<SEC-DOCUMENT>0001127602-17-024859.txt : 20170803
<SEC-HEADER>0001127602-17-024859.hdr.sgml : 20170803
<ACCEPTANCE-DATETIME>20170803155153
ACCESSION NUMBER:		0001127602-17-024859
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170802
FILED AS OF DATE:		20170803
DATE AS OF CHANGE:		20170803

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Gupp William R.
		CENTRAL INDEX KEY:			0001428106

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14649
		FILM NUMBER:		171004726

	MAIL ADDRESS:	
		STREET 1:		C/O TREX COMPANY
		STREET 2:		160 EXETER DRIVE
		CITY:			WINCHESTER
		STATE:			VA
		ZIP:			22603

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:		160 EXETER DRIVE
		CITY:			WINCHESTER
		STATE:			VA
		ZIP:			22603-8605
		BUSINESS PHONE:		5405426300

	MAIL ADDRESS:	
		STREET 1:		160 EXETER DRIVE
		CITY:			WINCHESTER
		STATE:			VA
		ZIP:			22603-8605
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>PRIMARY DOCUMENT
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            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22603-8605</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>/s/ William R. Gupp</signatureName>
        <signatureDate>2017-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
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</SEC-DOCUMENT>
