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                                                                  EXHIBIT 10.12a

                                 AMENDMENT NO. 1
                                       TO
                                CREDIT AGREEMENT

                  AMENDMENT NO. 1 TO CREDIT AGREEMENT (the "AMENDMENT"), dated
as of September 15, 1998, among American Architectural Products Corporation, a
Delaware corporation, Eagle & Taylor Company, a Delaware corporation, Forte,
Inc., an Ohio corporation, Western Insulated Glass, Co., an Arizona corporation,
Thermetic Glass, Inc., a Delaware corporation, Binnings Building Products, Inc.,
a Delaware corporation, Danvid Window Company, a Delaware corporation, Modern
Window Acquisition Corporation, a Delaware corporation, American Glassmith
Acquisition Corporation, a Delaware corporation, VinylSource, Inc., a Delaware
corporation, Weather-Seal Acquisition Corporation, a Delaware corporation, Eagle
Window & Door Center, Inc., a Delaware corporation, Denver Window Acquisition
Corporation, a Delaware corporation, AAPC One Acquisition Corporation, a
Delaware corporation, and AAPC Two Acquisition Corporation, a Delaware
corporation (the "BORROWERS"), the institutions from time to time parties hereto
(the "LENDERS"), and BankBoston, N.A., in its capacity as contractual
representative for itself and the other Lenders (the "AGENT") under that certain
Credit Agreement dated as of June 9, 1998 by and among the Borrowers, the
Lenders and the Agent (the "CREDIT AGREEMENT"). Defined terms used herein and
not otherwise defined herein shall have the meaning given to them in the Credit
Agreement.

                  WHEREAS, the Borrowers, the Lenders and the Agent have entered
into the Credit Agreement; and

                  WHEREAS, the Borrowers, the Lenders and the Agent have agreed
to amend the Credit Agreement on the terms and conditions set forth herein.

                  NOW, THEREFORE, in consideration of the premises set forth
above, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Borrowers, the Lenders and the
Agent agree as follows:

                  1. AMENDMENT TO THE CREDIT AGREEMENT. Effective as of the date
first above written and subject to the execution of this Amendment by the
parties hereto and the satisfaction of the conditions precedent set forth in
SECTION 2 below, the Credit Agreement shall be and hereby is amended as follows:

                  The definition of "BORROWING BASE" in Section 1.1 is hereby
                  amended to add at the end thereof immediately after the phrase
                  "at the Boardman Aluminum Plant":  ", (10) fifty percent (50%)
                  of the raw materials component and fifty percent (50%) of the
                  finished goods component of the Gross Amount of Eligible
                  Inventory of 


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                  American Glassmith Acquisition Corporation and 0% of any other
                  portion of the Inventory of American Glassmith Acquisition
                  Corporation, (11) fifty percent (50%) of the raw materials
                  component and fifty percent (50%) of the finished goods
                  component of the Gross Amount of Eligible Inventory of
                  Thermetic Glass, Inc. and 0% of any other portion of the
                  Inventory of Thermetic Glass, Inc., and (12) sixty-two percent
                  (62%) of the raw materials component consisting of aluminum,
                  fifty percent (50%) of the raw materials component consisting
                  of glass, and fifty percent (50%) of the finished goods
                  component of the Gross Amount of Eligible Inventory of Western
                  Insulated Glass, Co. and 0% of any other portion of the
                  Inventory of Western Insulated Glass, Co."

                  2. CONDITIONS PRECEDENT. This Amendment shall become effective
as of the date above written, if, and only if, the Agent has received duly
executed originals of this Amendment from the Borrowers, the Lenders and the
Agent.

                  3. REPRESENTATIONS AND WARRANTIES OF THE BORROWERS. The
Borrowers hereby represent and warrant as follows:

                  (a) This Amendment and the Credit Agreement, as amended
hereby, constitute legal, valid and binding obligations of the Borrowers and are
enforceable against the Borrowers in accordance with their terms.

                  (b) Upon the effectiveness of this Amendment, the Borrowers
hereby reaffirm all representations and warranties made in the Credit Agreement,
and to the extent the same are not amended hereby, agree that all such
representations and warranties shall be deemed to have been remade as of the
date of delivery of this Amendment, unless and to the extent that any such
representation and warranty is stated to relate solely to an earlier date, in
which case such representation and warranty shall be true and correct as of such
earlier date.

                  4. REFERENCE TO AND EFFECT ON THE CREDIT AGREEMENT.

                  (a) Upon the effectiveness of Section 1 hereof, on and after
the date hereof, each reference in the Credit Agreement to "this Credit
Agreement," "hereunder," "hereof," "herein" or words of like import shall mean
and be a reference to the Credit Agreement as amended hereby.

                  (b) The Credit Agreement, as amended hereby, and all other
documents, instruments and agreements executed and/or delivered in connection
therewith, shall remain in full force and effect, and are hereby ratified and
confirmed.

                  (c) Except as expressly provided herein, the execution,
delivery and effectiveness of this Amendment shall not operate as a waiver of
any right, power or remedy of the Agent or the Lenders, nor constitute a waiver
of any provision of the Credit Agreement or any other documents, instruments and
agreements executed and/or delivered in connection therewith.


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                  5. GOVERNING LAW. This Amendment shall be governed by and
construed in accordance with the internal laws (as opposed to the conflict of
law provisions) of the State of Illinois.

                  6. HEADINGS. Section headings in this Amendment are included
herein for convenience of reference only and shall not constitute a part of this
Amendment for any other purpose.

                  7. COUNTERPARTS. This Amendment may be executed by one or more
of the parties to the Amendment on any number of separate counterparts and all
of said counterparts taken together shall be deemed to constitute one and the
same instrument.

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                  IN WITNESS WHEREOF, this Amendment has been duly executed and
                  delivered on the date first above written.


AMERICAN ARCHITECTURAL                      BANKBOSTON, N.A.
PRODUCTS CORPORATION                        By: /s/ W. J. Sherald
                                                ------------------------
EAGLE AND TAYLOR COMPANY                        Name: W. J. Sherald
                                                Title: Vice President
FORTE, INC.

WESTERN INSULATED GLASS, CO.

THERMETIC GLASS, INC.

BINNINGS BUILDING PRODUCTS, INC.

DANVID WINDOW COMPANY

MODERN WINDOW ACQUISITION
CORPORATION

AMERICAN GLASSMITH ACQUISITION
CORPORATION

VINYLSOURCE, INC.

WEATHER-SEAL ACQUISITION
CORPORATION

EAGLE WINDOW & DOOR CENTER, INC.

DENVER WINDOW ACQUISITION
CORPORATION

AAPC ONE ACQUISITION CORPORATION

AAPC TWO ACQUISITION CORPORATION

By:  /s/ Richard L. Kovach
     ---------------------------------------
     (on behalf of the parties named above)
     Name: Richard L. Kovach
     Title: Chief Financial Officer