-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 NiXWLU14UfUB3fgQKaUQRKrnF3n45qASOeWwtpK04NiTN715hKgykASS62lKnA7+
 7oBqLzYUdUz7PbsylI42ow==

<SEC-DOCUMENT>0001069878-03-000140.txt : 20031014
<SEC-HEADER>0001069878-03-000140.hdr.sgml : 20031013
<ACCEPTANCE-DATETIME>20031014111017
ACCESSION NUMBER:		0001069878-03-000140
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031010
FILED AS OF DATE:		20031014

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FERRARI ANDREW U
		CENTRAL INDEX KEY:			0001105737

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14649
		FILM NUMBER:		03938414

	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>c0001105737d20031013f4f.xml
<DESCRIPTION>PRIMARY DOCUMENT
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lue></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-10-10</value></transactionDate><deemedExecutionDate><value>2003-10-10</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>200</value></transactionShares><transactionPricePerShare><value>32.1</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1254037</value><footnoteId id="F1"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><
value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-10-10</value></transactionDate><deemedExecutionDate><value>2003-10-10</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>200</value></transactionShares><transactionPricePerShare><value>32.16</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1253837</value><footnoteId id="F1"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirec
tOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-10-10</value></transactionDate><deemedExecutionDate><value>2003-10-10</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>200</value></transactionShares><transactionPricePerShare><value>32.17</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1253637</value><footnoteId id="F1"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><dir
ectOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><derivativeTable></derivativeTable><footnotes><footnote id="F1">Does not include Indirect Beneficial Ownership of 850 shares by wife.  Mr. Ferrari disclaims beneficial ownership of these securities, and this report shall not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16 or any other purpose.</footnote></footnotes><ownerSignature><signatureName>Lynn E. MacDonald</signatureName><signatureDate>2003-10-13</signatureDate></ownerSignature></ownershipDocument>

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</DOCUMENT>
</SEC-DOCUMENT>
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