Exhibit 5.1








                                                                __________, 2002

Gibraltar Steel Corporation
3556 Lake Shore Road
P.O. Box 2028
Buffalo, New York 14219-0228

                                        Re:   Gibraltar Steel Corporation
                                              Registration Statement on Form S-3

Gentlemen:

                  We have acted as counsel for Gibraltar Steel Corporation, a
Delaware corporation (the "Company"), in connection with the preparation and
filing of a registration statement of the Corporation on Form S-3 (the
"Registration Statement") under the Securities Act of 1933, as amended, relating
to the proposed offering of up to 3,450,000 (the "Shares") of its common stock,
par value $.01 per share (including up to 450,000 which may be sold by the
underwriters named therein pursuant to an over-allotment option), up to
2,950,000 of which Shares are being sold by the Company (the "Primary Shares")
and 500,000 of which Shares are being sold by the selling stockholders (the
"Secondary Shares"). The Shares will be issued and sold pursuant to an
underwriting agreement (the "Underwriting Agreement") to be entered into among
Salomon Smith Barney Inc., as representative of the several underwriters named
therein, the Company and the selling stockholders named therein.

                  In so acting, we have examined copies (certified or otherwise
identified to our satisfaction) of the form of Underwriting Agreement to be
filed as an exhibit to the Registration Statement, the form of resolutions (the
"Resolutions") proposed to be adopted by the pricing committee (the "Pricing
Committee") of the Board of Directors of the Company authorizing the issuance
and sale of the Primary Shares pursuant to the Underwriting Agreement and such
corporate records, agreements, documents and other instruments, and such
certificates or comparable documents of public officials and of officers and
representatives of the Company, and have made such inquiries of such officers
and representatives, as we have deemed relevant and necessary as a basis for the
opinions hereinafter set forth.

                  In such examination, we have assumed the genuineness of all
signatures, the legal capacity of all natural persons, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as certified, conformed or photostatic copies and
the



authenticity of the originals of such latter documents. As to all questions of
fact material to these opinions that have not been independently established, we
have relied upon certificates or comparable documents of officers and
representatives of the Company. We have also assumed for purposes hereof that
(i) the Underwriting Agreement will be executed and delivered in substantially
the form thereof to be filed as an exhibit to the Registration Agreement and
(ii) the Pricing Committee will adopt the Resolutions authorizing the issuance
and sale of the Primary Shares pursuant to the Underwriting Agreement in
substantially the form reviewed by us.

                  Based on the foregoing, and subject to the qualifications
stated herein, we are of the opinion that:

                  1. The Company is a corporation validly existing and in good
standing under the laws of the State of Delaware.

                  2. The Primary Shares, when issued and sold in the manner
described in the Registration Statement and in accordance with the Resolutions
and the terms of the Underwriting Agreement, will be duly authorized, validly
issued, fully paid and non-assessable.

                  3. The Secondary Shares have been duly authorized, validly
issued and are fully paid and non-assessable.

                  We hereby consent to the use of this letter as an exhibit to
the Registration Statement and to any and all references to our firm in the
Prospectus which is a part of the Registration Statement.

                                                 Very truly yours,

                                   /s/ LIPPES, SILVERSTEIN, MATHIAS & WEXLER LLP