**EXHIBIT2.12**      Fifth Supplemental Indenture (this “Fifth Supplemental Indenture”), dated as ofFebruary 27th, 2006, among Ainsworth Lumber Co. Ltd., a corporation incorporated underthe laws of the Province of British Columbia (the “Company”), and Ainsworth Corp., AinsworthEngineered Corp. (“Ainsworth Engineered”), Ainsworth Engineered (USA), LLC (“Ainsworth USA”),Ainsworth Engineered Canada Limited Partnership (“Ainsworth Partnership”), each a subsidiary of theCompany (together, the “Guarantors”), and The Bank of New York, as trustee under the Indenturereferred to below (the “Trustee”).WITNESSETH     WHEREAS, the Company has heretofore executed and delivered to the Trustee an indenture, datedas of March 3, 2004, providing for the issuance of an unlimited aggregate principal amount of6.750% Senior Notes due March 15, 2014 (the “Notes”), as supplemented by the First SupplementalIndenture, dated as of May 19, 2004, among the Company, Ainsworth Engineered and the Trustee, theSecond Supplemental Indenture, dated as of September 22, 2004, among the Company, AinsworthEngineered, Ainsworth USA and the Trustee, the Third Supplemental Indenture, dated as of January10, 2005, among the Company, Ainsworth Engineered, Ainsworth USA, Ainsworth Partnership and theTrustee and the Fourth Supplemental Indenture, dated as of January 31, 2006, among the Company, theGuarantors and the Trustee (as supplemented, the “Indenture”);     WHEREAS, pursuant to a Consent Solicitation Statement, dated February 2, 2006, as amended onFebruary 10, 2006 (the “Solicitation Statement”), the Company solicited the consents (the“Consents”) of Holders of the Notes to amend the Indenture (the “Proposed Amendments”);     WHEREAS, the Holders of a majority of the aggregate principal amount of the outstanding Noteshave validly delivered and not validly withdrawn their Consents to the Proposed Amendments (the“Requisite Consents”) and the Company has accepted those Consents pursuant to the SolicitationStatement;     WHEREAS, all things necessary to make this Fifth Supplemental Indenture a valid supplement tothe Indenture have been done; and     WHEREAS, pursuant to Section 9.02 of the Indenture, the Trustee is authorized to execute anddeliver this Supplemental Indenture.     NOW THEREFORE, the parties agree as follows:     SECTION 1. Certain Definitions. Unless otherwise stated, all capitalized terms used but notdefined herein shall have the meanings ascribed thereto in the Indenture.     SECTION 2. Amendments to the Indenture. The following amendments to the Indenture are herebymade:     (a) Deleting the word “and” from the end of subsection 12 of the definition of Permitted Liensin Section 1.01 of the Indenture;
 

 
     (b) Deleting the period from the end of subsection 13 of the definition of Permitted Liens inSection 1.01 of the Indenture and replacing it with a semicolon followed by the word “and”;     (c) Adding the following new subsection 14 to the definition of Permitted Liens in Section1.01 of the Indenture:(14) Liens securing Purchase Money Indebtedness; *provided, however,*that (a) suchPurchase Money Indebtedness shall not exceed the purchase price or other cost ofsuch property or equipment and shall not be secured by any property or equipment ofthe Company or any Restricted Subsidiary of the Company other than the property andequipment so acquired and (b) the Lien securing such Purchase Money Indebtednessshall be created within 90 days of such acquisition.     ; and     (d) Adding the following definition to Section 1.01 of the Indenture:“Purchase Money Indebtedness” means Indebtedness of the Company and its RestrictedSubsidiaries for the purpose of financing all or any part of the purchase price, orthe installation, construction or improvement, of property (including CapitalStock) or equipment.     SECTION 3. Effectiveness. This Fifth Supplemental Indenture shall become effective uponexecution and delivery hereof.     SECTION 4. Governing Law. This Fifth Supplemental Indenture shall be governed by andconstrued in accordance with the laws of the State of New York, as applied to contracts made andperformed within the State of New York.     SECTION 5. Counterparts. This Fifth Supplemental Indenture may be signed in any number ofcounterparts, each of which shall be an original, with the same effect as if the signatures theretoand hereto were upon the same instrument.     SECTION 6. Severability. In case any provision in this Fifth Supplemental Indenture shall beinvalid, illegal or unenforceable, the validity, legality and enforceability of the remainingprovisions shall not in any way be affected or impaired thereby.     SECTION 7. Ratification. Except as expressly amended hereby, each provision of the Indentureshall remain in full force and effect and, as amended hereby, the Indenture is in all respectsagreed to, ratified and confirmed by each of the Issuer, the Guarantors and the Trustee.     SECTION 8. Trustee Makes No Representation. The Trustee makes no representation as to thevalidity or sufficiency of this Fifth Supplemental Indenture. The statements and recitals hereinare deemed to be those of the Issuer and the Guarantors and not of the Trustee.
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     SECTION 9. Successors and Assigns. All covenants and agreements in this Fifth SupplementalIndenture by the Issuer, the Guarantors, the Trustee and the Holders shall bind their respectivesuccessors and assigns, whether so expressed or not.     SECTION 10. Effect of Headings. The Section headings herein are for convenience only andshall not effect the construction hereof.
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     IN WITNESS WHEREOF, the parties hereto have caused this Fifth Supplemental Indenture to beduly executed, all as of the date first above written.         Ainsworth Lumber Co. Ltd.         By: /s/  Catherine E. Ainsworth          Name: Catherine E. Ainsworth    Title: Chief Operating Officer         By: /s/  D. Michael Ainsworth          Name: D. Michael Ainsworth    Title: Executive Vice-President         Ainsworth Engineered Corp.         By: /s/  Catherine E. Ainsworth          Name: Catherine E. Ainsworth    Title: Secretary         Ainsworth Engineered (USA), LLC         By: /s/  Catherine E. Ainsworth          Name: Catherine E. Ainsworth    Title: Secretary         Ainsworth Engineered Canada Limited Partnership         By: /s/  Robert Allen          Ainsworth Lumber Co. Ltd., its General Partner    Name: Robert Allen    Title: Chief Financial Officer         Ainsworth Corp.         By: /s/  Catherine E. Ainsworth          Name: Catherine E. Ainsworth    Title: Chief Executive Officer         The Bank of New York, as Trustee         By: /s/  Stanislav Pertsev          Authorized Signatory
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