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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Wz4R0gMLDC3c9uRS09sAEMtLVa9UHvIusqrVa95ZQL34HJTkq0IDXkm7Cc2oVMEf
 UxNO8PmnGZLm5xuZzxhpcA==

<SEC-DOCUMENT>0001253260-03-000005.txt : 20030716
<SEC-HEADER>0001253260-03-000005.hdr.sgml : 20030716
<ACCEPTANCE-DATETIME>20030716141639
ACCESSION NUMBER:		0001253260-03-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030715
FILED AS OF DATE:		20030716

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:		03788975

	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>c0001105735d20030716f4f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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</transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1922692</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity><nonDerivativeSecurity><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-07-15</value></transactionDate><deemedExecutionDate><value>2003-07-15</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>100</value></transactionShares><transactionValue><value>38.59</value></transactionValue><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCo
de></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1922592</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity><nonDerivativeSecurity><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-07-15</value></transactionDate><deemedExecutionDate><value>2003-07-15</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>100</value></transactionShares><transactionValue><value>38.84</value></transactionValue><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTr
ansactionAmounts><sharesOwnedFollowingTransaction><value>1922492</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity><footnotes></footnotes><ownerSignature><signatureName>Lynn E. MacDonald</signatureName><signatureDate>2003-07-16</signatureDate></ownerSignature></ownershipDocument>

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</SEC-DOCUMENT>
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