As filed with the Securities and Exchange Commission on October 16, 1997

                                                  REGISTRATION NO. 333-

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933


                            COMFORT SYSTEMS USA, INC.
             (Exact name of registrant as specified in its charter)

            DELAWARE                                           76-0526487
  (State or other jurisdiction                              (I.R.S. Employer
of incorporation or organization)                        Identification Number)

                                 THREE RIVERWAY
                                    SUITE 200
                              HOUSTON, TEXAS 77056
                                 (713) 965-9101
  (Address, including zip code, and telephone number, including area code, of
                   registrant's principal executive offices)

                            COMFORT SYSTEMS USA, INC.
                          1997 LONG-TERM INCENTIVE PLAN

                            COMFORT SYSTEMS USA, INC.
                     1997 NON-EMPLOYEE DIRECTORS' STOCK PLAN

                            COMFORT SYSTEMS USA, INC.
                        1998 EMPLOYEE STOCK PURCHASE PLAN
                              (Full Title of Plans)

                                FRED M. FERREIRA
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                            COMFORT SYSTEMS USA, INC.
                                 THREE RIVERWAY
                                    SUITE 200
                              HOUSTON, TEXAS 77056
                                 (713) 830-9600
           (Name, address, including zip code, and telephone number,
                   including area code, of agent for service)

                                 WITH COPIES TO:

             WILLIAM D. GUTERMUTH                        WILLIAM GEORGE
         BRACEWELL & PATTERSON, L.L.P.              COMFORT SYSTEMS USA, INC.
          SOUTH TOWER PENNZOIL PLACE                     THREE RIVERWAY
       711 LOUISIANA STREET, SUITE 2900                     SUITE 200
           HOUSTON, TEXAS 77002-2781                  HOUSTON, TEXAS 77056
                (713) 221-1316                           (713) 830-9600

                                CALCULATION OF REGISTRATION FEE


=================================================================================================================
                                                              PROPOSED
                                                               MAXIMUM                PROPOSED        AMOUNT OF
           TITLE OF                       AMOUNT TO            OFFERING           MAXIMUM AGGREGATE  REGISTRATION
  SECURITIES TO BE REGISTERED        BE REGISTERED(1)(2)    PRICE PER SHARE (3)   OFFERING PRICE(3)      FEE
- -----------------------------------------------------------------------------------------------------------------
                                                                                          
Common Stock, par value $.01 per share   3,570,000              $18.8125          $67,160,626         $20,352
=================================================================================================================

(1) Pursuant to Rule 457(h)(1), the registration fee is calculated with respect
    to the maximum number of the registrant's securities issuable under the
    Comfort Systems USA, Inc. 1997 Long-Term Incentive Plan (the "Incentive
    Plan"), the Comfort Systems USA, Inc. 1997 Non-Employee Directors' Stock
    Plan (the "Director Plan") and the Comfort Systems USA, Inc. 1998 Employee
    Stock Purchase Plan (the "Stock Purchase Plan") (the Incentive Plan ,
    Director Plan, and Stock Purchase Plan are collectively referred to herein
    as the "Plans").

(2) The amount of securities registered hereby may exceed 3,570,000 shares of
    Common Stock. The total number of shares of Common Stock subject to
    incentive awards under the Director Plan is 250,000, subject to adjustment
    from time to time as a result of certain anti-dilution provisions contained
    in such plan. The total number of shares of Common Stock subject to
    incentive awards under the Incentive Plan is the greater of (i) 2,500,000
    and (ii) 13% of the total number of shares of Common Stock outstanding at
    the time an incentive award is granted. In addition, the number of shares
    issuable under the Incentive Plan is subject to adjustment from time to time
    as a result of certain anti-dilution provisions contained in such plan. The
    total number of shares of Common Stock that may be issued under the Stock
    Purchase Plan is 300,000, subject to adjustment from time to time as a
    result of certain anti-dilution provisions contained in such plan. Pursuant
    to Rule 416(a) of the Securities Act of 1933, as amended (the "Act"), this
    Registration Statement is deemed to cover these adjustments in the total
    number of shares available under the Plans, which adjustments are
    indeterminate at this time.

(3) Pursuant to Rule 457(c), the registration fee for these shares is calculated
    based on the average of the high and low sales price per share of the Common
    Stock, as reported by the New York Stock Exchange on October 13, 1997.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.         INCORPORATION OF DOCUMENTS BY REFERENCE.

    Comfort Systems USA, Inc., a Delaware company ("the Company"), hereby
incorporates by reference into this registration statement (the "Registration
Statement"): (i) the Company's prospectus filed pursuant to Rule 424(b) of the
Securities Act of 1933, as amended, on July 31, 1997, as part of its
Registration Statement on Form S-1; (ii) the description of the Company's Common
Stock contained in the Company's Form 8-A, filed May 19, 1997; and (iii) all
other reports filed by the Company pursuant to Section 13(a) or 15(d) of the
Securities and Exchange Act of 1934, as amended, since December 31, 1996.

    All documents filed by the Company with the Commission pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities and Exchange Act of 1934, as
amended, subsequent to the filing date of this Registration Statement and prior
to the filing of a post-effective amendment to this Registration Statement which
indicates that all securities offered have been sold or which deregisters all
securities then remaining unsold shall be deemed to be incorporated by reference
in this Registration Statement and to be a part hereof from the date of filing
of such documents.

    The Company will provide, without charge, to each participant in the
Company's 1997 Long-Term Incentive Plan, 1997 Non-Employee Directors' Stock Plan
and 1998 Employee Stock Purchase Plan, on written or oral request of such
person, a copy (without exhibits, unless such exhibits are specifically
incorporated by reference) of any or all of the documents incorporated by
reference pursuant to this Item 3. All such requests should be directed to
Comfort Systems USA, Inc., Three Riverway, Suite 200, Houston, Texas 77056,
Attention: General Counsel, phone number (713) 965-9101.

ITEM 4.        DESCRIPTION OF SECURITIES.

    Not applicable.

ITEM 5.        INTERESTS OF NAMED EXPERTS AND COUNSEL.

    Not applicable.

ITEM 6.        INDEMNIFICATION OF DIRECTORS AND OFFICERS.

    Section 145 of the Delaware General Corporation Law (the "DGCL") permits a
corporation to indemnify any person who was or is a party or is threatened to be
made a party to any threatened, pending or completed action, suit or proceeding,
whether civil, criminal, administrative or investigative, by reason of the fact
that he is or was a director, officer, employee or agent of the corporation or
is or was serving at the request of the corporation as a director, officer,
employee or agent of another corporation, partnership, joint venture, trust or
other enterprise, against expenses, judgments, fines and amounts paid in
settlement actually and reasonably incurred by him in connection with such
action.

    In an action brought to obtain a judgment in the corporation's favor,
whether by the corporation itself or derivatively by a stockholder, the
corporation may only indemnify for expenses, including attorney's fees, actually
and reasonably incurred in connection with the defense or settlement of such
action, and the corporation may not indemnify for amounts paid in satisfaction
of a judgment or in settlement of the claim. In any such action, no
indemnification may be paid in respect of any claim, issue or matter as to which
such person shall have been adjudged liable to the corporation except as
otherwise approved by the Delaware Court of Chancery or the court in which the
claim was

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brought. In any other type of proceeding, the indemnification may extend to
judgments, fines and amounts paid in settlement, actually and reasonably
incurred in connection with such other proceeding, as well as to expenses.

    The statute does not permit indemnification unless the person seeking
indemnification has acted in good faith and in a manner reasonably believed to
be in, or not opposed to, the best interests of the corporation and, in the case
of criminal actions or proceedings, the person had no reasonable cause to
believe his conduct was unlawful. The statute contains additional limitations
applicable to criminal actions and to actions brought by or in the name of the
corporation. The determination as to whether an employee or agent (who is not
then a director or officer of the corporation) seeking indemnification has met
the required standard of conduct may be made by any person or persons having
authority to act on the matter. The determination as to whether a director or
officer seeking indemnification has met the required standard be made (1) by a
majority vote of a quorum of disinterested members of the board of directors,
(or a committee thereof) (2) by independent legal counsel in a written opinion,
if such a quorum does not exist or if the disinterested directors so direct, or
(3) by the stockholders.

    The Company's Certificate of Incorporation requires the Company to indemnify
its directors and officers to the fullest extent permitted by Section 145 of the
DGCL. In addition, the Company maintains liability insurance for its directors
and officers.

ITEM 7.        EXEMPTION FROM REGISTRATION CLAIMED.

    Not applicable.

ITEM 8.        EXHIBITS.


    4.1 The Comfort Systems USA, Inc. 1997 Incentive Plan (incorporated by
        reference to the Company's Registration Statement on Form S-1 (File No.
        333-24021), filed March 26, 1997)

    4.2 The Comfort Systems USA, Inc. 1997 Non-Employee Director Plan
        (incorporated by reference to the Company's Registration Statement on
        Form S-1 (File No. 333-24021), filed March 26, 1997)

    4.3 The Comfort Systems USA, Inc. 1998 Employee Stock Purchase Plan

    5.1 Opinion of Bracewell & Patterson, L.L.P.

    23.1 Consent of Arthur Andersen LLP

    23.2 Consent of Bracewell & Patterson, L.L.P. (included in Exhibit 5.1)

    24.1 Power of Attorney (included on the signature page hereto)

ITEM 9.        UNDERTAKINGS.

    A. UNDERTAKING TO UPDATE

            The undersigned registrant hereby undertakes:

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                (1) To file, during any period in which offers or sales are
            being made, a post-effective amendment to this registration
            statement:

                    (i) To include any prospectus required by section 10(a)(3)
                of the Securities Act of 1933;

                    (ii) To reflect in the prospectus any facts or events
                arising after the effective date of the registration statement
                (or the most recent post-effective amendment thereof) which,
                individually or in the aggregate, represent a fundamental change
                in the information set forth in this Registration Statement.
                Notwithstanding the foregoing, any increase or decrease in
                volume of securities offered (if the total dollar value of
                securities offered would not exceed that which was registered)
                and any deviation from the low or high and of the estimated
                maximum offering range may be reflected in the form of a
                prospectus filed with the Commission pursuant to Rule 424(b) if,
                in the aggregate, the changes in volume and price represent no
                more than a 20 percent change in the maximum aggregate offering
                price set forth in the "Calculation of Registration Fee" table
                in the effective registration statement.

                    (iii) To include any material information with respect to
                the plan of distribution not previously disclosed in the
                registration statement or any material change to such
                information in this Registration Statement;

            PROVIDED, HOWEVER, that paragraphs (A)(1)(i) and (A)(1)(ii) of this
            section do not apply if the information required to be included in a
            post-effective amendment by those paragraphs is contained in
            periodic reports filed by the registrant pursuant to Section 13 or
            Section 15(d) of the Exchange Act, that are incorporated by
            reference in this Registration Statement.

                (2) That, for the purpose of determining any liability under the
            Securities Act, each such post-effective amendment shall be deemed
            to be a new registration statement relating to the securities
            offered therein, and the offering of such securities at that time
            shall be deemed to be the initial bona fide offering thereof.

                (3) To remove from registration by means of a post-effective
            amendment any of the securities being registered which remain unsold
            at the termination of the offering.

    B. UNDERTAKING WITH RESPECT TO DOCUMENTS INCORPORATED BY REFERENCE

            The undersigned registrant hereby undertakes that, for purposes of
            determining any liability under the Securities Act of 1933, each
            filing of the registrant's annual report pursuant to Section 13(a)
            or Section 15(d) of the Securities Exchange Act of 1934 that is
            incorporated by reference in the registration statement shall be
            deemed to be a new registration statement relating to the securities
            offered therein, and the offering of such securities at that time
            shall be deemed to be the initial bona fide offering thereof.

    C. UNDERTAKING WITH RESPECT TO INDEMNIFICATION

                Insofar as indemnification for liabilities arising under the
            Securities Act may be permitted to directors, officers and
            controlling persons of the registrant pursuant to the foregoing
            provisions, or otherwise, the registrant has been advised that in
            the opinion of the Securities and Exchange Commission such
            indemnification is against public policy as expressed in the Act and
            is, therefore, unenforceable. In the event that a claim for
            indemnification against such liabilities (other than the

                                      II-3

            payment by the registrant of expenses incurred or paid by a
            director, officer or controlling person of the registrant in the
            successful defense of any action, suit or proceeding) is asserted by
            such director, officer or controlling person in connection with the
            securities being registered, the registrant will, unless in the
            opinion of its counsel the matter has been settled by controlling
            precedent, submit to a court of appropriate jurisdiction the
            question whether such indemnification by it is against public policy
            as expressed in the Act and will be governed by the final
            adjudication of such issue.







                            [SIGNATURE PAGE FOLLOWS]

                                     II-4

                                   SIGNATURES

    In accordance with the requirements of the Securities Act of 1933, as
amended, the registrant certifies that it has reasonable grounds to believe that
it meets all of the requirements of filing on Form S-8 and has duly authorized
this Registration Statement to be signed on its behalf by the undersigned, in
the City of Houston, State of Texas on October 14, 1997.

                                                   COMFORT SYSTEMS USA, INC.


                                                   By: /S/ FRED M. FERREIRA
                                                          Fred M. Ferreira,
                                                          PRESIDENT AND CHIEF
                                                          EXECUTIVE OFFICER

    We, the undersigned directors and officers of Comfort Systems USA, Inc.,
constitute and appoint Fred M. Ferreira or William George, III , or either of
them, our true and lawful attorneys and agents, to do any and all acts and
things in our name and on our behalf in our capacities as directors and
officers, and to execute any and all instruments for us and in our names in the
capacities indicated below, which said attorneys and agents, or either of them,
may deem necessary or advisable to enable said corporation to comply with the
Securities Act of 1933, as amended, and any rules, regulations and requirements
of the Securities and Exchange Commission, in connection with the filing of this
Registration Statement, including specifically without limitation, power and
authority to sign for any of us, in our names in the capacities indicated below,
any and all amendments hereto; and we do each hereby ratify and confirm all that
the said attorneys and agents, or either of them, shall do or cause to be done
by virtue hereof.

    Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the date indicated on October 14, 1997.


          SIGNATURE                                    TITLE

/S/ FRED M. FERREIRA                   Chairman of the Board, Chief Executive
    Fred M. Ferreira                   Officer and President

/S/ J. GORDON BEITTENMILLER            Senior Vice President, Chief Financial
    J. Gordon Beittenmiller            Officer and Director

/S/ MICHAEL NOTHUM, JR.                Director
    Michael Nothum, Jr.

______________________________         Director
    Brian S. Atlas

/S/ THOMAS J. BEATY                    Director
    Thomas J. Beaty

/S/ ROBERT R. COOK                     Director
    Robert R. Cook

/S/ ALFRED J. GIARDENELLI              Director
    Alfred J. Giardenelli, Jr.

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/S/ CHARLES W. KLAPPERICH              Director
    Charles W. Klapperich

/S/ SAMUEL M. LAWRENCE, III            Director
    Samuel M. Lawrence, III

/S/ JOHN C. PHILLIPS                   Director
    John C. Phillips

/S/ ROBERT J. POWERS                   Director
    Robert J. Powers

/S/ STEVEN S. HARTER                   Director
    Steven S. Harter

_____________________________          Director
    Larry Martin

_____________________________          Director
    John Mercadante, Jr.

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