<PAGE>
                                                                   EXHIBIT 10(a)


                                September 1, 2001




Martin Industries, Inc.
Attention: Mr. Alex R. Godwin
Assistant Vice President of Finance
P.O. Box 128
Florence, Alabama 35631


Re:      Line of Credit (Account #120435-524769); Term Loan (Account
         #120435-087445 and #120435-087452); Loan Agreement dated January 7,
         1993, as amended April 5, 1994, February 17, 1995, March 15, 1995,
         March 28, 1996, August 28, 1997, January 1, 2000, December 29, 2000,
         January 31, 2001, March 15, 2001, May 15, 2001 and June 15, 2001
         (collectively "Loan Agreement") by and among Martin Industries, Inc.
         ("Martin Industries") and AmSouth Bank ("the Bank"). In this letter
         capitalized terms shall be given the meanings indicated in the Loan
         Agreement and/or in this letter.

Dear Mr. Godwin:

I am writing this letter to you concerning the indebtednesses ("Indebtednesses")
referenced above of Martin Industries to the Bank and your recent request that
the Loan Agreement be amended to effect an increase the amount of funds
available under the Line of Credit and a waiver by the Bank of compliance by
Martin Industries with certain of the covenants contained therein. In response
to that request, the Bank hereby amends the Loan Agreement as follows:

A.       The term "Borrowing Base" is hereby amended in its entirety to read as
follows:

         "BORROWING BASE" shall mean, from September 1, 2001 through October 31,
2001, the sum of (a) 90% of the Net Outstanding Amount of Eligible Accounts
other than Eligible Dating Accounts, plus (b) 80% of the Net Outstanding Amount
of Eligible Dating Accounts, plus (c) 35% of the collateral value of Eligible
Finished Goods Inventory, plus (d) 28% of the collateral value of Eligible Raw
Material Inventory. From November 1, 2001 until the Line of Credit Termination
Date, "Borrowing Base" shall mean the sum of (a) 80% of the Net Outstanding
Amount of Eligible Accounts, plus (b) 80% of the Net Outstanding Amount of
Eligible Dating Accounts, plus (c) 35% of the collateral value of Eligible
Finished Goods Inventory, plus (d) 28% of the collateral value of Eligible Raw
Material Inventory.

B.       The following definitions are hereby added in order to Section 1.02 of
the Loan Agreement:

         "ELIGIBLE ACCOUNT shall mean and include only Accounts, exclusive of
Eligible Dating Accounts, that are not more than 30 days past due, in each case
according to the terms shown on the invoice (or the date of the invoice where
terms are not specifically stated) and represent sums


                                       1
<PAGE>

payable for services rendered or goods sold or leased by the Borrower in the
ordinary course of business, as the Lender shall deem eligible based on such
credit and collateral considerations as the Lender shall deem appropriate.
Without limiting the generality of the foregoing, there shall be excluded any
Account from Eligible Accounts if and to the extent:

                           (i)      the subject goods have been shipped or
                           delivered to a Purchaser on a bill-and-hold,
                           guaranteed sale, consignment, approval or sale-or-
                           return basis or subject to any other repurchase or
                           return agreement; or

                           (ii)     any material part of the subject goods has
                           been returned, rejected, lost or damaged; or

                           (iii)    the Purchaser is located outside the United
                           States; or

                           (iv)     the Purchaser is also the Borrower's
                           Affiliate, or

                           (v)      the Purchaser is also the Borrower's
                           supplier or creditor, to the extent of amounts due
                           from the Borrower to such supplier or creditor; or

                           (vi)     the Account is not evidenced by an invoice
                           in form acceptable to the Lender; or

                           (vii)    more than 50% in amount of the other
                           Accounts of the Purchaser are more than 60 days past
                           due; or

                           (viii)   the Account arises out of transactions with
                           an employee, officer, agent, director, stockholder or
                           Affiliate of the Borrower; or

                           (ix)     the general creditworthiness and financial
                           condition of the Purchaser are not acceptable to the
                           Lender; or

                           (x)      the Lender believes, in its sole judgment,
                           that the collection of such Account is insecure or
                           that such Account may not be paid by reason of the
                           Purchaser's financial ability to repay; or

                           (xi)     the Borrower has disclosed to the Lender
                           that it does not make any of the representations or
                           warranties set forth in the Security Agreement with
                           respect to such Account or if any of such
                           representations or warranties are not true and
                           correct with respect to such Account; or

                           (xii)    the Account derives from, or is owed to,
                           any foreign Affiliate or subsidiary of the Borrower."


                                       2
<PAGE>

         "ELIGIBLE DATING ACCOUNT shall mean and include only Accounts that
arise under a receivables dating program or "early booking" program of the
Borrower which are not more than 30 days past due, in each case according to the
terms shown on the invoice (or the date of the invoice where terms are not
specifically stated) and represent sums payable for services rendered or goods
sold by the Borrower in the ordinary course of business, as the Lender, in its
sole credit judgment, shall deem eligible based on such credit and collateral
considerations as the Lender shall deem appropriate, including, without
limitation, those factors set forth under the definition of 'Eligible Account.'"

         "NET OUTSTANDING AMOUNT OF ELIGIBLE DATING ACCOUNTS shall mean the net
outstanding amount of all then Eligible Dating Accounts after eliminating from
the aggregate face amount thereof all payments, adjustments, discounts, credits
and allowances applicable thereto and all amounts due thereon considered by the
Lender difficult to collect or uncollectible by reason of return, rejection,
repossession or loss of, or damage to, the merchandise covered thereby,
disputes, financial difficulty of the Purchaser or otherwise, all as determined
by the Lender in its sole discretion."

C.       The form of Borrowing Based Certification to the Bank, as included as
         Exhibit B to the Fifth Amendment to Loan Agreement and Other Loan
         Documents dated as of June 15, 2001, is hereby amended and replaced by
         the form of Borrowing Based Certification included as Exhibit A-1
         hereto for the period from September 1, 2001 through October 31, 2001.
         From November 1, 2001 until the Line of Credit Termination Date, the
         form of Borrowing Base Certification to the Bank shall be the form
         included as Exhibit A-2 hereto.

In addition to the foregoing, the Bank waives with respect to the period ended
August 4, 2001, any default or Event of Default arising out of the Borrower's
failure to comply with Section 8.20 of the Loan Agreement.

In all other respects, the Loan Agreement shall remain in full force and effect
in accordance with its terms.

To evidence the acceptance of the foregoing amendment and waiver on the terms
and conditions set forth herein, please sign and return to me the enclosed copy
of this letter agreement. By so signing the enclosed copy of this letter
agreement, Martin Industries acknowledges and agrees to the following terms and
conditions of such amendment and waiver:

1.       This letter agreement shall not be deemed to be an accord and
         satisfaction of the Indebtednesses or any other obligation owed to the
         Bank.

2.       All collateral that now secures all or any of the Indebtednesses shall
         continue to secure same. Nothing in this letter agreement diminishes
         any security interest or lien that the Bank has in any assets securing
         the Indebtednesses. All of the collateral, rights, security, and
         guarantees that the Bank now has to secure any of the Indebtednesses
         due from Martin Industries shall remain in full force and effect and
         are hereby ratified and confirmed.

3.       Except as provided by the waiver contained in this letter agreement
         with respect to Section 8.20 of the Loan Agreement (the "Waiver"), the
         Bank reserves all of its rights and remedies


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<PAGE>

         under the Loan Agreement, the Security Documents, any other Loan
         Documents, and/or applicable law, in respect of any Event(s) of
         Default. The current non-exercise by the Bank of any rights and
         remedies which it may have shall not constitute a release or waiver of
         any of its rights and/or remedies or a release or waiver of any
         Event(s) of Default under the Loan Agreement, the Security Documents,
         or any other Loan Documents, except for the Waiver provided in this
         letter agreement. The Bank specifically reserves the right to invoke
         any and all rights and remedies at any time in its sole discretion.

4.       Martin Industries hereby releases, satisfies, cancels, waives, acquits,
         and forever discharges the Bank, its directors, officers, employees,
         agents, attorneys, successors and assigns, of and from any and all
         claims, demands, actions, or causes of action of any kind or character,
         arising at any time in the past, up to and including the date of this
         letter agreement, which relate or pertain in any way to the
         Indebtednesses and/or collection of them.

5.       The Indebtednesses are owed by Martin Industries to the Bank for the
         amounts (exclusive of outstanding letters of credit, ACH exposures and
         the Bank's attorneys fees) herein stated and there are no defenses,
         setoffs, or counterclaims with respect to any of them:

<TABLE>
<CAPTION>
                                                           Payoff as of
 General Description          Obligation No.                 09/13/01
---------------------       ------------------         --------------------
<S>                         <C>                        <C>

Term Loan #1                     #087452                   $2,079,355.03
Line of Credit                   #524769                   $8,015,877.15
</TABLE>

6.       Martin Industries agrees to pay the Indebtednesses strictly and
         promptly in accordance with the terms of the applicable promissory
         notes or other debt instruments, as specifically modified by the Loan
         Agreement and this letter agreement.

7.       Martin Industries shall pay to the Bank a fee in the amount of Five
         Thousand dollars ($5,000) upon the execution of this letter agreement.

8.       Martin Industries agrees to pay to the Bank's counsel, Wilmer, Lee &
         Rowe, P.A., on or before September 30, 2001, all of its attorney's fees
         incurred in connection with this amendment and/or the collection of the
         Indebtednesses.

                                                     Very truly yours,

                                                     /s/ Darlene Chandler
                                                     Darlene Chandler
                                                     Vice President

cc:      Mr. John L. Duncan
         Denson N. Franklin III, Esq.
         S. Dagnal Rowe, Esq.


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<PAGE>


ACCEPTED AND AGREED TO BY:

   MARTIN INDUSTRIES, INC.


By:               /s/ Alex R. Godwin
    -------------------------------------------------
                    Alex R. Godwin
        Its Assistant Vice President of Finance


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<PAGE>


                                                                     EXHIBIT A-1

                             MARTIN INDUSTRIES, INC.

                  BORROWING BASE CERTIFICATION TO AMSOUTH BANK
            (For use from September 1, 2001 through October 31, 2001)
                          Status as of _______________

         Pursuant to Section 3.08 of the Loan Agreement originally dated as of
January 7, 1993, as amended, by and between the respective predecessors in
interest of Martin Industries, Inc. (the "Borrower") and AmSouth Bank (the
"Lender"), as of ___________, the Borrower hereby certifies to the Lender as
follows:

<TABLE>
<S>     <C>                                                             <C>                     <C>

1.       Net Outstanding Amount of Eligible Accounts
                                                                        $
                                                                         -------------

2.       90% of Net Outstanding Amount of Eligible Accounts
                                                                                                $
                                                                                                 -------------

3.       Net Outstanding Amount of Eligible Dating Accounts
                                                                        $
                                                                         -------------

4.       80% of Net Outstanding Amount of Eligible Dating Accounts
                                                                                                $
                                                                                                 -------------

5.       Collateral value of Eligible Finished Goods Inventory
                                                                        $
                                                                         -------------

6.       35% of collateral value of Eligible Finished Goods Inventory
                                                                                                $
                                                                                                 -------------

7.       Collateral value of Eligible Raw Material Inventory
                                                                        $
                                                                         -------------

8.       28% of collateral value of Eligible Raw Material Inventory
                                                                                                $
                                                                                                 -------------



9.       TOTAL BORROWING BASE                                                                   $
                                                                                                 -------------


10.      Maximum Line of Credit Amount                                                          $
                                                                                                 -------------



11.      Amount Outstanding Under Line of Credit                                                $
                                                                                                 -------------


12.      AMOUNT AVAILABLE UNDER LINE OF CREDIT                                                  $
                                                                                                 -------------
</TABLE>


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<PAGE>

Borrower:

MARTIN INDUSTRIES, INC.

By:
   ------------------------
Its:
    -----------------------


                                       7
<PAGE>


                                                                     EXHIBIT A-2

                             MARTIN INDUSTRIES, INC.

                  BORROWING BASE CERTIFICATION TO AMSOUTH BANK
    (For use from November 1, 2001 until the Line of Credit Termination Date)
                          Status as of _______________

         Pursuant to Section 3.08 of the Loan Agreement originally dated as of
January 7, 1993, as amended, by and between the respective predecessors in
interest of Martin Industries, Inc. (the "Borrower") and AmSouth Bank (the
"Lender"), as of ___________, the Borrower hereby certifies to the Lender as
follows:

<TABLE>
<S>     <C>                                                             <C>                     <C>


1.       Net Outstanding Amount of Eligible Accounts
                                                                        $
                                                                         -------------

2.       80% of Net Outstanding Amount of Eligible Accounts
                                                                                                $
                                                                                                 -------------

3.       Net Outstanding Amount of Eligible Dating Accounts
                                                                        $
                                                                         -------------

4.       80% of Net Outstanding Amount of Eligible Dating Accounts
                                                                                                $
                                                                                                 -------------

5.       Collateral value of Eligible Finished Goods Inventory
                                                                        $
                                                                         -------------

6.       35% of collateral value of Eligible Finished Goods Inventory
                                                                                                $
                                                                                                 -------------

7.       Collateral value of Eligible Raw Material Inventory
                                                                        $
                                                                         -------------

8.       28% of collateral value of Eligible Raw Material Inventory
                                                                                                $
                                                                                                 -------------

9.       TOTAL BORROWING BASE                                                                   $
                                                                                                 -------------



10.      Maximum Line of Credit Amount                                                          $
                                                                                                 -------------


11.      Amount Outstanding Under Line of Credit                                                $
                                                                                                 -------------


12.      AMOUNT AVAILABLE UNDER LINE OF CREDIT                                                  $
                                                                                                 -------------
</TABLE>


                                       8
<PAGE>


Borrower:

MARTIN INDUSTRIES, INC.

By:
   ------------------------
Its:
    -----------------------


                                       9