<PAGE>   1


                            AMENDMENT NO. 1 TO THE
                    AMENDED AND RESTATED CREDIT AGREEMENT



                                              Dated as of October  16, 1997


     AMENDMENT NO. 1 TO THE AMENDED AND RESTATED CREDIT AGREEMENT among Penda
Corporation, a Florida corporation (the "Borrower"), the Lenders and Banque
Nationale de Paris, New York Branch, as Agent (the "Agent") for the Lenders.

     PRELIMINARY STATEMENTS:

     (1) The Borrower, the Lenders and the Agent have entered into an Amended
and Restated Credit Agreement dated as of July 14, 1995 (as amended,
supplemented or otherwise modified through the date hereof, the "Credit
Agreement").  Capitalized terms not otherwise defined in this Amendment have
the same meanings as specified in the Credit Agreement.

     (2) The Borrower and the Required Lenders have agreed to amend the Credit
Agreement as hereinafter set forth.

     (3) The Required Lenders are, on the terms and conditions stated below,
willing to grant the request of the Borrower and the Borrower and the Required
Lenders have agreed to amend the Credit Agreement as hereinafter set forth.

     SECTION 1.  Amendments to Credit Agreement.  The Credit Agreement is,
effective as of the date hereof and subject to the satisfaction of the
conditions precedent set forth in Section 4, hereby amended as follows:

     (a)   Section 5.04(b) is amended in full to read as follows:

           "Interest Coverage Ratio.  Maintain, as of the end of each period of
     four Fiscal Quarters, on a Consolidated basis for itself and its 
     Subsidiaries an Interest Coverage Ratio of not less than the amount set
     forth below for such periods set forth below:

<TABLE>
<CAPTION>
     Four Fiscal Quarter                          
     Period Ending On or About                     Ratio
     -------------------------                     -----
     <S>                                           <C>
     September 30, 1995                            1.85
     December 31, 1995                            
       through June 30, 1997                       2.00
     September 30, 1997                            1.75
     December 31, 1997                            
       and thereafter                              2.00"
</TABLE>


            SECTION 2.  Conditions of Effectiveness.  This Amendment shall 
     become effective as of September 30, 1997 when, and only when, the Agent   
     shall have received counterparts of this Amendment executed by the
     Borrower and the Required Lenders or, as to any of the Lenders, advice
     satisfactory to the Agent that such Lender has executed this Amendment and
     the consent attached hereto executed by the Guarantor.  The effectiveness
     of this Amendment is conditioned upon the accuracy of the factual matters
     described herein.  This Amendment is subject to the provisions of Section
     8.01 of the Credit Agreement.

           SECTION 3.  Reference to and Effect on the Loan Documents.  (a)  On 
     and after the effectiveness of this Amendment, each reference in the 
     Credit Agreement to "this Agreement", "hereunder", "hereof" or words of
     like import referring to the Credit Agreement, and each reference in the
     Notes and each of the other Loan Documents to "the Credit Agreement",
     "thereunder", "thereof" or words of like import 




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<PAGE>   2

referring to the Credit Agreement, shall mean and be a reference to the Credit 
Agreement, as amended by this Amendment.

     (b) The Credit Agreement and, the Notes and each of the other Loan
Documents, as specifically amended by this Amendment,  are and shall continue
to be in full force and effect and are hereby in all respects ratified and
confirmed.  Without limiting the generality of the foregoing, the Collateral
Documents and all of the Collateral described therein do and shall continue to
secure the payment of all Obligations of the Loan Parties under the Loan
Documents, in each case as amended by this Amendment.

     (c) The execution, delivery and effectiveness of this Amendment shall not,
except as expressly provided herein, operate as a waiver of any right, power or
remedy of any Lender or the Agent under any of the Loan Documents, nor
constitute a waiver of any provision of any of the Loan Documents.

     SECTION 4.  Costs, Expenses.  The Borrower agrees to pay on demand all
costs and expenses of the Agent in connection with the preparation, execution,
delivery and administration, modification and amendment of this Amendment and
the other instruments and documents to be delivered hereunder (including,
without limitation, the reasonable fees and expenses of counsel for the Agent)
in accordance with the terms of Section 8.04 of the Credit Agreement.

     SECTION 5.  Execution in Counterparts.  This Amendment may be executed in
any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed shall be deemed to be an original
and all of which taken together shall constitute but one and the same
agreement.  Delivery of an executed counterpart of a signature page to this
Amendment by telecopier shall be effective as delivery of a manually executed
counterpart of this Amendment.

     SECTION 6.  Governing Law.  This Amendment shall be governed by, and
construed in accordance with, the laws of the State of New York.

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers thereunto duly authorized, as of the date
first above written.


                                 PENDA CORPORATION                         
                                                                           
                                 By: /s/ Leo E. Waner                      
                                    ----------------------------------
                                 Title:  Vice President - CFO              
                                                                           
                                                                           
                                 BANQUE NATIONAL DE PARIS,                 
                                 as Agent and as Lender                    
                                                                           
                                 By: /s/ Richard Cushing            
                                     ----------------------------------
                                 Title:  Vice President                    
                                                    
                       
                                 By: /s/ Paul Barnes       
                                     ----------------------------------
                                 Title:   Assistant Vice President         
                                                                           
                                                                           
                                 FIRSTAR BANK MILWAUKEE, N.A.              
                                                                           
                                 By: /s/  Randy D. Olver    
                                     ----------------------------------
                                 Title:   Vice President Corporate Banking 



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                                          CONSENT



                                                Dated as of October 16, 1997


     The undersigned, Tri-Glas Corporation, an Alabama corporation, as
Guarantor under the Subsidiaries Guaranty dated July 15, 1995 (the "Guaranty")
in favor of the Agent , for its benefit and the benefit of the Lenders parties
to the Credit Agreement referred to in the foregoing Amendment, hereby consents
to such Amendment and hereby confirms and agrees that (a) notwithstanding the
effectiveness of such Amendment, the Guaranty is, and shall continue to be, in
full force and effect and is hereby ratified and confirmed in all respects,
except that, on and after the effectiveness of such Amendment, each reference
in the Guaranty to the "Credit Agreement", "thereunder", "thereof" or words of
like import shall mean and be a reference to the Credit Agreement, as amended
by such Amendment, and (b) the Collateral Documents to which such Grantor is a
party and all of the Collateral described therein do, and shall continue to,
secure the payment of all of the Secured Obligations (in each case, as defined
therein).


                               TRI-GLAS CORPORATION


                               By:  /s/   Leo  E.  Waner
                                  ---------------------------------------------
                               Title:  Vice President - Chief Financial Officer







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