<SEC-DOCUMENT>0001423221-26-000013.txt : 20260227
<SEC-HEADER>0001423221-26-000013.hdr.sgml : 20260227
<ACCEPTANCE-DATETIME>20260227162113
ACCESSION NUMBER:		0001423221-26-000013
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260226
FILED AS OF DATE:		20260227
DATE AS OF CHANGE:		20260227

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Shah Manish H
		CENTRAL INDEX KEY:			0001849123
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33913
		FILM NUMBER:		26700294

	MAIL ADDRESS:	
		STREET 1:		9618 BOUCHAINE PASS
		CITY:			BRENTWOOD
		STATE:			TN
		ZIP:			37027

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Quanex Building Products CORP
		CENTRAL INDEX KEY:			0001423221
		STANDARD INDUSTRIAL CLASSIFICATION:	ROLLING DRAWING & EXTRUDING OF NONFERROUS METALS [3350]
		ORGANIZATION NAME:           	04 Manufacturing
		EIN:				261561397
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1031

	BUSINESS ADDRESS:	
		STREET 1:		945 BUNKER HILL RD
		STREET 2:		SUITE 900
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77024
		BUSINESS PHONE:		7139614600

	MAIL ADDRESS:	
		STREET 1:		945 BUNKER HILL RD
		STREET 2:		SUITE 900
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77024
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-02-26</periodOfReport>

    <issuer>
        <issuerCik>0001423221</issuerCik>
        <issuerName>Quanex Building Products CORP</issuerName>
        <issuerTradingSymbol>NX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001849123</rptOwnerCik>
            <rptOwnerName>Shah Manish H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>945 BUNKER HILL ROAD</rptOwnerStreet1>
            <rptOwnerStreet2>900</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77024</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2026-02-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1139.09</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>20.85</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1139.09</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6597.723</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Units credited to the participant's account under the Deferred Compensation Plan as a result of deferral of Director Compensation.</footnote>
        <footnote id="F2">Each Phantom Stock Unit is the economic equivalent of one share of common stock.    Distributions under the Deferred Compensation Plan are made in cash beginning on a specified date selected by the participant or upon the participant's death, disability, or termination of service as a director.</footnote>
        <footnote id="F3">Includes 28.246 phantom stock units credited to the participant's account as a result of automatic dividend reinvestment.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Paul B. Cornett, Power of Attorney</signatureName>
        <signatureDate>2026-02-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
