EXHIBIT 3.18
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                           CERTIFICATE OF AMENDMENT OF
                            ARTICLES OF INCORPORATION
                           OF VARIFORM PLASTICS, INC.
                           --------------------------

         Pursuant to "The General and Business Corporation Law of Missouri", the
undersigned corporation hereby certifies the following:

         1.       The name of the corporation is "Variform Plastics, Inc.".

         2.       The amendment set forth in paragraph 3 below was adopted in
the manner prescribed by "The General and Business Corporation Law of Missouri"
by written consent of the shareholders of the corporation dated June 19, 1981.

         3.       The amendment adopted by the shareholders is as follows,
to-wit:

                  The Articles of Incorporation of Variform Plastics, Inc. be
and the same are hereby amended by striking therefrom Article III and Article VI
as presently constituted and inserting in lieu thereof the following provisions:

                                   ARTICLE III

         The aggregate number of shares which the corporation shall have
authority to issue shall be 67,000 shares, of which 64,000 shares shall be
preferred stock having a par value of $1.00 per share and 3,000 shares shall be
common stock having a par value of $10.00 per share. The preferred stock may be
issued from time to time in one or more series, each of such series to have such
voting powers (full or limited or without voting powers) designation,
preferences and relative, participating, optional or other special rights and
qualifications, limitations or restrictions thereof as stated and expressed
herein, or in a resolution or resolutions providing for the issue of such series
adopted by the Board of Directors as hereinafter provided. Authority is hereby
granted to the Board of Directors, subject to the provisions of this Article
III, to create one or more series of preferred stock and, with respect to each
series, to fix or alter as permitted by law, by resolution or resolutions
providing for the issue of such series:

         (a)      the number of shares to constitute such series and the
      distinctive designation thereof;

         (b)      the dividend rate on the shares of such series, the dividend
      payment dates, the periods in respect of which dividends are payable
      ("dividend periods") whether such dividends shall be cumulative, and if
      cumulative, the date or dates from which dividends shall accumulate;

         (c)      whether or not the shares of such series shall be redeemable,
      and, if redeemable, on what terms, including the redemption prices which



      the shares of such series shall be entitled to receive upon the redemption
      thereof;

         (d)      whether or not the shares of such series shall be subject to
      the operation of retirement or sinking funds to be applied to the purchase
      or redemption of such shares for retirement and, if such retirement or
      sinking fund or funds be established, the annual amount thereof and the
      terms and provisions relative to the operation thereof;

         (e)      whether or not the shares of such series shall be convertible
      into, or exchangeable for, shares of any other class or classes or of any
      other series of the same or any other class or classes of stock of the
      Corporation and the conversion price or prices or rate or rates, or the
      rate or rates at which such exchange may be made, with such adjustments,
      if any, as shall be stated and expressed or provided in such resolution or
      resolutions;

         (f)      the voting power, if any, of the shares of such series;

         (g)      the amounts, if any, payable on the shares of such series in
      the events of dissolution or liquidation; and

         (h)      such other terms, conditions, special rights and protective
      provisions as the Board of Directors may be deem advisable.

No dividend shall be declared and set apart for payment on any series of
preferred stock in respect of any dividend period unless there shall likewise be
or have been paid, or declared and set apart for payment, on all shares of
preferred stock of each other series entitled to cumulative dividends at the
time outstanding which rank equally as to dividends with the series in question,
dividends ratably in accordance with the sums which would be payable on the said
shares through the end of the last preceding dividend period if all dividends
were declared and paid in full.

                                   ARTICLE VI

         The number of directors to constitute the board of directors of the
corporation shall be three (3) to be elected by the holders of its common stock
of the corporation, except in the event that the corporation is in default in
the performance of any of its obligations under its Second Amended Plan of
Reorganization, the holders of its common stock shall have the right to elect
two of the three directors, and in such event the holders of its preferred stock
shall have the right to elect one of the three directors.

         4.       At the time the foregoing amendment was adopted, there were
Two Thousand Seven Hundred (2,700) shares of the Common Stock of the Corporation
outstanding, all of which were entitled to vote on the foregoing amendment.


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         5.       Two Thousand Seven Hundred (2,700) shares of Common Stock were
voted in favor of the foregoing amendment and no (-0-) shares were voted against
said amendment.

                  IN WITNESS WHEREOF, the undersigned President and Secretary of
Variform Plastics, Inc. have executed this instrument and affixed hereto the
corporate seal of said corporation on this 19th day of JUNE 1981 .


                                    VARIFORM PLASTICS, INC.


                                    By  /s/ Ralph L. Ayers
                                        ---------------------------------------
                                                     President


                                        /s/ Susan L. Ayers
                                        ---------------------------------------
                                                     Secretary



STATE OF MISSOURI       )
                        )
COUNTY OF JACKSON       )  ss.

                  I, MELINDA A LAGER, a Notary Public, do hereby certify that on
this 19th day of June, 1981, personally appeared before me Ralph L. Ayers who
being by me first duly sworn, declared that he is the President of Variform
Plastics, Inc., that he signed the foregoing document acting in said capacity
for the corporation and that the statements therein contained are true.



                                        /s/ Melinda A. Lager
                                        ---------------------------------------
                                                     Notary Public

My Commission Expires:


       11-12-82
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                                                FILED AND CERTIFICATE
                                                ISSUED
                                                JUN 25 1981


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