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                                                                    EXHIBIT 99.3

                      AMERICAN PLUMBING & MECHANICAL, INC.

                                OFFER TO EXCHANGE
                                       its
              11 5/8% Senior Subordinated Notes Due 2008, Series B
                             for any and all of its
              11 5/8% Senior Subordinated Notes due 2008, Series A


To Our Clients:

         Enclosed for your consideration are the Prospectus dated __________,
1999 (the "Prospectus") and the related Letter of Transmittal (which together
with the Prospectus constitute the "Exchange Offer") in connection with the
offer by American Plumbing & Mechanical, Inc., a Delaware corporation (the
"Company"), to exchange its outstanding 115/8% Senior Subordinated Notes due
2008, Series A (the "Exchange Notes") for any and all of the outstanding 115/8%
Senior Subordinated Notes due 2008, Series B (the "Old Notes"), upon the terms
and subject to the conditions set forth in the Exchange Offer.

         We are the Registered Holders of Old Notes held for your account. An
exchange of the Old Notes can be made only by us as the Registered Holders and
pursuant to your instructions. The Letter of Transmittal is furnished to you for
your information only and cannot be used by you to exchange the Old Notes held
by us for your account. The Exchange Offer provides a procedure for holders to
tender by means of guaranteed delivery.

         We request information as to whether you wish us to exchange any or all
of the Old Notes held by us for your account upon the terms and subject to the
conditions of the Exchange Offer.

         Your attention is directed to the following:

              1. The Exchange Notes will be exchanged for the Old Notes at the
         rate of $1,000 principal amount of Exchange Notes for each $1,000
         principal amount of Old Notes. Interest on the Notes will accrue at the
         rate of 115/8% per annum and will be payable semi-annually on each
         April 15 and October 15 commencing October 15, 1999, to the holders of
         record of Notes at the close of business on the April 1 and October 1,
         respectively, immediately preceding such interest payment date.
         Interest on the Notes will accrue from the most recent date to which
         interest has been paid or, if no interest has been paid, from the
         original date of issuance. Interest will be computed on the basis of a
         360-day year comprised of twelve 30-day months. The form and terms of
         the Exchange Notes are identical in all material respects to the form
         and terms of the Old Notes, except that (i) the offering of the
         Exchange Notes has been registered under the Securities Act of 1933, as
         amended (the "Securities Act"), (ii) the Exchange Notes will not be
         subject to transfer restrictions and (iii) certain provisions relating
         to an increase in the stated interest rate on the Old Notes provided
         for under certain circumstances will be eliminated.

              2. Based on an interpretation by the staff of the Securities and
         Exchange Commission, Exchange Notes issued pursuant to the Exchange
         Offer in exchange for Old Notes may be offered for resale, resold and
         otherwise transferred by holders thereof (other than any such holder
         which is an "affiliate" of the Company within the meaning of Rule 405
         under the Securities Act or a "broker" or "dealer" registered under the
         Securities Exchange Act of 1934, as amended) without compliance with
         the registration and prospectus delivery provisions of the Securities
         Act, provided that such Exchange Notes are acquired in the ordinary
         course of such holders' business and such holders have no arrangement
         or understanding with any person to participate in the distribution of
         such Exchange Notes. See the discussion in the Prospectus under "The
         Exchange Offer--Purpose and Effect of the Exchange Offer."

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              3. The Exchange Offer is not conditioned on any minimum principal
         amount of Old Notes being tendered.

              4. Notwithstanding any other term of the Exchange Offer, the
         Company will not be required to accept for exchange, or exchange
         Exchange Notes for, any Old Notes not theretofore accepted for
         exchange, and may terminate or amend the Exchange Offer as provided
         herein before the acceptance of such Old Notes, if any of the
         conditions described in the Prospectus under "The Exchange
         Offer--Conditions to the Exchange Offer" exist.

              5. Tendered Old Notes may be withdrawn at any time prior to
         5:00 p.m., New York City time, on , 1999.

              6. Any transfer taxes applicable to the exchange of the Old Notes
         pursuant to the Offer will be paid by the Company, except as otherwise
         provided in the Prospectus under "The Exchange Offer--Solicitation of
         Tenders; Fees and Expenses" and in Instruction 9 of the Letter of
         Transmittal.

         If you wish to have us tender any or all of your Old Notes, please so
instruct us by completing, detaching and returning to us the instruction form
attached hereto. An envelope to return your instructions is enclosed. If you
authorize a tender of your Old Notes, the entire principal amount of Old Notes
held for your account will be tendered unless otherwise specified on the
instruction form. Your instructions should be forwarded to us in ample time to
permit us to submit a tender on your behalf by the Expiration Date.

         The Exchange Offer is not being made to, nor will tenders be accepted
from or on behalf of, holders of the Old Notes in any jurisdiction in which the
making of the Exchange Offer or acceptance thereof would not be in compliance
with the laws of such jurisdiction or would otherwise not be in compliance with
any provision of any applicable security law.


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