-----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,
 HqTcJp/jiKcQv3ApnDZCNmE3LFGS3DKLJ0r2K+uKF/Mvi6hz53kuMMZhpbqT2OGH
 c4DKhHLFwOseQt/nlY1CLg==

<SEC-DOCUMENT>0001253260-03-000282.txt : 20031216
<SEC-HEADER>0001253260-03-000282.hdr.sgml : 20031216
<ACCEPTANCE-DATETIME>20031216135548
ACCESSION NUMBER:		0001253260-03-000282
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031212
FILED AS OF DATE:		20031216

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:		031056937

	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>c0001105737d20031216f4f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-12-12</value></transactionDate><deemedExecutionDate><value>2003-12-12</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>300</value></transactionShares><transactionPricePerShare><value>39.56</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1195387</value><footnoteId id="F1"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndir
ectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-12-12</value></transactionDate><deemedExecutionDate><value>2003-12-12</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>300</value></transactionShares><transactionPricePerShare><value>39.76</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1195087</value><footnoteId id="F1"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><d
irectOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-12-12</value></transactionDate><deemedExecutionDate><value>2003-12-12</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>300</value></transactionShares><transactionPricePerShare><value>39.95</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>1194787</value><footnoteId id="F1"/></sharesOwnedFollowingTransaction></postTransactionAmounts><owners
hipNature><directOrIndirectOwnership><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>2003-12-16</signatureDate></ownerSignature></ownershipDocument>

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</DOCUMENT>
</SEC-DOCUMENT>
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