<SEC-DOCUMENT>0001127602-20-019552.txt : 20200615
<SEC-HEADER>0001127602-20-019552.hdr.sgml : 20200615
<ACCEPTANCE-DATETIME>20200615143129
ACCESSION NUMBER:		0001127602-20-019552
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200615
FILED AS OF DATE:		20200615
DATE AS OF CHANGE:		20200615

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SCRIPTER JAY T
		CENTRAL INDEX KEY:			0001392265

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14649
		FILM NUMBER:		20962900

	MAIL ADDRESS:	
		STREET 1:		1200 WILLOW LAKE BOULEVARD
		STREET 2:		PO BOX 64683
		CITY:			SAINT PAUL
		STATE:			MN
		ZIP:			55164-0683

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
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-06-15</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001069878</issuerCik>
        <issuerName>TREX CO INC</issuerName>
        <issuerTradingSymbol>TREX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001392265</rptOwnerCik>
            <rptOwnerName>SCRIPTER JAY T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O TREX COMPANY, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>160 EXETER DRIVE</rptOwnerStreet2>
            <rptOwnerCity>WINCHESTER</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22603-8605</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>Former VP Operations</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>/s/ William R. Gupp by power of attorney</signatureName>
        <signatureDate>2020-06-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
