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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 fi0Edyvz7HFlPQkFrbxmqw==

<SEC-DOCUMENT>0001253260-04-000021.txt : 20040114
<SEC-HEADER>0001253260-04-000021.hdr.sgml : 20040114
<ACCEPTANCE-DATETIME>20040114171557
ACCESSION NUMBER:		0001253260-04-000021
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040113
FILED AS OF DATE:		20040114

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CAVANNA ANTHONY J
		CENTRAL INDEX KEY:			0001105735

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14649
		FILM NUMBER:		04525609

	BUSINESS ADDRESS:	
		STREET 1:		C/O TREX CO
		STREET 2:		20 SOUTH CAMERON ST
		CITY:			WINCHESTER
		STATE:			VA
		ZIP:			22601

	MAIL ADDRESS:	
		STREET 1:		C/O TREX CO
		STREET 2:		20 SOUTH CAMERON ST
		CITY:			WINCHESTER
		STATE:			VA
		ZIP:			22601

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TREX CO INC
		CENTRAL INDEX KEY:			0001069878
		STANDARD INDUSTRIAL CLASSIFICATION:	LUMBER & WOOD PRODUCTS (NO FURNITURE) [2400]
		IRS NUMBER:				541910453
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		20 CAMERON ST
		CITY:			WINCHESTER
		STATE:			VA
		ZIP:			22801
		BUSINESS PHONE:		5406784070

	MAIL ADDRESS:	
		STREET 1:		20 CAMERON ST
		CITY:			WINCHESTER
		STATE:			VA
		ZIP:			22801
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>c0001105735d20040114f4s1f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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004-01-13</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>100</value></transactionShares><transactionPricePerShare><value>36.66</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1786700</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2004-01-13</value></transactionDate><deemedExecutionDate><value>2004-01-13
</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>100</value></transactionShares><transactionPricePerShare><value>36.69</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1786600</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><derivativeTable></derivativeTable><footnotes></footnotes><ownerSignature><signatureName>Lynn E. MacDonald</signatureName><signatureDate>2004-01-14</signatureDate></owner
Signature></ownershipDocument>

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