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                                                                    EXHIBIT 10.5

                              ASSUMPTION AGREEMENT

            ASSUMPTION AGREEMENT (this "Agreement"), dated as of April 19, 2002,
is by Associated Materials Incorporated, a Delaware corporation (the "Company"),
and certain of the Company's subsidiaries as set forth on the signature pages
hereto (the "Guarantors").

                               W I T N E S S E T H

            WHEREAS, Simon Acquisition Corp., a Delaware corporation
("Acquisition Corp."), has heretofore executed and delivered to Credit Suisse
First Boston Corporation, UBS Warburg LLC, and CIBC World Markets Corp. (the
"Purchasers") a purchase agreement (the "Purchase Agreement"), dated as of April
18, 2002, providing for the terms pursuant to which the Purchasers will purchase
$165,000,000 aggregate principal amount of 9 3/4% Senior Subordinated Notes due
2012 (the "Notes") of Acquisition Corp.;

            WHEREAS, Acquisition Corp. has been merged with and into the Company
(the "Merger");

            WHEREAS, pursuant to the Purchase Agreement, the Company upon
consummation of the Merger is required to assume all of the obligations of
Acquisition Corp. under the Purchase Agreement and to execute and deliver this
Agreement concurrently with the Merger; and

            WHEREAS, pursuant to the Purchase Agreement, immediately subsequent
to the Merger, each of the Guarantors is required to become a party to the
Purchase Agreement and to guarantee the obligations of the Company with respect
to the Notes thereunder on a senior subordinated basis;

            NOW THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Company and each of the Guarantors mutually covenant and agree for the benefit
of the Purchasers as follows:

            1.    ASSUMPTION. The Company hereby acknowledges that by operation
of law it has become successor to all of the obligations of Acquisition Corp.
and expressly agrees to assume all of the obligations of Acquisition Corp. under
the Purchase Agreement (including the representations and warranties therein,
provided, however, that representations and warranties made by Acquisition Corp.
which explicitly state that such representations and warranties are made by
Acquisition Corp. "to the best knowledge of Acquisition Corp. after
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due inquiry" shall be made on the date hereof by the Company without such
knowledge and due inquiry qualification.

            2.    GUARANTORS. The Guarantors hereby agree to be deemed the
"Guarantors" and "Issuers" for all purposes under the Purchase Agreement and to
perform all obligations and duties of the Guarantors and the Issuers, as the
case may be, under such agreement and agree to take all action required pursuant
to the Purchase Agreement to be named as Guarantor thereunder.

            3.    NEW YORK LAW TO GOVERN. The internal law of the State of New
York, without regard to the choice of law principles thereof, shall govern and
be used to construe this Agreement.

            4.    COUNTERPARTS. The parties may sign any number of copies of
this Agreement. Each signed copy shall be an original, but all of them together
represent the same agreement.

            5.    EFFECT OF HEADINGS. The Section headings herein are for
convenience only and shall not affect the construction hereof.
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      IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered, all as of the date first above written, which is
the date of the Merger.


                                    ASSOCIATED MATERIALS INCORPORATED


                                    By:          /s/ D. Keith LaVanway
                                         -----------------------------------
                                         Name:  D. Keith LaVanway
                                         Title:  Vice President and
                                                 Chief Financial Officer

                                    AMI MANAGEMENT COMPANY


                                    By:          /s/ D. Keith LaVanway
                                         -----------------------------------
                                         Name:  D. Keith LaVanway
                                         Title:  Vice President, Chief
                                                 Financial Officer,
                                                 Secretary and Treasurer