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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 IAoguLZSXlOZyIwjjSzHqfjZ94Nj3R65Htvi0WJaqqE5MYYeM2FqBGJ+joKPkxi/
 g0rNxZR8nFWau3634z2Uow==

<SEC-DOCUMENT>0000032017-06-000100.txt : 20061219
<SEC-HEADER>0000032017-06-000100.hdr.sgml : 20061219
<ACCEPTANCE-DATETIME>20061219154229
ACCESSION NUMBER:		0000032017-06-000100
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20061215
FILED AS OF DATE:		20061219
DATE AS OF CHANGE:		20061219

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ELKCORP
		CENTRAL INDEX KEY:			0000032017
		STANDARD INDUSTRIAL CLASSIFICATION:	ASPHALT PAVING & ROOFING MATERIALS [2950]
		IRS NUMBER:				751217920
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		14911 QUORUM DRIVE
		STREET 2:		SUITE 600
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75254-1491
		BUSINESS PHONE:		9728510500

	MAIL ADDRESS:	
		STREET 1:		14911 QUORUM DRIVE
		STREET 2:		SUITE 600
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75254-1491

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ELCOR CORP
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ELCOR CHEMICAL CORP
		DATE OF NAME CHANGE:	19761119

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			NOWAK RICHARD A
		CENTRAL INDEX KEY:			0001163282

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-05341
		FILM NUMBER:		061286491

	BUSINESS ADDRESS:	
		STREET 1:		14643 DALLAS PKWY
		STREET 2:		STE 1000
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75254-8890
		BUSINESS PHONE:		972 851 0500

	MAIL ADDRESS:	
		STREET 1:		14643 DALLAS PAKWAY
		STREET 2:		STE 1000
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75254-8890
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-12-15</periodOfReport>

    <issuer>
        <issuerCik>0000032017</issuerCik>
        <issuerName>ELKCORP</issuerName>
        <issuerTradingSymbol>ELK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001163282</rptOwnerCik>
            <rptOwnerName>NOWAK RICHARD A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>14911 QUORUM DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 600</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75254-1491</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and COO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $1 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2006-12-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>31</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.38</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>65466</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $1 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2006-12-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>156</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.12</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>65310</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares delivered to pay tax liability on vested stock.</footnote>
        <footnote id="F2">The stock vested 20% on October 29, 2006 at this price.</footnote>
        <footnote id="F3">The stock vested 20% on October 31, 2006 at this price.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Richard A. Nowak</signatureName>
        <signatureDate>2006-12-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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