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                                                                    EXHIBIT 5.1

                                           , 1999
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Board of Directors
American Plumbing and Mechanical, Inc.
1502 Augusta, Suite 425
Houston, Texas 77057

Ladies and Gentlemen:

                  We have acted as counsel to American Plumbing & Mechanical,
Inc., a Delaware corporation (the "Company"), and are delivering this opinion
in connection with the Company's Registration Statement on Form S-4 (the
"Registration Statement") relating to the registration under the Securities Act
of 1933, as amended (the "Securities Act"), of the offer by the Company to
exchange up to $125,000,000 aggregate principal amount of its 115/8% Senior
Subordinated Notes Due 2008, Series B (the "Exchange Notes") for its existing
115/8% Senior Subordinated Notes Due 2008, Series A (the "Existing Notes"). The
Exchange Notes are proposed to be issued in accordance with the provisions of
the indenture (the "Indenture"), dated as of May 19, 1999, between the Company,
the guarantors named therein (the "Guarantors") and State Street Bank and Trust
Company, as Trustee.

                  In arriving at the opinions expressed below, we have examined
the Registration Statement, the Prospectus contained therein, the Indenture
which is filed as an exhibit to the Registration Statement, and the originals
or copies certified or otherwise identified to our satisfaction of such other
instruments and other certificates of public officials and officers and
representatives of the Company. In all such examinations and for purposes of
our opinions set forth below, we have, with your approval and without
independent investigation, assumed the genuineness of all signatures, the legal
capacity of all natural persons, the authenticity and completeness of all
documents submitted to us as originals, the conformity to the authentic
original documents of all documents submitted to us as copies and that all
documents in respect of which forms were filed with the Securities and Exchange
Commission as exhibits to the Registration Statement will conform in all
material respects to the forms thereof that we have examined. In addition, as
the basis for the opinion hereinafter expressed, we have examined such
statutes, regulations, corporate records and documents, certificates of
corporate and public officials and other instruments as we have deemed
necessary or advisable for the purposes of this opinion.

                  Based on the foregoing, and having due regard for such legal
considerations as we deem relevant, and subject to the qualifications and
limitations set forth below, we are of the opinion that the Exchange Notes and
the guarantee of each of the Guarantors (the "Guarantees"), (a) when



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Board of Directors
American Plumbing and Mechanical, Inc.
             , 1999
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the Notes have been exchanged in the manner described in the Registration
Statement, (b) when the Exchange Notes have been duly executed, authenticated,
issued and delivered in accordance with the terms of the Indenture, (c) when
the Indenture has been duly qualified under the Trust Indenture Act of 1939, as
amended, and (d) when applicable provisions of "blue sky" laws have been
complied with, will constitute valid and binding obligations of the Company and
the Guarantors, as applicable, enforceable against the Company and the
Guarantors, as applicable, in accordance with their terms, under the laws of
the State of New York which are expressed to govern the same, except as the
enforcement thereof may be limited by (a) bankruptcy, insolvency,
reorganization, moratorium (including, without limitation, all laws relating to
fraudulent transfers), (b) other similar laws relating to or affecting
enforcement of creditors' rights generally, (c) general principles of equity
(regardless of whether enforcement is considered in a proceeding in equity or
at law) and (d) limitations on the waiver of rights under usury laws, and will
be entitled to the benefits of the Indenture.

                  This opinion is limited in all respects to the laws of the
State of Texas, the State of New York and the Delaware General Corporation Law.
We express no opinion as to, and for the purposes of the opinions set forth
herein, we have conducted no investigation of, and do not purport to be experts
on, any other laws. With respect to each Guarantor which was not organized
under the laws of the State of Texas or the State of Delaware, we have assumed
that the laws of the jurisdiction, organization or formation of such Guarantor
with respect to matters of authorization, execution and delivery do not differ
in any material respect from the laws of the State of Texas in those regards
and have undertaken no investigation of the laws of any jurisdiction or their
effect, if any, on any legal conclusion herein expressed other than, the laws
of the State of Texas, the State of New York and the Delaware General
Corporation Law. We hereby consent to the use of this opinion as an exhibit to
the Registration Statement.

                                       Very truly yours,