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                                                                 Exhibit (10)(r)



                                 SIXTH AMENDMENT
                                       TO
                                CREDIT AGREEMENT


         This Sixth Amendment to Credit Agreement (this "Amendment"), dated as
of June 25, 1998, is entered into by and among LESCO, INC., an Ohio corporation
("Borrower"), NATIONAL CITY BANK, NBD BANK, and PNC BANK, NATIONAL ASSOCIATION
(together the "Banks") and NATIONAL CITY BANK IN ITS CAPACITY AS AGENT of the
Banks ("Agent") for the purposes of the Credit Agreement referred to below and
the Related Writings.

                                   WITNESSETH:

         WHEREAS, the parties have entered into a Credit Agreement originally
dated as of September 30, 1994 (as amended from time to time, the "Credit
Agreement"; all terms used in the Credit Agreement being used herein with the
same meaning), which sets forth the terms and conditions upon which Banks have
advanced term loans to Borrower and upon which Borrower may obtain revolving
loans from time to time; and

         WHEREAS, the parties desire to amend the Credit Agreement to modify the
negative covenant concerning borrowings contained in subsection 3D.03 to permit
a private placement of unsecured debt in the amount of $50,000,000;

         NOW, THEREFORE, in consideration of the premises above and the mutual
covenants and agreements contained herein and for other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
parties agree as follows:

SECTION I - AMENDMENT TO CREDIT AGREEMENT
            -----------------------------

         Subsection 3D.03 of the Credit Agreement is hereby amended and restated
to read as follows:

      "3D.03 BORROWINGS -- No Company will create, assume or have outstanding at
      any time any indebtedness for borrowed money or any Funded Indebtedness of
      any kind; PROVIDED, that this subsection shall not apply to

                 (i) the Subject Indebtedness,

                 (ii) any Subordinated indebtedness owing by Borrower,

                 (iii) any borrowing owing by a Company to a Company,

                 (iv) any existing or future indebtedness secured by a purchase
                 money security interest permitted by subsection 3D.04 or
                 incurred under a lease permitted by subsection 3D.04,

                 (v) the industrial development revenue bonds issued in the
                 aggregate principal amount of approximately five million eight
                 hundred and seventy-five thousand dollars ($5,875,000) in
                 connection with Borrower's acquisition of a plant in Martin's
                 Ferry, Ohio, or the loan obtained in connection therewith from
                 the State of Ohio in the principal sum of one million dollars
                 ($1,000,000),

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                 (vi) any existing indebtedness fully disclosed in Borrower's
                 Most Recent 4A.04 Financial Statements or in the Supplemental
                 Schedule or any renewal or extension thereof in whole or in
                 part;

                 (vii) unsecured indebtedness initially privately placed to The
                 Canada Life Assurance Company of America, Pacific Life
                 Insurance Company, Provident Mutual Life Insurance Company,
                 Providentmutual Life and Annuity Company of America, Phoenix
                 American Life Insurance Company, and The Travelers Insurance
                 Company (and other affiliates of such entities or their
                 respective nominees) in the principal amount of $50,000,000; or

                 (viii) any other indebtedness so long as (a) the same is
                 unsecured and (b) the aggregate unpaid principal amount of such
                 other indebtedness does not exceed twenty million dollars
                 ($20,000,000) at any time."


SECTION II - CONDITIONS PRECEDENT
             --------------------

         It is a condition precedent to the effectiveness of this Amendment
that, prior to or on the date hereof, such documents as Agent may reasonably
request to implement this Amendment and the transactions contemplated hereby
shall have been delivered to Agent (in form and substance acceptable to Agent).

SECTION III - REPRESENTATIONS AND WARRANTIES
              ------------------------------

         Borrower hereby represents and warrants to each of the other parties to
this Amendment that

         (A) none of the representations and warranties made in the Credit
         Agreement has ceased to be true and complete in any material respect as
         of the date hereof; and

         (B) as of the date hereof no "Default Under This Agreement" has
         occurred that is continuing.

SECTION IV - ACKNOWLEDGMENTS CONCERNING OUTSTANDING LOANS
             --------------------------------------------

         Borrower acknowledges and agrees that, as of the date hereof, all of
Borrower's outstanding loan obligations to Banks are owed without any offset,
deduction, defense, claim or counterclaim of any nature whatsoever. Borrower
authorizes each Bank to share all credit and financial information relating to
Borrower with such Bank's parent company and with any subsidiary or affiliate
company of such Bank or of such Bank's parent company.

SECTION V - REFERENCES
            ----------

         On and after the effective date 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 Subject
Notes or other Related Writings to the "Credit Agreement", "thereof", or words
of like import referring to the Credit Agreement shall mean and refer to the
Credit Agreement as previously amended and as amended hereby. The Credit
Agreement, as previously amended and as amended by this Amendment, is and shall
continue to be in full force and effect and is hereby ratified and confirmed in
all respects. The execution, delivery and effectiveness of this Amendment shall
not operate as a waiver of any right, power or remedy of Agent or Banks under
the Credit Agreement or constitute a waiver of any provision of the Credit
Agreement except as specifically set forth herein.

SECTION VI - COUNTERPARTS AND GOVERNING LAW
             ------------------------------


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         This Amendment may be executed in any number of counterparts, each
counterpart to be executed by one or more of the parties but, when taken
together, all counterparts shall constitute one agreement. This Amendment, and
the respective rights and obligations of the parties hereto, shall be construed
in accordance with and governed by Ohio law.

         IN WITNESS WHEREOF, the Borrower, Agent and the Banks have caused this
Amendment to be executed by their authorized officers as of the date and year
first above written.

Address:                                    LESCO, INC.
  20005 Lake Road
  Rocky River, Ohio  44116                  By:              /ss/
                                                --------------------------------
                                            Printed Name:   Ware H. Grove
                                            Title:   Vice President / Chief 
                                                      Financial Officer


Address:                                    NATIONAL CITY BANK, AGENT
  1900 East Ninth Street
  Attn: Multinational Division              By:              /ss/
  Cleveland, Ohio 44114-3484                    --------------------------------
                                            Printed Name:   Terri L. Cable
                                            Title:   Senior Vice President
                                            

Address:                                    NATIONAL CITY BANK
  1900 East Ninth Street
  Attn: Multinational Division              By:              /ss/
  Cleveland, Ohio 44114-3484                    --------------------------------
                                            Printed Name:   Terri L. Cable
                                            Title: Senior Vice President  
                                            

Address:                                    PNC BANK, NATIONAL ASSOCIATION
  1375 East Ninth Street
  Suite 1250                                By:              /ss/
  Cleveland, Ohio  44114-3103                    -------------------------------
                                            Printed Name:   David Williams
                                            Title:   Vice President       
                                            

Address:                                    NBD BANK
  611 Woodward Avenue
  Detroit, Michigan  48226                  By:          /ss/               
                                                --------------------------------
                                            Printed Name:   Paul DeMelo
                                            Title:   Vice President


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