitation, any loss of profits, business or anticipated savings) which may be alleged as a result of this Commitment Letter or the financing contemplated hereby.

        Each Lead Arranger reserves the right to employ the services of its affiliates (including, in the case of DB, Deutsche Bank AG) in providing services contemplated by this Commitment Letter and to allocate, in whole or in part, to its affiliates certain fees payable to such Lead Arranger in such manner as such Lead Arranger and its affiliates may agree in their sole discretion. You also agree that the Initial Lenders may at any time and from time to time assign all or any portion of their respective commitments hereunder to one or more of their respective affiliates. You further acknowledge that (i) the Committing Parties may share with any of their respective affiliates, and such affiliates may share with the applicable Committing Party, any information related to the Transaction, you and Elk (and your respective subsidiaries and affiliates), or any of the matters contemplated hereby and (ii) the Committing Parties and their respective affiliates may be providing debt financing, equity capital or other services (including financial advisory services) to other companies in respect of which you or Elk may have conflicting interests regarding the transactions described herein and otherwise. Each Committing Party agrees to treat, and cause any such affiliate to treat, all non public information provided to it by you or on your behalf as confidential information in accordance with customary banking industry practices.

        Except as otherwise agreed in writing between us, you agree that this Commitment Letter is for your confidential use only and that, unless the Lead Arrangers have otherwise consented, neither its existence nor the terms hereof will be disclosed by you to any person or entity other than your officers, directors, employees, accountants, attorneys and other advisors, and then only on a "need to know" basis in connection with the transactions contemplated hereby and on a confidential basis. Notwithstanding the foregoing, following your acceptance of the provisions hereof and your return of an executed counterpart of this Commitment Letter and the Fee Letter to us as provided below, (i) you shall be permitted to furnish a copy of this Commitment Letter (but not the Fee Letter) to Elk and its advisors in connection with the proposed Acquisition, (ii) you may make public disclosure of the existence and amount of the commitments hereunder and of the identity of the Administrative Agent and the Lead Arrangers, (iii) you may file a copy of this Commitment Letter (but not the Fee Letter) in any public record in which it is required by law to be filed and (iv) you may make such other public disclosure of the terms and conditions hereof as, and to the extent, you believe in good faith, after consulting with counsel, is required by law or in connection with complying with a court order. If this Commitment Letter is not accepted by you as provided below, please immediately return this Commitment Letter (and any copies hereof) to the undersigned.

        You hereby represent and acknowledge that, to the best of your knowledge, neither the Committing Parties, nor any employees or agents of, or other persons affiliated with, the Committing Parties, have directly or indirectly made or provided any statement (oral or written) to you or to any of your employees or agents, or other persons affiliated with or related to you (or, so far as you are aware, to any other person), as to the potential tax consequences of the Transaction.

        The provisions of the four immediately preceding paragraphs shall survive any termination of this Commitment Letter.

        In order to comply with the USA PATRIOT Act, DB must obtain, verify and record information that sufficiently identifies each entity (or individual) that enters into a business relationship with the Committing Parties. As a result, in addition to your corporate name and address, DB will obtain your corporate tax identification number and certain other information. DB may also request relevant corporate resolutions and other identifying documents.

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        This Commitment Letter and the Fee Letter (and your rights and obligations hereunder and thereunder) shall not be assignable by you to any person or entity without the prior written consent of the Committing Parties (and any purported assignment without such consent shall be null and void). This Commitment Letter and the Fee Letter may not be amended or modified, or any provision hereof and thereof waived, except by an instrument in writing signed by you and the Committing Parties. Each of this Commitment Letter and the Fee Letter may be executed in any number of counterparts, each of which shall be an original and all of which, when taken together, shall constitute one agreement. Delivery of an executed signature page of this Commitment Letter or the Fee Letter by facsimile (or other electronic) transmission shall be effective as delivery of a manually executed counterpart hereof or thereof, as the case may be. This Commitment Letter and the Fee Letter shall be governed by, and construed in accordance with, the law of the State of New York. This Commitment Letter and the Fee Letter set forth the entire agreement among the parties hereto as to the matters set forth herein. This Commitment Letter and the Fee Letter shall supersede all prior communications, written or oral, with respect to the matters herein. Matters that are not covered or made clear herein, in the Term Sheet or in Fee Letter are subject to mutual agreement of the parties hereto. This Commitment Letter and the Fee Letter are intended to be solely for the benefit of the parties hereto and thereto and are not intended to confer any benefits upon, or create any rights in favor of, any person or entity other than the parties hereto or thereto (and indemnified persons) and may not be relied upon by any person or entity other than you. Neither this Commitment Letter nor the Fee Letter are intended to create a fiduciary relationship among the parties hereto or thereto.

        Each of the parties hereto hereby waives any right to trial by jury with respect to any claim, action, suit or proceeding arising out of or contemplated by this Commitment Letter or the Fee Letter. You hereby submit to the non exclusive jurisdiction of the federal and New York state courts located in the county of New York in connection with any dispute related to this Commitment Letter, the Fee Letter or any matter contemplated hereby or thereby.

        The Committing Parties' commitments and other obligations with respect to the Senior Secured Financing as set forth above will terminate on the first to occur of (i) the date the Operative Documents become effective, (ii) June 30, 2007 or (iii) the date on which you have informed the Lead Arrangers that you have decided not to proceed with the Transaction.

*    *    *

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        If you are in agreement with the foregoing, please sign and return to DB the enclosed copy of this Commitment Letter, together with a copy of the enclosed Fee Letter, no later than 5:00 p.m., New York time, on January 31, 2007. Unless this Commitment Letter and the Fee Letter are signed and returned by the time and date provided in the immediately preceding sentence, this Commitment Letter shall terminate at such time and date.

Very truly yours,
DEUTSCHE BANK AG NEW YORK BRANCH
By:	/s/  ALBERT FISCHETTI Name: Albert Fischetti Title: Director
By:	/s/  STEPHEN CAYER Name: Stephen Cayer Title: Director
DEUTSCHE BANK SECURITIES INC.
By:	/s/  KEVIN SHERLOCK Name: Kevin Sherlock Title: Managing Director
By:	/s/  STEPHEN R. LAPIDUS Name: Stephen R. Lapidus Title: Director

BMCA Senior Secured Financing Commitment Letter

BEAR, STEARNS & CO. INC.
By:	/s/  LAWRENCE B. ALLETTO Name: Lawrence B. Alletto Title: Senior Managing Director
BEAR STEARNS CORPORATE LENDING INC.
By:	/s/  LAWRENCE B. ALLETTO Name: Lawrence B. Alletto Title: Vice President

BMCA Senior Secured Financing Commitment Letter

JPMORGAN CHASE BANK, N.A.
By:	/s/  THOMAS H. KOZLARK Name: Thomas H. Kozlark Title: Vice President
J.P. MORGAN SECURITIES INC.
By:	/s/  DAVID J. LYNCH Name: David J. Lynch Title: Vice President

BMCA Senior Secured Financing Commitment Letter

Agreed to and Accepted this            day of                        , 2007:
BUILDING MATERIALS CORPORATION OF AMERICA
By:	/s/ JOHN M. MAITNER Name: John M. Maitner Title: Vice President and Treasurer
BMCA ACQUISITION INC.
By:	/s/ JOHN M. MAITNER Name: John M. Maitner Title: Vice President and Treasurer
BMCA ACQUISITION SUB INC.
By:	/s/ JOHN M. MAITNER Name: John M. Maitner Title: Vice President and Treasurer

BMCA Senior Secured Financing Commitment Letter

Exhibit A

SUMMARY OF CERTAIN TERMS OF CREDIT FACILITIES

        Unless otherwise defined herein, capitalized terms used herein and defined in the letter agreement to which this Exhibit A is attached (the "Commitment Letter") are used herein as therein defined.

I.    Description of Credit Facilities

Borrower:	Building Materials Corporation of America ("BMCA"), BMCA Acquisition Inc., BMCA Acquisition Sub Inc. and certain other subsidiaries of BMCA as shall be mutually agreed (collectively the "Borrower").
Total Credit Facilities:	$1,550 million.
Credit Facilities:	1.	Term loan facility in an aggregate principal amount of up to $950 million (the "Term Loan Facility").
	2.	Revolving credit facility in an aggregate principal amount of $600 million (the "Revolving Credit Facility" and, together with the Term Loan Facility, the "Credit Facilities").
	3.	The Borrower may elect at or prior to the Merger to increase the Revolving Credit Facility by up to $100 million provided that the Term Loan Facility is reduced by an equal amount.

        A.    Term Loan Facility

Use of Proceeds:	The loans made pursuant to the Term Loan Facility (the "Term Loans") may only be incurred in two tranches, with the initial tranche ("Tranche I") on the Closing Date and the second tranche ("Tranche II") on the date of the Merger. The proceeds thereof shall be utilized solely to finance, in part, the Tender Offer, the Merger and the Refinancing and to pay the fees and expenses incurred in connection with the Transaction. The aggregate principal amount of Tranche I shall not be less than 50% of the aggregate principal amount of the Term Loan Facility.
Maturity:	The final maturity date of the Term Loan Facility shall be 7 years from the Closing Date (the "Term Loan Maturity Date").
Amortizations:	Annual amortization (payable in 4 equal quarterly installments) of the Term Loans shall be required in an amount equal to one percent of the initial aggregate principal amount of the Term Loans with the remaining aggregate principal amount payable on the Term Loan Maturity Date.
Availability:	Tranche I may only be incurred on the Closing Date. Tranche II may only be incurred on the date of the Merger, which will not be later than the later of (x) four months after the Closing Date and (y) June 30, 2007 (such later date being the "Tranche II Final Funding Date"). No amount of Term Loans once repaid may be reborrowed.

Security:	All amounts owing under the Term Loan Facility (and all obligations under the related Guaranties) will be secured by (x) a first priority perfected security interest in all stock, other equity interests and promissory notes owned by the Borrower and the Guarantors (which shall include the Company Stock acquired in the Tender Offer and acquired from HIA), provided, however, that not more than 65% of the total outstanding voting stock of any "controlled foreign corporation" shall be required to be pledged if the pledging thereof would give rise to material adverse tax consequences to the Borrower (as reasonably determined by the Borrower), and all other tangible and intangible assets (including, without limitation, equipment, contract rights, securities, securities accounts, patents, trademarks, other intellectual property and real estate) owned by the Borrower and the Guarantors, subject (in each case) to the same exceptions as provided under the Loan Documents (as such term is defined in the Amended and Restated Credit Agreement dated as of September 28, 2006, among BMCA, Citigroup USA, Inc., as administrative agent, and the other parties thereto (the "Existing Credit Agreement"; such Loan Documents, the "Existing Loan Documents") and additional exceptions as may be mutually agreed, but excluding the collateral for the Revolving Credit Facility and (y) a second priority perfected security interest in the collateral for the Revolving Credit Facility.
	All documentation evidencing the security required pursuant to the immediately preceding paragraph shall be in form and substance the same as provided under the Existing Loan Documents, with the same exceptions as provided by the Existing Loan Documents and such additional exceptions as may be mutually agreed.
	The collateral granted as security for the Term Loan Facility will secure equally and ratably the 2014 Notes and any untendered 8% Notes due 2007 and 2008 of BMCA.
Commitment Fee:	A per annum commitment fee in an amount to be determined (it is expected to be 50 basis points or as mutually agreed) on the undrawn portion of the commitment of each Lender under the Term Loan Facility, will commence accruing on the Closing Date and be payable quarterly in arrears and on the date of the Merger.

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Covenants:
(i) Substantially the same covenants as in the Existing Credit Agreement and (ii) as long as any obligations under the Term Loan Facility shall be outstanding, (x) a maximum total leverage ratio (i.e., funded indebtedness to adjusted EBITDA (to be defined in a manner as may be mutually agreed) on a pro forma basis after giving effect to the Transaction, (y) a minimum interest coverage ratio (i.e., adjusted EBITDA to all interest and other fees and expenses treated as interest under GAAP) on a pro forma basis after giving effect to the Transaction, and (z) a maximum capital expenditure limitation, in each case of (x), (y) and (z) at levels as may be mutually agreed with at least 25% cushion from the Borrower's projections, and in each case of (i) and (ii) above, such exceptions and baskets as are customary for term loan financings as may be mutually agreed and, where applicable, substantially the same as those in the Existing Credit Agreement and additional exceptions and increased baskets as may be mutually agreed, and except that the operational covenants will not be applicable to Elk and its subsidiaries until the Merger and there will be an affirmative covenant to require that if the Merger does not occur by the Tranche II Final Funding Date, the Borrower shall sell, or cause to be sold, the shares of Elk acquired in the tender offer no later than a date six months following the Tranche II Final Funding Date and with the proceeds thereof to be applied to repay the Term Loans.

        B.    Revolving Credit Facility

Use of Proceeds:	The proceeds of loans under the Revolving Credit Facility (the "Revolving Loans") shall be utilized for working capital, capital expenditures and general corporate purposes, provided that not more than $150 million or such greater amount if the Revolving Credit Facility is so increased at or prior to the Merger (plus seasonal working capital requirements) or such greater amount as may be mutually agreed of the proceeds of the Revolving Credit Facility may be utilized to pay amounts owing to effect the Acquisition or the Refinancing or to pay any fees and expenses incurred in connection with the Transaction.
Maturity:	The final maturity date of the Revolving Credit Facility shall be 5 years from the Closing Date (the "Revolving Loan Maturity Date").
Availability:	Revolving Loans may be borrowed, repaid and reborrowed on and after the Closing Date and prior to the Revolving Loan Maturity Date in accordance with the terms of the Operative Documents (which terms will be substantially the same as the terms of the Existing Credit Agreement).

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Letters of Credit:	Up to $150 million of the Revolving Credit Facility will be available for the issuance of stand by and trade letters of credit ("Letters of Credit") to support obligations of the Borrower and its subsidiaries on terms substantially the same as those contained in the Existing Credit Agreement. Maturities for Letters of Credit will not exceed twelve months in the case of standby Letters of Credit or 180 days in the case of trade Letters of Credit, renewable annually thereafter in the case of standby Letters or Credit and, in any event, shall not extend beyond the 30th business day prior to the Revolving Loan Maturity Date unless cash collateralized.
Borrowing Base:	Substantially the same as under the Existing Credit Agreement with respect to Eligible Receivables, Eligible Inventory and Eligible Precious Metals (each such term as defined in the Existing Credit Agreement); provided, however, that any Eligible Receivables, Eligible Inventory and Eligible Precious Metals of Elk and its subsidiaries shall be included in the Borrowing Base only after the Merger and the Lead Arrangers having received a reasonably satisfactory field examination and inventory appraisal with respect to such assets.
Security:	All amounts owing under the Revolving Credit Facility and (if applicable) the secured hedging agreements and cash management liabilities (and obligations under the related Guaranties) will be secured by a first priority perfected security interest in all receivables, inventory, platinum and rhodium, deposit accounts and other current assets of the Borrower and the Guarantors and proceeds thereof.
	All documentation evidencing the security required pursuant to the immediately preceding paragraph shall be in substantially the same form and substance as provided under the Existing Loan Documents, with the same exceptions as provided by the Existing Loan Documents and such additional exceptions as may be mutually agreed.
Optional Commitment Reductions:	Same as provided in the Existing Credit Agreement.
Cash Dominion:	A person to be appointed as the collateral agent for the secured parties will be granted cash dominion only if Available Liquidity (as defined in the Existing Credit Agreement) is below 10% of the Revolving Credit Facility or during the continuance of an Event of Default (to be defined in a manner consistent with such definition in the Existing Credit Agreement).
Commitment Fee:	A commitment fee, at a per annum rate of 0.30%, on the daily undrawn portion of the commitments of each Lender under the Revolving Credit Facility, will commence accruing on the Closing Date and will be payable quarterly in arrears, and will be subject to a leverage-based or utilization-based pricing grid.

A-4

Letter of Credit Fees:

A letter of credit fee equal to the Applicable Margin for Revolving Loans maintained as Eurodollar Loans on the outstanding stated amount of Letters of Credit (the "Letter of Credit Fee") to be shared proportionately by the Lenders under the Revolving Credit Facility in accordance with their participation in the respective Letter of Credit, and a facing fee of 1/4 of 1% per annum (but in no event less than $500 per annum for each Letter of Credit) (the "Facing Fee") to be paid to the issuer of each Letter of Credit for its own account, in each case calculated on the aggregate stated amount of all Letters of Credit for the stated duration thereof. Letter of Credit Fees and Facing Fees shall be payable quarterly in arrears. In addition, the issuer of a Letter of Credit will be paid its customary administrative charges in connection with Letters of Credit issued by it.

Covenants:

Substantially the same covenants as in the Existing Credit Agreement (with substantially the same exceptions and baskets as in the Existing Credit Agreement and additional exceptions and increased baskets as may be mutually agreed), including, without limitation, a minimum interest coverage ratio and a maximum capital expenditure limitation, in each case applicable only if Available Liquidity is below a level as may be mutually agreed, and except that the operational covenants will not be applicable to Elk and its subsidiaries until the Merger.

II.    Terms Applicable to All Credit Facilities

Administrative Agent:	DBNY (in such capacity, the "Administrative Agent").
Joint Lead Arrangers and Joint Book Running Managers:	DBSI, Bear Stearns and JPMorgan (in such capacity, the "Lead Arrangers").
Lenders:	DBNY, BSCL and JPMCB and/or a syndicate of lenders arranged by the Lead Arrangers (the "Lenders").
Guaranties:	Each direct and indirect non-borrower domestic subsidiary of BMCA (each, a "Guarantor" and, collectively, the "Guarantors") shall be required to provide an unconditional guaranty of all amounts owing under the Senior Secured Financing (the "Guaranties"), provided that Elk (and its subsidiaries) will not be required to be Guarantors until the consummation of the Merger. Such Guaranties shall be in substantially the same form and substance as provided by the Existing Loan Documents.

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Intercreditor Agreement:	The Administrative Agent for each of the Term Loan Facility and the Revolving Credit Facility will enter into an Intercreditor Agreement to reflect the relative priority of the security interests in the collateral and the related creditor's rights. The intercreditor agreement will contain, among other things, customary agreements between the holders of the obligations under the Revolving Credit Facility, the Term Loan Facility, the 2014 Notes and any untendered 8% Notes due 2007 and 2008 (which will be equally and ratably secured with the 2014 Notes) with respect to (a) the subordination of liens, (b) rights to control the enforcement of remedies with respect to the respective collateral, including standstill periods and release of collateral, (c) the agreement to hold in trust and turn over to the creditors holding a senior lien in the respective collateral any proceeds received from such collateral and (d) agreement not to oppose certain uses of cash collateral or DIP financings.
Incremental Facility:	The Borrower shall be entitled, on one or more occasions, to obtain additional commitments to make and incur loans under the Term Loan Facility or the Revolving Credit Facility in an aggregate principal amount of up to $250 million, subject to substantially the same terms and conditions as provided in the Existing Credit Agreement.
Voluntary Prepayments:	Substantially the same as in the Existing Credit Agreement.
Mandatory Repayments and Commitment Reductions:	Mandatory repayments of Term Loans shall be required from (a) 100% of the proceeds (net of taxes and costs and expenses in connection with the sale) from non-ordinary-course sales of assets which constitute collateral which is subject to a first lien to secure the Term Loans (other than certain assets as may be mutually agreed and subject to reinvestment exceptions as may be mutually agreed), (b) 100% of the net proceeds from issuances of debt (with customary and additional exceptions as may be mutually agreed, including in any event of any refinancing of any bridge financing in respect of the Senior Secured Notes with an issuance of permanent Senior Secured Notes), and (c) 100% of the net proceeds from insurance recovery and condemnation events of the Borrower and its subsidiaries (subject to certain reinvestment rights as may be mutually agreed).

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	All mandatory repayments of Term Loans shall apply to reduce future scheduled amortization payments of the Term Loans being repaid pro rata based upon the then remaining amounts of such payments. To the extent the amount of any mandatory repayment which would otherwise be required as provided above exceeds the aggregate principal amount of Term Loans then outstanding, such excess shall apply to repay advances (but not reduce the commitment) under the Revolving Credit Facility. In addition, (i) if at any time the outstandings pursuant to the Revolving Credit Facility (including Letter of Credit outstandings) exceed the lesser of (x) aggregate commitments with respect thereto or (y) the Borrowing Base, prepayments of Revolving Loans (and/or the cash collateralization of Letters of Credit) shall be required in an amount equal to such excess, and (ii) after giving effect to the consummation of the Merger, all unutilized commitments under the Term Loan Facility (if any) shall be terminated in their entirety, and (iv) 100% of proceeds (net of taxes and costs and expenses in connection with the sale) from non-ordinary-course sales of assets which constitute collateral which is subject to a first lien to secure the Revolving Loans shall be applied to repay advances (but not reduce the Commitment) under the Revolving Credit Facility.
Interest Rates:	At the Borrower's option, Loans may be maintained from time to time as (x) Base Rate Loans, which shall bear interest at the Base Rate in effect from time to time plus the Applicable Margin (as defined below) or (y) Eurodollar Loans, which shall bear interest at the Eurodollar Rate (adjusted for maximum reserves) as determined by the Administrative Agent for the respective interest period plus the Applicable Margin; provided, however, that until the earlier to occur of (i) the 60th day following the Closing Date or (ii) the date upon which the Lead Arrangers shall determine in its sole discretion that the primary syndication of the Credit Facilities has been completed, Eurodollar Loans shall not be permitted to be incurred/Eurodollar Loans shall be restricted to a single one month interest period at all times, with the first such interest period to begin not sooner than 3 business days (nor later than 5 business days) after the Closing Date and with any subsequent interest periods to begin on the last day of the prior one month interest period theretofore in effect.
	"Applicable Margin" shall mean a percentage per annum equal to (w) in the case of Term Loans (A) maintained as Base Rate Loans, 1.75%, and (B) maintained as Eurodollar Loans, 2.75%; and (x) in the case of Revolving Loans (A) maintained as Base Rate Loans, 0.50%, and (B) maintained as Eurodollar Loans, 1.50%; provided, however, that the Applicable Margin for Revolving Loans shall be subject to a leverage based pricing grid.
	"Base Rate" shall mean the higher of (x) the rate that the Administrative Agent announces from time to time as its prime lending rate, as in effect from time to time, and (y) 1/2 of 1% in excess of the overnight federal funds rate.

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	Interest periods of 1, 2, 3 and 6 months or, to the extent agreed to by all respective Lenders with commitments and/or Loans under a given tranche of the Credit Facilities, 9 or 12 months, shall be available in the case of Eurodollar Loans.
	The Credit Facilities shall include customary protective provisions for such matters as defaulting banks, capital adequacy, increased costs, reserves, funding losses, illegality and withholding taxes. The Borrower shall have the right to replace any Lender that (i) charges a material amount in excess of that being charged by the other respective Lenders with respect to contingencies described in the immediately preceding sentence or (ii) refuses to consent to certain amendments or waivers of the respective Senior Secured Financing which expressly require the consent of such Lender and which have been approved by the respective Required Lenders.
	Interest in respect of Base Rate Loans shall be payable quarterly in arrears on the last business day of each calendar quarter. Interest in respect of Eurodollar Loans shall be payable in arrears at the end of the applicable interest period and every three months in the case of interest periods in excess of three months. Interest will also be payable at the time of repayment of any Loans and at maturity. All interest on Base Rate Loans, Eurodollar Loans and commitment fees and any other fees shall be based on a 360 day year and actual days elapsed (or, in the case of Base Rate Loans determined by reference to the prime lending rate, a 365/366 day year and actual days elapsed).
Default Interest:	Overdue principal, interest and other amounts shall bear interest at a rate per annum equal to the greater of (i) the rate which is 2% in excess of the rate otherwise applicable to Base Rate Loans of the respective tranche under the Senior Secured Financing from time to time and (ii) the rate which is 2% in excess of the rate then borne by such borrowings. Such interest shall be payable on demand.
Agent/Lender Fees:	The Administrative Agent, the Lead Arrangers and the Lenders shall receive such fees as have been separately agreed upon.

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Assignments and Participations:
The Borrower may not assign its rights or obligations under the Senior Secured Financing. Any Lender may assign, and may sell participations in, its rights and obligations under the Senior Secured Financing, subject (x) in the case of participations, to customary restrictions on the voting rights of the participants and (y) in the case of assignments, to such limitations as may be established by the Administrative Agent (including (i) a minimum assignment amount as may be mutually agreed (or, if less, the entire amount of such assignor's commitments and outstanding Loans at such time), (ii) an assignment fee in the amount of $3,500 to be paid by the respective assignor or assignee to the Administrative Agent and (iii) the receipt of the consent of the Administrative Agent (not to be unreasonably withheld or delayed)). The Senior Secured Financing shall provide for a mechanism which will allow for each assignee to become a direct signatory to the Senior Secured Financing and will relieve the assigning Lender of its obligations with respect to the assigned portion of its commitment. Except during the continuance of a Default, the consent of the Borrower will be required for an assignment, which consent will not be unreasonably withheld.

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Waivers and Amendments:

Amendments and waivers of the provisions of the loan documentation will require the approval of Lenders holding commitments and/or outstandings (as appropriate) representing more than 50% of the aggregate commitments and outstandings under the Term Loan Facility or the Revolving Credit Facility, as the case may be (the "Required Lenders"), except that (a) the consent of each Lender affected thereby will be required with respect to (i) increases in commitment amounts, (ii) reductions of principal, interest or fees and (iii) extensions of final scheduled maturities or times for payment of interest or fees, (b) the consent of all of the Lenders shall be required with respect to releases of all or substantially all of the collateral, and (c) the approval of Lenders holding commitments representing more than 662/3% of the aggregate commitments under the Revolving Credit Facility will be required with respect to any changes to the Borrowing Base (or the definitions therein) which would result in an increase in availability thereunder; provided, however, that if any of the matters described in clause (a) or (b) above is agreed to by the Required Lenders, the Borrower shall have the right to either (x) substitute any non consenting Lender by having its Loans and commitments assigned, at par, to one or more other institutions, subject to the assignment provisions described above, or (y) with the consent of the Required Lenders, terminate the commitment of any non consenting Lender, subject to repayment in full of all obligations of the Borrower owed to such Lender relating to the Loans and participations held by such Lender.

Documentation; Governing Law:

The Lenders' commitments for the Senior Secured Financing will be subject to the negotiation, execution and delivery of definitive financing agreements (and related security documentation, guaranties, etc.) consistent with the terms of this Term Sheet, in each case prepared by Shearman & Sterling LLP as counsel to the Administrative Agent, and satisfactory to the Administrative Agent and the Lenders (including, without limitation, as to the terms, conditions, representations, covenants and events of default contained therein); provided, however, that except as expressly provided herein, such definitive financing agreements will be in substantially the same form and substance as the Existing Loan Documents. All documentation shall be governed by the internal law of the State of New York (except security documentation that should be governed by local law).

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Conditions Precedent:
A.	To Tranche I and the Initial Loans under the Revolving Credit Facility
1.	Except for the funding of the Credit Facilities, the Tender Offer shall have been consummated (or will be concurrently consummated) in accordance in all material respects with the documentation therefor and all applicable law and will result with the Purchaser owning sufficient shares of Common Stock to enable it, voting without any other shareholders of Elk (other than HIA), to approve the Merger (but in any event not less than a majority of such shares). Elk shall not have in effect any "poison pills" or other shareholder rights which would materially increase the cost of the Tender Offer or materially adversely effect the ability of the Purchaser to consummate the Merger no later than the Tranche II Final Funding Date.
2.	The Refinancing with respect to the indebtedness of BMCA shall have been consummated to the reasonable satisfaction of the Lead Arrangers.
3.	The Borrower shall have received gross cash proceeds of at least $325 million (calculated before underwriting fees) from the issuance of the Senior Secured Notes (or the bridge loan) and shall have used all such cash proceeds to make payments owing in connection with the Transaction before utilizing any proceeds of Loans for such purpose.
4.	After giving effect to the consummation of the Tender Offer, BMCA and its subsidiaries (other than Elk and its subsidiaries) shall have no outstanding indebtedness or material contingent liabilities, except for indebtedness incurred pursuant to the (i) Senior Secured Notes (or the Bridge Loans), (ii) the Senior Secured Financing, (iii) the 2014 Notes, (iv) such other existing indebtedness and contingent liabilities permitted under the Existing Credit Agreement and (v) such additional indebtedness and contingent liabilities as shall be permitted by the Operative Documents (the "Existing Indebtedness").
5.	There not occurring any condition or circumstance which has had, or could reasonably be expected to have a Material Adverse Effect.
6.	All costs, fees, expenses (including, without limitation, legal fees and expenses) and other compensation contemplated hereby, payable to the Lead Arrangers and the Lenders or otherwise payable in respect of the Transaction shall have been paid to the extent due.

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7.	The Guaranties shall have been executed and be in full force and effect and all Security Agreements, documents and instruments required to perfect the Agent's security interest in the Collateral shall have been executed and delivered and, if applicable, be in proper form for filing, and none of the Collateral shall be subject to any other pledges, security interest or mortgages, except for liens permitted under the Operative Documents; provided, however that with respect to any collateral (other than the pledge and perfection of the security interests in the capital stock of subsidiaries held by the Borrower and the Guarantors and other assets pursuant to which a lien may be perfected by the filing of a financing statement under the Uniform Commercial Code), the security interest in which may not be perfected by the filing of a UCC financing statement, if the perfection of Agent's security interest in such collateral may not be accomplished prior to the Closing Date without undue burden or expense and without the taking of any action that goes beyond commercial reasonableness, then the delivery of documents and instruments for perfection of such security interests shall not constitute a condition precedent to the initial borrowings under the Credit Facilities, if the Borrower agrees to deliver or cause to he delivered such documents and instruments, and take or cause to he taken such other actions as may be required to perfect such security interests within a mutually agreed period of time after the Closing Date.
8.	The respective Lenders shall have received (x) customary legal opinions from counsel (including, without limitation, New York counsel) reasonably acceptable to the Administrative Agent and (y) a solvency certificate, in the same form and substance as provided under the Existing Credit Agreement, from the chief financial officer of BMCA.
9.	The Senior Secured Financing shall have obtained ratings (of any level) from Standard & Poor's Ratings Services and Moody's Investor's Services, Inc., which ratings shall be in effect on the Closing Date.
B.	To Tranche II:
1.	Except for the funding of Tranche II, the Merger shall have been consummated (or will be concurrently consummated) in accordance in all material respects with the documentation therefor (including any proxy statement) and all applicable law.
2.	After giving effect to the consummation of the Merger, Elk and its subsidiaries shall have no outstanding indebtedness or contingent liabilities except as permitted by the documentation for the Operative Documents.
3.	There shall not exist any judgment, order, injunction or other restraint prohibiting or imposing materially adverse conditions upon the Merger or the transactions contemplated by the Operative Documents.
4.	All costs, fees, expenses (including, without limitation, legal fees and expenses) and other compensation contemplated hereby, payable to the Lead Arrangers and the Lenders or otherwise payable in respect of the Merger shall have been paid to the extent due.

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C.	To All Loans and Letters of Credit:
1.	All representations and warranties shall be true and correct in all material respects on and as of the date of each borrowing of a Loan and each issuance of a Letter of Credit (although any representations and warranties which expressly relate to a given date or period shall be required to be true and correct in all material respects as of the respective date or for the respective period, as the case may be), before and after giving effect to such borrowing or issuance and to the application of the proceeds therefrom, as though made on and as of such date
2.	No Default under the Credit Facilities or event which with the giving of notice or lapse of time or both would be a Default under the Credit Facilities, shall have occurred and be continuing, or would result from any borrowing of a Loan or issuance of a Letter of Credit.

Representations and Warranties:	Substantially the same as in the Existing Loan Documents.
Events of Default:	Substantially the same as in the Existing Loan Documents.
Indemnification:	Substantially the same as in the Existing Loan Documents.

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EX-99.(B)(2)

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Exhibit (b)(2)

DEUTSCHE BANK AG
CAYMAN ISLAND
BRANCH
60 Wall Street
New York, NY 10005 BEAR STEARNS
CORPORATE
LENDING INC.
383 Madison Avenue
New York, NY 10179 JPMORGAN CHASE
BANK, N.A.
270 Park Avenue
New York, NY 10017

January 17, 2007

Building Materials Corporation of America,
BMCA Acquisition Inc. and
BMCA Acquisition Sub Inc.
1361 Alps Road
Wayne, New Jersey 07470

Attention: John Maitner

Re: Bridge Commitment Letter

Ladies and Gentlemen:

        We understand that BMCA Acquisition Sub Inc. (the "Purchaser"), a direct wholly-owned subsidiary of BMCA Acquisition Inc. and an indirect wholly-owned subsidiary of Building Materials Corporation of America ("BMCA") intends to offer to acquire through a tender offer (the "Tender Offer") for up to $42 in cash per share all of the outstanding shares (and associated Series A Participating Preference Stock Rights) of the common stock, $1.00 par value (the "Company Stock"), of ElkCorp, a Delaware corporation ("Elk"), but in any event not less than sufficient shares of Company Stock to enable the Purchaser—voting without any other shareholders of Elk, (other than Heyman Investment Associates Limited Partnership ("HIA") which has agreed to sell to you at its cost its shares of Elk) to approve a merger of the Purchaser with Elk, and that as soon a practicable after the closing of the Tender Offer (the "Closing Date"), the Purchaser will consummate a merger with Elk (the "Merger" and, together with the Tender Offer, the "Acquisition"). We further understand that the funding requirements for the Acquisition (including related fees and expenses) and the refinancing and/or redemption (the "Refinancing") of certain of the outstanding indebtedness of BMCA and Elk, together with ongoing working capital needs, will be met from the proceeds of (i) a term loan facility (the "Term Loan Facility") of up to $950 million to be drawn in two tranches, the first on the Closing Date and the second on the closing of the Merger, (ii) a revolving credit facility (the "Revolving Credit Facility" and, together with the Term Loan Facility, the "Bank Financing") of up to $600 million (of which up to $150 million (plus seasonal working capital requirement) or such greater amount as may be mutually agreed will be drawn on the Closing Date), and (iii) either the Bridge Loan (as defined below) or the issuance and sale of the Debt Securities (as defined below). The Acquisition, the Refinancing, the Bank Financing, the Bridge Loan and the issuance and sale of the Debt Securities are herein collectively referred to as the "Transaction".¹

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We also understand that, in accordance with the terms of the Bank Financing, you may elect, at or price to the Merger, to increase the Revolving Credit Facility by up to $100 million provided that the Term Loan Facility is reduced by an equal amount.

        In connection with the Transaction, you have engaged one or more investment banks satisfactory to the Lenders (the "Take Out Banks") to sell or place senior secured debt securities (the "Debt Securities").

        You have requested that Deutsche Bank AG Cayman Islands Branch ("DB Cayman"), Bear Stearns Corporate Lending Inc. ("BSCL") and JPMorgan Chase Bank, N.A. ("JPMCB" and together with DB Cayman and BSCL, collectively, the "Lenders") commit to provide funds in the aggregate amount of up to $325 million in the form of a senior secured bridge loan to be made available as described in Section 1 hereof (the "Bridge Loan").

        Bridge Loan. Subject to the terms and conditions hereof and in the Summary Term Sheet attached hereto as Exhibit A (the "Term Sheet" and together with this letter, collectively, the "Bridge Commitment Letter"), (a) DB Cayman is pleased to confirm its several and not joint commitment to provide 50% of the Bridge Loan on the Closing Date, (b) BSCL is pleased to confirm its several and not joint commitment to provide 35% of the Bridge Loan on the Closing Date and (c) JPMCB is pleased to confirm its several and not joint commitment to provide 15% of the Bridge Loan on the Closing Date. The proceeds of the Bridge Loan shall be used solely to finance the Tender Offer, the Refinancing and to pay fees and expenses incurred in connection therewith. The principal terms of the Bridge Loan are summarized in the Term Sheet.

        DB Cayman and BSCL are pleased to confirm that they, or one of their respective affiliates, will act as a Joint Lead Arrangers and Joint Book Running Managers for the Bridge Loan. JPMCB is pleased to confirm that it, or one of its affiliates, will act as a Joint Book Running Manager for the Bridge Loan. It being understood and agreed that the DB Cayman name or its affiliate's name shall appear to the left of BSCL or its affiliates and that the BSCL name or its affiliates name shall appear immediately above or immediately to the left of JPMCB on the offering documents.

        Unless the Lenders' commitments hereunder shall have been terminated pursuant to Section 7, the Lenders shall have the exclusive right to provide the Bridge Loan or other bridge or interim financing required in connection with the Transaction.

        You represent, warrant and covenant that (i) no written information, other than business and financial projections, budgets, pro forma data and forecasts, that has been or is hereafter furnished by you or on your behalf to the Lenders connection with Transaction and (ii) no other information given to the Lenders and supplied or approved by you or on your behalf (such written information and other information being referred to herein collectively as the "Information") taken as a whole contained (or, in the case of Information furnished after the date hereof, will contain), as of the time it was (or hereafter is) furnished, any material misstatement of fact or omitted (or will omit) as of such time to state any material fact necessary to make the statements therein taken as a whole not misleading, in the light of the circumstances under which they were (or hereafter are) made; provided that, with respect to Elk and its subsidiaries, the foregoing representation is limited to your best knowledge. With respect to business and financial projections, budgets, pro forma data and forecasts, if any (collectively, the "Projections"), that have been or will be prepared by you or on your behalf and has been or is hereafter furnished by you or on your behalf to the Lenders in connection with Transaction, no representation, warranty or covenant is made other than that the Projections have been (and, in the case of Projections furnished after the date hereof, will be) prepared in good faith based on assumptions believed to be reasonable at the time of preparation thereof (it being understood that such Projections are subject to significant uncertainties and contingencies, many of which are beyond the Company's control, and that no assurance can be given that the Projections will be realized). You agree to supplement the Information and the Projections from time to time until the date of the initial borrowing under the Senior Secured Financing, as appropriate, so that the representations and warranties in the preceding sentence remain correct. In arranging and syndicating the Bridge Loans, the Lenders will be using and relying on the Information and the Projections.

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        Financing Documentation. The making of the Bridge Loan will be governed by definitive loan or note purchase and related agreements and other relevant documentation (collectively, the "Financing Documentation") in form and substance reasonably satisfactory to the Lenders and to you. The Financing Documentation shall be prepared by Shearman & Sterling LLP, special counsel to the Lenders and shall contain such covenants, terms and conditions consistent with this Bridge Commitment Letter.

        Conditions. The obligation of each Lender under Section 1 of this Bridge Commitment Letter to provide its portion of the Bridge Loan is subject to fulfillment of the conditions set forth in the commitment letter (including the term sheets attached thereto) relating to the Bank Financing of even date herewith for which Deutsche Bank Securities Inc. ("DBSI"), Bear, Stearns & Co. Inc. ("Bear Stearns") and J.P. Morgan Securities Inc. ("JPMorgan") and/or their respective designated affiliates are acting as a lead arranger (provided that the Lenders shall (separately from the agent(s) in respect of the Bank Financing) have the right to confirm compliance with, and/or to waive compliance with, all such conditions precedent) and the following additional conditions:

        Financing Documentation. BMCA, the Purchaser and BMCA Acquisition Inc. and the Lenders shall have entered into the Financing Documentation relating to the Bridge Loan and the transactions contemplated thereby incorporating the terms and conditions outlined in this Bridge Commitment Letter.

        Bank Financing. BMCA, the Purchaser and BMCA Acquisition Inc. shall have obtained the Bank Financing (collectively with all documents and instruments related thereto or delivered in connection therewith, the "Bank Documents"). The Bank Documents shall be in full force and effect and the parties thereto shall be in compliance with all material agreements thereunder.

        Take Out Banks. You shall have engaged the Take Out Banks to publicly offer or privately place the Debt Securities, the proceeds of which will be used to fund either the Tender Offer and the Refinancing or to prepay in whole or in part the Bridge Loan. You shall have prepared offering memoranda relating to the issuance of the Debt Securities (which offering memoranda shall contain audited, unaudited and pro forma financial statements meeting the requirements (except with respect to Rule 3-10) of Regulation S X under the Securities Act of 1933, as amended, of you and Elk (provided that with respect to Elk and its subsidiaries, such pro forma information shall be based on the publicly available information of Elk and its subsidiaries), as applicable, for the periods required of a registrant on Form S 1) and the Take Out Banks shall have been afforded the opportunity to market such Debt Securities pursuant to such offering memoranda. You shall have used your commercial reasonable efforts to assist the Take Out Banks in marketing the Debt Securities, including, without limitation, having prepared the offering memorandum relating thereto, having made your senior management and other appropriate representatives available (at mutually agreeable times) to participate in meetings with prospective investors and having provided such information and assistance as the Take Out Banks shall have reasonably requested during the course of such marketing process.

        Indemnification and Contribution. You agree to indemnify each Lender, each entity to which such Lender syndicates or assigns any portion of its commitment hereunder pursuant to Section 8 hereof and each of their respective affiliates and their respective officers, directors, employees, agents, representatives and control persons to the extent set forth in Annex I hereto, which annex is incorporated by reference herein and constitutes a part hereof.

        Expenses. In addition to any fees that may be payable to the Lenders hereunder and regardless of whether any of the transactions contemplated by this Bridge Commitment Letter are consummated, if this Bridge Commitment Letter is terminated, the Bridge Loan is made available or the Financing Documentation is executed and delivered, you hereby agree to reimburse the Lenders for all reasonable fees and disbursements of legal counsel, including but not limited to the reasonable fees and disbursements of Shearman & Sterling LLP, the Lenders' special counsel, and all of the Lenders' travel

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and other reasonable out of pocket expenses incurred in connection with the Transaction or otherwise arising out of the Lenders' commitments hereunder.

        Termination. Each Lender's commitment hereunder to provide the Bridge Loan shall terminate, unless expressly agreed to by such Lender in its sole discretion to be extended to another date, on the earlier of (A) June 30, 2007 if no portion of the Bridge Loan has been funded (other than as a result of failure of such Lender to fulfill their respective obligations hereunder), and (B) the date on which BMCA shall have informed such Lender that it has decided not to proceed with the Transaction. No such termination of such commitment shall affect your obligations under Sections 5 and 6 hereof or this Section 7, which shall survive any such termination.

        Assignment; Syndication. This Bridge Commitment Letter shall not be assignable by any party hereto without the prior written consent of the other parties (other than, in the case of either Lender, to an affiliate of such Lender, it being understood that any such affiliate shall be subject to the restrictions set forth in this Section 8); provided, however, that the Lenders shall have the right, in their sole discretion, to syndicate the Bridge Loan and their respective commitments with respect thereto among banks or other financial institutions pursuant to the Financing Documentation or otherwise and to sell, transfer or assign all or any portion of, or interests or participations in, the Bridge Loan and their respective commitments with respect thereto and any notes issued in connection therewith. You agree to use your commercially reasonable efforts, whether prior to or after the Closing Date, to assist the Lenders in syndicating the Bridge Loan or their commitments with respect thereto, including, without limitation, in connection with (x) the preparation of an information package regarding the Transaction, including the Information and the Projections described in Section 1 hereof, and (y) meetings and other communications with prospective lenders, including making your senior management and other appropriate representatives available (at mutually agreeable times) to participate in such meetings.

        Miscellaneous. THIS BRIDGE COMMITMENT LETTER SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK, AND ANY RIGHT TO TRIAL BY JURY WITH RESPECT TO ANY CLAIM, ACTION, SUIT OR PROCEEDING ARISING OUT OF OR CONTEMPLATED BY THIS COMMITMENT LETTER IS HEREBY WAIVED. YOU HEREBY SUBMIT TO THE NON EXCLUSIVE JURISDICTION OF THE FEDERAL AND NEW YORK STATE COURTS LOCATED IN THE CITY OF NEW YORK IN CONNECTION WITH ANY DISPUTE RELATED TO THIS COMMITMENT LETTER OR ANY MATTERS CONTEMPLATED HEREBY. This Bridge Commitment Letter embodies the entire agreement and understanding between you and the Lenders. The Bridge Commitment supersedes all prior agreements and understandings relating to the subject matter hereof. This Bridge Commitment Letter may be executed in any number of counterparts, each of which shall be an original, but all of which shall constitute one instrument.

        Each Lender reserves the right to employ the services of its affiliates (including, in the case of DB Cayman, DBSI and, in the case of BSCL, Bear Stearns and, in the case of JPMCB, JPMorgan) in providing services contemplated by this Bridge Commitment Letter and to allocate, in whole or in part, to its affiliates certain fees payable to such Lender in such manner as such Lender and its affiliates may agree in their sole discretion. You acknowledge that (i) each Lender may share with any of its affiliates (including, in the case of DB Cayman, DBSI and, in the case of BSCL, Bear Stearns and, in the case of JPMCB, JPMorgan) and such affiliates may share with such Lender (in each case, subject to any confidentiality agreements applicable thereto), any information related to you or your affiliates, Elk (including information relating to creditworthiness) or the Transaction, (ii) the Lenders and their affiliates may be providing debt financing, equity capital, financial advisory or other services (including financial advisory services to you, Elk and their respective affiliates) to other companies in respect of which you or Elk may have conflicting interests regarding the transactions described herein and otherwise and (iii) this Bridge Commitment Letter is not intended to create a fiduciary relationship among the parties hereto.

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        This Bridge Commitment Letter is furnished for your benefit, and may not be relied upon by any other person or entity. Except as otherwise agreed in writing between us, you agree that this Bridge Commitment Letter is for your confidential use only and that neither its existence nor the terms hereof will be disclosed by you to any person other than your officers, directors, employees, accountants, attorneys and other advisors, and then only on a "need to know" basis in connection with the transactions contemplated hereby and on a confidential basis. Notwithstanding the foregoing, following your acceptance of the provisions hereof and your return of an executed counterpart of this Bridge Commitment Letter to us as provided below, (i) you shall be permitted to furnish a copy hereof to Elk and its advisors in connection with the proposed Acquisition, (ii) you may make public disclosure of the existence and amount of the commitments hereunder and of the identity of the Lenders, (iii) you may file a copy of this Bridge Commitment Letter in any public record in which it is required by law to be filed and (iv) you may make such other public disclosure of the terms and conditions hereof as, and to the extent, you believe in good faith, after consulting with counsel, is required by law or in connection with complying with a court order. Except as otherwise required by law or unless the Lenders have otherwise consented, you are not authorized prior to your acceptance of this Bridge Commitment Letter as provided below to show or circulate this Bridge Commitment Letter to any other person or entity (other than your legal or financial advisors in connection with your evaluation hereof).

        If you are in agreement with the foregoing, please sign and return to the Lenders the enclosed copy of this Bridge Commitment Letter no later than 5:00 p.m., New York time, on January 31, 2007, whereupon the undertakings of the parties shall become effective to the extent and in the manner provided hereby. This offer shall terminate if not so accepted by you on or prior to that time.

Very truly yours,
DEUTSCHE BANK AG CAYMAN ISLANDS BRANCH
By:	/s/   ALBERT FISCHETTI Name: Albert Fischetti Title: Director
By:	/s/  STEPHEN CAYER Name: Stephen Cayer Title: Director

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BEAR STEARNS CORPORATE LENDING INC.
By:	/s/  LAWRENCE B. ALLETTO Name: Lawrence B. Alletto Title: Vice President

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JPMORGAN CHASE BANK, N.A.
By:	/s/  THOMAS H. KOZLARK Name: Thomas H. Kozlark Title: Vice President

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Accepted and Agreed to as of the date first above written:

BUILDING MATERIALS CORPORATION OF AMERICA
By:	/s/  JOHN M. MAITNER Name: John M. Maitner Title: Vice President and Treasurer
BMCA ACQUISITION INC.
By:	/s/  JOHN M. MAITNER Name: John M. Maitner Title: Vice President and Treasurer
BMCA ACQUISITION SUB INC.
By:	/s/  JOHN M. MAITNER Name: John M. Maitner Title: Vice President and Treasurer

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EXHIBIT A

Bridge Loan and Term Loan Facility
Summary Term Sheet^b

Borrower:	Building Materials Corporation of America ("BMCA"), BMCA Acquisition Inc. and BMCA Acquisition Sub Inc. (collectively, the "Borrower").
Guarantors:	All obligations under the Bridge Loan shall be unconditionally guaranteed on a senior basis by each of BMCA's subsidiaries that guarantee or are borrowers under the Bank Financing (collectively, the "Guarantors").
Lenders:	Deutsche Bank AG Cayman Islands Branch, Bear Stearns Corporate Lending Inc. and JPMorgan Chase Bank, N.A.
Administrative Agent:	Deutsche Bank AG Cayman Islands Branch (or a designee thereof)
Amount:	$325 million senior secured bridge loan (the "Bridge Loan").
Maturity:	Any outstanding amount under the Bridge Loan will be required to be repaid in full on the earlier of (a) one year following the initial funding date of the Bridge Loan and (b) the closing date of any permanent financing; provided, however, that if the Borrower has failed to raise permanent financing before the date set forth in (a) above, the Bridge Loan shall be converted, subject to the conditions outlined under "Conditions to Conversion of the Bridge Loan", to a senior term loan facility (the "Term Loan") with a maturity of eight years after the Closing Date; provided, further, however, that the Borrower shall pay to the Lenders on the Conversion Date (as defined below), a conversion cash fee equal to 1.75% of the principal amount of the Term Loan then outstanding (the "Conversion Fee"), subject to the Conversion Fee Rebate (as defined below).

^b

Capitalized terms used herein and not defined herein shall have the meanings provided in the bridge commitment letter to which this summary term sheet is attached.

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The Conversion Fee Rebate shall mean the obligation of the Lenders to rebate the Applicable Percentage of the Conversion Fee to the extent the Term Loan is repaid in full with the proceeds of Debt Securities within the time frames set forth below after the repayment thereof (it being agreed that if the Bridge Loan is partially repaid, such rebates will be reduced pro rata to the portion of the Term Loan so repaid):

Number of Days	Applicable Percentage
0-90	75%
91-150	50%
151-210	25%
Thereafter	0%

Commitments, Funding and Other Fees:

(i) a cash fee of 0.50% of the total amount committed shall be earned by the Lenders, to be allocated pro rata between the Lenders based on their respective commitments, upon execution of the Bridge Commitment Letter and be due and payable upon the Closing Date (it being understood that no fee is payable under this clause (i) if the Closing Date does not occur); and (ii) on the date of funding of the Bridge Loan (the "Funding Date"), the Borrower shall pay a cash fee (the "Funding Fee") to the Lenders, to be allocated pro rata between the Lenders based on their respective commitments, equal to 1.25% of the aggregate principal amount of the Bridge Loan funded on the Funding Date, subject to the Funding Fee Rebate (as defined below).

The Funding Fee Rebate shall mean the obligation of the Lenders to rebate the Applicable Percentage of the Funding Fee to the extent the Bridge Loan is repaid in full with the proceeds of Debt Securities within the time frames set forth below after the repayment thereof (it being agreed that if the Bridge Loan is partially repaid, such rebates will be reduced pro rata to the portion of the Bridge Loan so repaid):

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Number of Days	Applicable Percentage
0-30	100%
31-90	75%
91-150	50%
151-210	25%
Thereafter	0%

Use of Proceeds:	To fund in part the Tender Offer and the Refinancing and to pay related fees and expenses.
Interest Rate:	The Bridge Loan and the Term Loan, as applicable, shall bear interest, reset monthly, at the rate of the three month LIBOR plus 4.25% per annum (the "Interest Rate") and such spread (the "Spread") over LIBOR shall automatically increase by 0.5% on the three (3) month anniversary of the Closing Date and for each period of three months (or portion thereof) thereafter that the Bridge Loan or the Term Loan, as the case may be, is outstanding; provided, however, that the interest rate determined in accordance with the foregoing shall not exceed 11.25% per annum (the "Fixed Rate") at any time. At any time on or after the date the Borrower converts the Bridge Loan to the Term Loan (the "Conversion Date"), the Term Loan shall initially bear interest rate per annum equal to the interest rate per annum then in effect with respect to the Bridge Loan.
	Interest on the Bridge Loan and the Term Loan shall be payable on a quarterly basis; provided, however, that at such time as the Term Loan bears interest at the Fixed Rate, interest shall be payable on a semi annual basis.

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Security:

All amounts owing in respect of the Bridge Loan and the Term Loan will be secured by a perfected second priority security interest (subject to permitted liens) in all of the assets and property which constitute collateral for the Term Loan Facility and a perfected third priority security interest (subject to permitted liens) in all of the assets and property which constitute collateral for the Revolving Credit Facility. To the extent applicable, the liens securing the Bridge Loan and the Term Loan will be junior and subordinate to the liens securing the Revolving Credit Facility, the Term Loan Facility and BMCA's 7.75% Notes due 2014 (the "2014 Notes") and BMCA's untendered 8% Notes due 2007 and 2008. The priority of the security interests in the collateral and related creditors' rights will be set forth in an intercreditor agreement in form and substance satisfactory to the Borrower, the Administrative Agent under the Revolving Credit Facility, the Administrative Agent under the Term Loan Facility, the Lenders and the trustee under the indenture governing the 2014 Notes (the "2014 Indenture"). The intercreditor agreement will contain, among other things, customary agreements between the holders of the obligations under the Revolving Credit Facility, the Term Loan Facility, the 2014 Notes and the Lenders with respect to (i) the subordination of the liens securing the Bridge Loan, the Term Loan, (ii) the respective rights of the holders of obligations under the Revolving Credit Facility, the Term Loan Facility and the 2014 Notes to control the enforcement of remedies with respect to collateral, subject to a standstill period as may be mutually agreed, and to control the release of collateral, (iii) the agreement of the Lenders to hold in trust and turnover to the holders of the obligations under the Revolving Credit Facility, the Term Loan Facility and the 2014 Notes proceeds received from collateral and (iv) the agreement of the Lenders not to oppose certain uses of cash collateral or DIP financings unless the holders of obligations under the Revolving Credit Facility and under the Term Loan Facility have opposed such uses of cash collateral or DIP financings.

Ranking:

The obligations of the Borrower and the Guarantors under the Bridge Loan will be senior obligations of the Borrower and the Guarantors and will rank (i) equal in right of payment to all senior indebtedness of the Borrower or such Guarantor, as the case may be, and (ii) senior to any subordinated indebtedness of the Borrower or such Guarantor, as the case may be.

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Optional Prepayment:	The Borrower may prepay the Bridge Loan or the Term Loan, in whole or in part, at any time at a redemption price equal to 100% of the principal amount thereof plus accrued interest thereon; provided, however, that to the extent the Bridge Loan is refinanced other than with the proceeds of Debt Securities, the Lenders shall be entitled to a redemption fee equal to 1.75% of the principal amount of the Bridge Loan so refinanced; provided, further, that at such time as the Term Loan bears interest at the Fixed Rate, the Term Loan shall be subject to redemption restrictions and premiums typical for high yield debt securities. No such optional prepayment shall be made without the consent of the Lenders, unless all amounts owing are paid in full.
Mandatory Prepayment:	Net proceeds of sales of debt securities or equity securities, in a public offering or private placement by the Borrower or any of its subsidiaries, and the net proceeds of asset sales shall be used to prepay the Bridge Loan plus accrued interest and any other amount payable thereunder to the full extent of the net proceeds so received to the extent such net proceeds are not required to retire the Bank Financing or any replacement or refinancing thereof. The Borrower will be required to make an offer to purchase all notes outstanding under the Bridge Loan or the Term Loan, as the case may be, upon the occurrence of a Change of Control (to be defined) in a manner reasonably acceptable to the Lenders and the Borrower.
Participation/Assignment or Syndication:	The Lenders may participate out or sell or assign, or syndicate to other lenders, the Bridge Loan or the Term Loan, in whole or in part, at any time, subject to compliance with applicable securities laws.

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Conditions to Conversion of the Bridge Loan:	One year after the Funding Date of any portion of the Bridge Loan, unless (A) the Borrower or any significant subsidiary thereof is subject to a bankruptcy or other insolvency proceeding, (B) there exists a payment default (whether or not matured) with respect to the Bridge Loan or the Conversion Fee or (C) there exists a default in the payment when due at final maturity of any indebtedness (excluding the indebtedness under the Bridge Loan) of the Borrower or any of its subsidiaries in excess of an amount as may be mutually agreed upon for any such default or all such defaults, or the maturity of such indebtedness shall have been accelerated, the Bridge Loan shall convert into the Term Loan; provided, however, that if an event described in clause (B) or (C) is continuing at the scheduled Conversion Date but the applicable grace period, if any, set forth in the events of default provision of the Bridge Loan has not expired, the Conversion Date shall be deferred until the earlier to occur of (i) the cure of such event or (ii) the expiration of any applicable grace period.
Debt Security Exchange:	The Lenders may at any time after the Conversion Date require that the Borrower exchange the Term Loan for long term notes which shall bear interest at the Fixed Rate, determined at such time, shall not be prepayable (subject to customary provisions relating to equity claw-back of up to 35%) for three years from the Conversion Date and shall have such other similar terms and conditions as contained in the 2014 Indenture (with such additional carve-outs, exceptions and increased baskets as may be mutually agreed) and shall provide customary registration rights, including, without limitation, a registered exchange offer or, if not permitted by applicable law to effect an exchange offer, demand registrations.
Covenants:	The Financing Documentation are expected to contain substantially the same affirmative and negative covenants as those in the 2014 Indenture (with carve-outs as provided in such indenture and with such other carve outs, exceptions and increased baskets as may be mutually agreed). Further, during the term of the Bridge Loan, it is expected that the covenants will be more restrictive than the covenants applicable to the Term Loan and will include additional prohibitive covenants relating to asset sales, certain acquisitions, certain debt incurrences and certain other corporate transactions as are customary for such financings.
Representations and Warranties:	Substantially the same as provided in the Term Loan Facility.
Conditions Precedent:	As set forth in Section 3 of the Bridge Commitment Letter.

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Events of Default:	Substantially the same as provided in the 2014 Indenture, subject to, in certain cases, notice and grace provisions as provided in the 2014 Indenture and additional notice and grace provisions as may be mutually agreed.
Governing Law and Forum:	The State of New York.
Indemnification and Expense Reimbursement:	Customary for transactions of this type.

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Annex I

        In connection with the Bridge Commitment Letter to which this Annex I is attached (the "Agreement"):

        You hereby agree to indemnify and hold harmless each Lender and each entity to which such Lender syndicates or assigns any portion of its commitment under the Agreement pursuant to Section 8 of the Agreement and their respective affiliates and their respective directors, officers, partners, employees, agents, representatives and control persons (collectively, the "Indemnified Persons") from and against any losses, claims, damages, liabilities or expenses incurred by them (including reasonable fees and disbursements of counsel) which (i) are related to or arise out of (A) actions taken or omitted to be taken (including any untrue statements made or any statements omitted to be made) by you or (B) actions taken or omitted to be taken by an Indemnified Person with your consent or in conformity with your actions or omissions or (ii) are otherwise related to or arise out of or in connection with, in each case, the proposed transactions giving rise to or contemplated by the Agreement, including modifications or future additions to the Agreement, or execution of letter agreements or other related activities, and to promptly reimburse each Lender and any other Indemnified Person for all expenses (including reasonable fees and disbursements of counsel) as incurred by such Lender or any such Indemnified Person in connection with investigating, preparing or defending any such action or claim, whether or not in connection with pending or threatened litigation in which such Lender or any other Indemnified Person is a party. You will not, however, be responsible for any losses, claims, damages, liabilities or expenses of any Indemnified Person pursuant to clause (ii) of the preceding sentence to the extent the same resulted from the gross negligence, bad faith or willful misconduct of such Indemnified Person (as determined by a proceeding in a court of competent jurisdiction). You also agree that if any indemnification sought by an Indemnified Person pursuant to the Agreement is unavailable or insufficient, for any reason, to hold harmless the Indemnified Persons in respect of any losses, claims, damages or liabilities (or actions in respect thereof), then (whether or not such Lender is the Indemnified Person) you and such Lender, in order to provide for just and equitable contribution, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, liabilities, damages and expenses (or actions in respect thereof) in such proportion as is appropriate to reflect (i) the relative benefits received by you on the one hand and such Lender and the Indemnified Person on the other hand from the actual or proposed transactions giving rise to or contemplated by the Agreement or (ii) if the allocation provided by the foregoing clause (i) is not permitted by applicable law, not only such relative benefits but also the relative fault of you on the one hand and such Lender and the Indemnified Person on the other, in connection with the statements or omissions or alleged statements or omissions that resulted in such losses, claims, damages, liabilities or expenses (or actions in respect thereof), as well as any other relevant equitable considerations; provided that in any event the aggregate contribution of such Lender and the other Indemnified Persons to all losses, claims, damages, liabilities and expenses with respect to which contributions are avail able hereunder will not exceed the amount of fees actually received by such Lender from you pursuant to the proposed transactions giving rise to the Agreement. For purposes of determining the relative benefits to you on the one hand, and such Lender on the other, under the proposed transactions giving rise to or contemplated by the Agreement, such benefits shall be deemed to be in the same proportion as (i) the total value paid or proposed to be paid by you pursuant to the transactions, whether or not consummated, for which such Lender is providing services as provided in the Agreement bears to (ii) the fees paid or proposed to be paid by you or on your behalf to such Lender in connection with the proposed transactions giving rise to or contemplated by the Agreement. The relative fault of the parties shall be determined by reference to, among other things, whether the actions taken or omitted to be taken in connection with the proposed transactions contemplated by the Agreement (including any untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact) relates to information supplied by you on the one hand, or such Lender on the other, the parties' relative intent, knowledge, access to information and opportunity to correct or prevent such

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action, statement or omission or alleged statement or omission, and any other equitable considerations appropriate in the circumstances. No person found liable for a fraudulent misrepresentation shall be entitled to contribution from any person who is not also found liable for such fraudulent misrepresentation; Your indemnity, reimbursement and contribution obligations under this agreement shall be in addition to any rights that the Lenders or any other Indemnified Person may have at common law or otherwise.

        If any action, suit, proceeding or investigation is commenced, as to which an Indemnified Person proposes to demand indemnification, it shall notify you with reasonable promptness; provided, however, that any failure by such Indemnified Person to notify you shall not relieve you from your obligations hereunder (except to the extent that you are materially prejudiced by such failure to promptly notify).

        No Indemnified Person shall be responsible or liable to you or any other person for consequential, special or punitive damages which may be alleged as a result of the Agreement or the financing contemplated thereby. You hereby consent to personal jurisdiction and service and venue in any court in which any claim which is subject to this agreement is brought against either Lender or any other Indemnified Person. This agreement may not be amended or modified except in writing. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK. ANY RIGHT TO TRIAL BY JURY WITH RESPECT TO ANY CLAIM, ACTION, SUIT OR PROCEEDING ARISING OUT OF OR CONTEMPLATED BY THIS AGREEMENT IS HEREBY WAIVED. YOU HEREBY SUBMIT TO THE NON EXCLUSIVE JURISDICTION OF THE FEDERAL AND NEW YORK STATE COURTS LOCATED IN THE CITY OF NEW YORK IN CONNECTION WITH ANY DISPUTE RELATED TO THIS AGREEMENT OR ANY MATTERS CONTEMPLATED HEREBY.

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Bridge Loan and Term Loan Facility Summary Term Sheet ^b

EX-99.(D)(1)

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Exhibit (d)(1)

ElkCorp
14911 Quorum Drive
Suite 600
Dallas, TX 75254

December 29, 2006

CONFIDENTIAL

Heyman Investment Associates Limited Partnership
Building Materials Corporation of America
1361 Alps Road
Wayne, NJ 07470

Ladies and Gentlemen:

        You have requested information from ElkCorp (the "Company"), in connection with your consideration of a possible negotiated transaction between the Company and you (the "Transaction"). As a condition to furnishing such information to you, you agree, as set forth below, to treat confidentially any information (whether prepared by the Company, its Representatives or otherwise, whether in oral, written, electronic or other form, and whether prepared before, on or after the date hereof) that the Company or its Representatives, furnish to you or your Representatives (such information being collectively referred to herein as the "Evaluation Material") and to take or abstain from taking certain other actions set forth herein. The term "Evaluation Material" shall be deemed to include, without limitation, notes, analyses, compilations, summaries, data, studies, interpretations, forecasts, records, memoranda or other documents or information prepared by you or your Representatives which contain, reflect or are based on, in whole or in part, any Evaluation Material. The term "Evaluation Material" shall not be deemed to include information that (i) is already in your possession, provided that such information is not known by you to be subject to another confidentiality agreement with or other obligation of secrecy to the Company or another party, (ii) becomes generally available to the public other than as a result of a disclosure by you or your Representatives, (iii) becomes available to you on a non-confidential basis from a source other than the Company or its Representatives, provided that you do not have reason to believe that such source is bound by a confidentiality agreement with or other obligation of secrecy to the Company or another party, or (iv) you can demonstrate was independently developed by you or on your behalf without violation of any of your obligations hereunder and without reference to any Evaluation Material. Upon the execution of this letter, the Company shall promptly begin facilitating access to diligence materials in response to reasonable requests in connection with your consideration of a Transaction. It is the intent of the Company not to deny you, in connection with your consideration of a Status Quo Offer, access to substantially the same Evaluation Material as was made available to the counterparties to the CGEA Agreement (as defined below), including the guarantor, taking into account, however, that the timing of your review and substance of your requests may differ from those of those counterparties.

        You hereby agree that the Evaluation Material will be used by you or your Representatives solely for the purpose of evaluating a possible acquisition by you of the Company, will not be used in any way directly or indirectly detrimental to the Company, or for any other purpose, and will be kept confidential by you and your Representatives and will not be disclosed by you or any of your Representatives to any other person; provided, however, that any of such information may be disclosed to your Representatives who (i) need to know such information for the sole purpose of evaluating any such possible transaction between the Company and you, (ii) are informed by you of the confidential nature of such information and (iii) agree to keep such information confidential and to be bound by this letter agreement to the same extent as if they were parties hereto. You hereby agree that you will be responsible for any breach of this letter agreement by your Representatives, and that the Company

shall be entitled to directly enforce such agreements (it being understood that such responsibility shall be in addition to and not by way of limitation of any right or remedy the Company may have against your Representatives with respect to such breach). You understand that some Evaluation Material deemed competitively sensitive may, and Evaluation Material related to product pricing shall, if provided, be designated for review solely by your outside advisors or by those of your employees whose responsibilities do not include contacting customers or potential customers or the determination of product pricing, and you agree to, and to cause your Representatives to, abide by such designation.

        In addition, without the prior written consent of the Company, you will not, and will cause your Representatives not to, discuss with or offer to any third party an equity participation in a possible transaction or any other form of joint acquisition by you and such third party, or enter into any agreement relating to the foregoing.

        In the event that you or your Representatives receive a request to disclose all or any part of the information contained in the Evaluation Material under the terms of a valid and effective subpoena or order issued by a court of competent jurisdiction or by a governmental body or are required by applicable law, rule or regulation to disclose such Evaluation Material in connection with your pending offer, you agree (x) in the case of such a request, to (i) to the extent permitted by law, promptly notify the Company in writing of the existence, terms and circumstances surrounding such a request, so that it may seek an appropriate protective order and/or waive your compliance with the provisions of this letter agreement (and, if the Company seeks such an order, to provide such cooperation as the Company shall reasonably request) and (ii) if such protective order or other remedy is not obtained or the Company waives compliance with the provisions of this letter agreement, and if disclosure of such information is required in the opinion of your counsel, who shall be reasonably satisfactory to the Company, disclose only that portion of the Evaluation Material that is legally required to be disclosed in the opinion of such counsel and exercise your reasonable best efforts to obtain an order or other reliable assurance that confidential treatment will be accorded to such of the disclosed information which the Company so designates, and (y) in the case of such a requirement to promptly notify the Company of any such required disclosure and to reasonably cooperate with the Company to agree on the nature of such disclosure; provided, that in the absence of such an agreement, you may disclose such of the Evaluation Material as would be required in the opinion of your counsel, who shall be reasonably satisfactory to the Company, to be disclosed in a proxy statement of the Company for a merger by an acquiror possessing such Evaluation Material.

        During the course of your evaluation, all inquiries and other communications in connection with a possible negotiated Transaction are to be made directly to Thomas Karol, Chief Executive Officer of the Company, or through UBS Investment Bank (primary contact: Lee Lebrun, 212.821.4269), or Wachtell, Lipton, Rosen & Katz ("WLRK") (primary contact: Mark Gordon, 212.403.1343). Until the Standstill Termination Date (as defined below) except with the express written permission of the Company, you will not, and will cause your Representatives not to, initiate or maintain contact with any officer (other than Mr. Karol or Mr. Richard Nowak, the Chief Operating Officer of the Company), employee, agent, or affiliate of the Company or any of its subsidiaries regarding the Company or any of its subsidiaries or their respective operations, assets, prospects or finances, or seek any information from such person, in each case in connection with a possible Transaction. Subject to your compliance with the restrictions of the next paragraph (when applicable to you), you may contact directors of the Company in connection with a possible Transaction.

        You hereby acknowledge that the Evaluation Material is being furnished to you in consideration of your agreement, and you hereby agree, subject to the following paragraph, that from the date hereof until the earlier of: (A) six (6) months from the date of this letter agreement, (B) if the Company advances the Company Proposal Date (as defined below) to a date that is earlier than six months from the date of this letter agreement, the fifth business day prior to such new, earlier Company Proposal Date, or (C) the amendment, waiver or modification of the CGEA Agreement in a manner materially

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adverse to the holders of the Company's common stock, including but not limited to by reducing the Merger Consideration, increasing the conditions to closing or extending the time for performance (such earlier date, the "Standstill Termination Date"), unless specifically invited in writing by the Company, neither you nor any of your Representatives will in any manner, directly or indirectly: (a) effect or seek, offer or propose (whether publicly or otherwise) to effect, or participate in, facilitate or encourage any other person to effect or seek, offer or propose (whether publicly or otherwise) to effect or participate in, (i) any acquisition of any securities (or beneficial ownership thereof), or rights or options to acquire any securities (or beneficial ownership thereof), or any assets, indebtedness or businesses of the Company or any of its subsidiaries, other than acquisitions not in excess of, in the aggregate, 2% of such securities, (ii) any tender offer or exchange offer, merger or other business combination involving the Company, any of the subsidiaries or assets of the Company or the subsidiaries constituting a significant portion of the consolidated assets of the Company and its subsidiaries, (iii) any recapitalization, restructuring, liquidation, dissolution or other extraordinary transaction with respect to the Company or any of its subsidiaries, or (iv) any "solicitation" of "proxies" (as such terms are used in the proxy rules of the Securities and Exchange Commission) or consents to vote any voting securities of the Company, including soliciting consents or taking other action with respect to the calling of a special meeting of the Company's shareholders; (b) form, join or in any way participate in a "group" (as defined under the Exchange Act) with respect to the Company; (c) otherwise act, alone or in concert with others, to seek representation on or to control or influence the management, Board of Directors or policies of the Company or to obtain representation on the Board of Directors of the Company; (d) disclose or direct any person to disclose, any intention, plan or arrangement inconsistent with the foregoing; (e) take any action that could reasonably be expected to result in a request to disclose all or any part of the information contained in the Evaluation Material by a court of competent jurisdiction or by a governmental body; or (f) advise, assist or encourage or direct any person to advise, assist or encourage any other persons in connection with any of the foregoing. You also agree during such period not to request the Company or any of its Representatives, directly or indirectly to amend or waive any provision of this paragraph (including this sentence). The Company has publicly announced that advance notice of any shareholder proposals for business to be conducted at the Company's 2007 annual meeting of stockholders must be given by a proposing shareholder by August 1, 2007. Such deadline is referred to herein as the "Company Proposal Date".

        The preceding paragraph notwithstanding, (1) you will not be deemed to be in breach of the preceding paragraph by virtue of the maintenance, amendment and/or extension by you or your affiliates of the offer (the "Offer") made by and referred to in the Offer to Purchase (the "Offer to Purchase") filed as an exhibit to the Tender Offer Statement on Schedule TO filed by Building Materials Corporation of America with the Securities and Exchange Commission on December 20, 2006, or the announcement, commencement or maintenance by you or your affiliates of a new acquisition offer, whether by way of a tender or exchange offer, merger or otherwise (a "New Offer"); provided that the terms of the Offer or the New Offer (including any extension or amendment thereof) shall in no event (A) provide for a per share consideration that is less than the Offer price in effect on the date of this letter agreement or (B) otherwise contain terms and conditions that in the aggregate are materially less favorable to the Company's shareholders than the terms and conditions set forth in the Offer to Purchase, provided that an extension of the expiration date of the Status Quo Offer shall not be deemed to be an adverse change (an Offer or New Offer made and/or proposed and/or maintained in good faith and meeting the terms of this proviso, a "Status Quo Offer"); and (2) you will not be deemed to be in breach of the preceding paragraph by virtue of the taking of any action otherwise prohibited by such provisions so long as any such action is taken during the time that such Status Quo Offer is pending and open.

        In consideration of the Evaluation Material being furnished to you, you also hereby agree that, for the period of two years from the date hereof, neither you nor any of your Representatives will solicit for employment, or employ, any of the officers or employees of the Company or its affiliates without

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obtaining the prior written consent of the Company; provided, however, that you and your Representatives may engage in general solicitations (and employ pursuant to such solicitations) for employees in the ordinary course of business and consistent with past practice and that you and your Representatives may solicit or employ any officer or employee of the Company or its affiliates six months after such person's employment with the Company or its affiliate, as the case may be, has terminated.

        You understand that neither the Company nor any of its Representatives have made or make any representation or warranty as to the accuracy or completeness of the Evaluation Material and that nothing contained in any discussions between the Company or any of its Representatives and you or any of your Representatives shall be deemed to constitute a representation or warranty. You agree that neither the Company nor its Representatives shall have any liability to you or any of your Representatives resulting from the use or content of the Evaluation Material or from any action taken or any inaction occurring in reliance on the Evaluation Material, except as may be included in any definitive agreement which provides for any transaction between the Company and you.

        At the request of the Company in its sole discretion and for any reason, or on your own initiative if you decide not to proceed with a possible transaction, you will promptly (and in no event later than five business days after the request therefor) deliver to the Company or destroy (including, to the extent practicable, expunging all such Evaluation Material from any computer, word processor or other device containing such information) all Evaluation Material (whether prepared by the Company or its Representatives), including all documents, memoranda, notes and other writings whatsoever prepared by you or your Representatives based on the information in the Evaluation Material, and cause your Representatives to do the same and you shall provide the Company with written confirmation of destruction. Notwithstanding the foregoing, you and your Representatives may retain one copy if and to the extent required in order to satisfy any law, rule or regulation to which you are subject. The return or destruction of the Evaluation Material notwithstanding, you and your Representatives will continue to be bound by your obligations of confidentiality and other obligations hereunder.

        You hereby acknowledge that you are aware, and that you will advise your Representatives who are informed as to the matters which are the subject of this letter agreement, that the United States securities laws prohibit any person who has received from an issuer material, non-public information concerning the matters which are the subject of this letter agreement from purchasing or selling securities of such issuer or from communicating such information to any other person under circumstances in which it is reasonably foreseeable that such person is likely to purchase or sell such securities.

        It is further understood and agreed that no failure or delay by any party in exercising any right, power or privilege under this letter agreement shall operate as a waiver thereof, nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any right, power or privilege hereunder. This letter agreement represents the entire understanding of the parties with respect to the matters referred to in this letter agreement and supersedes all prior understandings, written or oral, between the parties with respect to such matters.

        Each party agrees that unless and until a definitive written agreement between the Company and you with respect to a transaction, if any, has been executed by the Company and you, neither the Company nor you will be under any legal obligation of any kind whatsoever, under any theory of contract, detrimental reliance, fraud or otherwise, with respect to any transaction by virtue of this letter agreement or any written or oral expression with respect to such transactions by any of the Company's or your Representatives. The Company and you each expressly agrees that no negotiations, presentation or exchange of drafts, preliminary agreements with respect to any particular provisions in draft contracts, press releases, disclosures or other statements, oral or written, by mutual consent or otherwise, by either or both parties, execution of any letter of intent, or agreement in principle, or

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similar document, no action by any Representative of either the Company or you, and no resolution or authorization by the Board of Directors or any committee of the Company will evidence an intent to be bound unless and until a mutually agreed upon definitive written agreement is finally completed and duly executed. The Company's and your respective disavowals and agreements in this paragraph will not be waived by any course of dealing prior to the due execution of a mutually agreed upon definitive written agreement. You further acknowledge and agree that (i) the Company shall have no obligation to authorize or to pursue, discuss or negotiate with you or any other party any transaction referred to in the first paragraph of this letter agreement, (ii) you understand that the Company has not, as of the date hereof, authorized any such transaction and (iii) the Company reserves the right, in its sole and absolute discretion, to reject all proposals and to terminate discussions and negotiations with you at any time. The agreements set forth in this letter agreement may be modified or waived only by a separate writing between the Company and you expressly so modifying or waiving such agreements.

        The parties hereto acknowledge that money damages are an inadequate remedy for breach of this letter agreement because of the difficulty of ascertaining the amount of damage that will be suffered by the Company in the event that this agreement is breached. Therefore, you agree that the Company may obtain specific performance of this agreement and injunctive or other equitable relief as a remedy for any such breach, and you further waive any requirement for the securing or posting of any bond in connection with any such remedy. Such remedy shall not be deemed to be the exclusive remedy for your breach of this letter agreement, but shall be in addition to all other remedies available at law or equity to the Company. If any term, provision, covenant or restriction of this letter agreement is held by a court of competent jurisdiction to be invalid, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions of this letter agreement shall remain in full force and effect and shall in no way be affected, impaired or invalidated.

        As used in this letter agreement, (i) the term "person" will be interpreted broadly to include, without limitation, the media (electronic, print or otherwise), the Internet, any governmental representative or authority or any corporation, company, group, partnership, limited liability company, other entity or individual, (ii) the term "Representatives," used with respect to a person, shall include its affiliates and the directors, officers, employees, representatives, agents, attorneys, accountants, financial advisors and other advisors, and banks and other debt financing sources of or to such person or its affiliates, but, without the prior written consent of the Company, shall exclude any potential source of equity capital, (iii) the term "affiliate" when used with respect to a person, shall have the meaning given to it in Rule 12b-2 under the Exchange Act, (iv) the term "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended and (v) the term "change of control" shall mean (a) a sale or transfer of all or substantially all of the assets or stock of the Company or (b) a merger or other business combination to which the Company is a party, except for a merger or other business combination where the Company is the surviving corporation and, after giving effect to such merger, the holders of the Company's outstanding capital stock (on a fully-diluted basis) immediately prior to the merger will own, immediately following the merger, capital stock holding a majority of the voting power of the Company.

        This letter agreement shall be governed by, and construed in accordance with, the laws of the State of New York, without giving effect to the principles of conflicts of laws thereof. You irrevocably submit to (i) the exclusive jurisdiction of New York state courts and any federal court sitting in the City and State of New York for purposes of any suit, action or other proceeding arising out of this letter agreement, or of the transactions contemplated hereby, that is brought by or against you, and (ii) the exclusive venue of such suit, action or proceeding in the City and State of New York.

        Except as provided in the following sentence, this letter agreement and all obligations of the parties hereunder shall terminate two (2) years from the date hereof. Notwithstanding anything in this letter agreement to the contrary, you agree that all of your obligations will survive and continue: (a) with respect to Evaluation Material other than Trade Secret Technology Information, for a period

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of three (3) years from the date hereof, and (b) with respect to Trade Secret Technology Information for so long as such information retains its status as a trade secret. For Purposes of this Agreement: "Trade Secret Technology Information" means Evaluation Material without regard to form which is not commonly known-by or available to the public and which information (i) relates to proprietary inventions, know-how, technology, processes or products of the company, (ii) derives economic value, actual or potential, from not being known to and not being readily ascertainable by proper means by other persons who can obtain economic value from its disclosure or use, (iii) is the subject of efforts that are reasonable under the circumstances to maintain its secrecy, and (iv) is designated as a trade secret by the Company to you by labeling such written information "trade secret" or designating oral information or information conveyed by observation as "trade secret" in writing within thirty (30) days after disclosure of the trade secret to you.

[Signature page follows]

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        If you are in agreement with the foregoing, please so indicate by signing and returning one copy of this letter agreement, which will constitute our agreement with respect to the matters set forth herein.

Very truly yours,
ElkCorp
By:	/s/  THOMAS KAROL
	Name:	Thomas Karol
	Title:	CEO

Confirmed and Agreed to:

HEYMAN INVESTMENT ASSOCIATES LIMITED PARTNERSHIP

By:	/s/  SAMUEL J. HEYMAN
	Name:	Samuel J. Heyman
	Title:	General Partner
BUILDING MATERIALS CORPORATION OF AMERICA
By:	/s/  ROBERT TAFARO
	Name:	Robert Tafaro
	Title:	President & CEO

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QuickLinks

ElkCorp 14911 Quorum Drive Suite 600 Dallas, TX 75254

COVER

January 18, 2007

Securities and Exchange Commission
100 F Street, NE
Washington, DC 20549

Attention:    Office of Financial Management, Fee Unit

Re: BMCA Acquisition Sub Inc.
Tender Offer Statement on Schedule TO under Section 14(d)(1)
of the Securities Exchange Act of 1934

Ladies and Gentlemen:

On behalf of BMCA Acquisition Sub Inc., a Delaware Corporation (the "Purchaser"), and pursuant to (i) Rule 14d-3 promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and (ii) Regulation S-T promulgated by the Securities and Exchange Commission (the "Commission"), we transmit herewith for filing with the Commission via EDGAR, the Schedule TO of the Purchaser, together with all the exhibits thereto (the "Schedule TO") relating to the offer by the Purchaser to purchase for cash all outstanding shares of Common Stock, par value $1.00 per share, of ElkCorp, a Delaware corporation ("ElkCorp").

The aggregate amount of $101,322.48, as calculated pursuant to Rule 0-11(d) promulgated under the Exchange Act, has been transmitted by wire transfer to the Commission's lockbox depository at Mellon Bank as payment of the applicable filing fee. The amount of $4,529.26 was transmitted by the Purchaser by wire transfer to the Commission's lockbox depository at Mellon Bank on January 17, 2007. This amount is in addition to the payment of $94,205.46 made by Building Materials Corporation of America ("BMCA") upon the filing of its Schedule TO on December 20, 2006 and $2,587.76 made by BMCA upon the filing of Amendment No. 1 to its Schedule TO on January 3, 2007. The amount of $282.51 was transferred from the account of BMCA to the account of the Purchaser on January 17, 2007.

By copy of this letter, an executed copy of the Schedule TO transmitted herewith is being hand delivered to the Company and to the New York Stock Exchange.

Should members of the Commission's staff have any questions or comments concerning this matter, please call the undersigned at (212) 728-8000.

Very truly yours,

/s/ Seth J. Zelnick

Seth J. Zelnick, Esq.

Enclosures

cc: ElkCorp
New York Stock Exchange