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Exhibit 10.10

EMPLOYMENT AGREEMENT

        THIS EMPLOYMENT AGREEMENT (this "Agreement") between COMFORT SYSTEMS
USA, INC., a Delaware corporation (referred to herein individually as "Comfort"
and collectively with its subsidiaries and affiliates as the "Company"), and
Thomas Tanner ("Executive") is entered into and effective as of the 1st day of
January, 2004. This Agreement supersedes any other employment agreements or
understandings, written or oral, between the Company and Executive.

R E C I T A L S

        The following statements are true and correct:

        As of the date of this Agreement, the Company is engaged in the business
of mechanical contracting services, including heating, ventilation and air
conditioning, plumbing, piping, electrical and related services ("Services").

        Executive is employed hereunder by the Company in a confidential
relationship wherein Executive, in the course of Executive's employment with the
Company, has and will continue to become familiar with and aware of information
as to the Company's and its customers' specific manner of doing business,
including the processes, techniques and trade secrets utilized by the Company,
and future plans with respect thereto, all of which has been and will be
established and maintained at great expense to the Company. This information is
a trade secret and constitutes the valuable goodwill of the Company.

        NOW, THEREFORE, in consideration of the mutual promises, terms,
covenants and conditions set forth herein and the performance of each, the
Company and Executive hereby agree as follows:

A G R E E M E N T S

        1.     Employment and Duties.

        (a)   The Company hereby employs Executive in an executive position and
Executive hereby accepts this employment upon the terms and conditions herein
contained. Executive agrees to devote substantially all of Executive's business
time, attention and efforts to promote and further the business of the Company.

        (b)   Executive shall faithfully adhere to, execute and fulfill all
lawful policies established by the Company, including the Company's Corporate
Compliance Policy.

        (c)   Executive shall not, during the term of Executive's employment
hereunder, be engaged in any other business activity pursued for gain, profit or
other pecuniary advantage if such activity interferes in any material respect
with Executive's duties and responsibilities hereunder. The foregoing
limitations shall not be construed as prohibiting Executive from making personal
investments in such form or manner as will neither require Executive's services
in the operation or affairs of the companies or enterprises in which such
investments are made nor violate the terms of Section 4 hereof.

        2.     Compensation.    For all services rendered by Executive, the
Company shall compensate Executive as follows:

        (a)   Base Salary. Effective the date hereof, the base salary payable to
Executive shall be $195,000 per year, payable on a regular basis in accordance
with the Company's standard payroll procedures, but not less often than monthly.

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        (b)   Executive Perquisites, Benefits and Other Compensation. Executive
shall be entitled to receive additional benefits and compensation from the
Company in such form and to the extent specified below:

          (i)  Coverage, subject to contributions required of employees
generally, for Executive and Executive's dependent family members under health,
hospitalization, disability, dental, life and other insurance plans that the
Company may have in effect from time to time for the benefit of its employees.

         (ii)  Reimbursement for all business travel and other out-of-pocket
expenses reasonably incurred by Executive in the performance of Executive's
services pursuant to this Agreement. Reimbursable expenses shall be
appropriately documented in reasonable detail by Executive, and shall be in a
format consistent with the Company's expense reporting policy.

        3.     Confidentiality.

        (a)   Confidential Information. As used herein, the term "Confidential
Information" means any information, technical data or know-how of the Company,
including, but not limited to, that which relates to customers, business
affairs, business plans, financial matters, financial plans and projections,
pending and proposed acquisitions, operational and hiring matters, contracts and
agreements, marketing, sales and pricing, prospects of the Company, and any
information, technical data or know-how that contain or reflect any of the
foregoing, whether prepared by the Company, Executive or any other person or
entity; provided, however, that the term "Confidential Information" shall not
include information, technical data or know-how that Executive can demonstrate
is generally available to the public not as a result of any breach of this
Agreement by Executive.

        (b)   No Disclosure. Except in the performance of Executive's duties as
an employee of the Company, Executive will not, during or after the term of
Executive's engagement with the Company, disclose to any person or entity or
use, for any reason whatsoever, any Confidential Information.

        4.     Non-Competition Agreement.

        (a)   Competition. Executive will not, during the period of Executive's
employment by or with the Company, and for a period of twelve months immediately
following the termination of Executive's employment, for any reason whatsoever,
directly or indirectly, on behalf of Executive or on behalf of or in conjunction
with any other person, company, partnership, corporation or business of whatever
nature:

          (i)  engage, as an officer, director, shareholder, owner, partner,
joint venturer, or in a managerial capacity, whether as an employee, independent
contractor, consultant or advisor, or as a sales representative, or make or
guarantee loans or invest in or for any business engaged in Services in
competition with the Company within 100 miles of where the Company conducts or
has conducted business during the Term (the "Territory");

         (ii)  call upon any person who is, at that time, within the Territory,
an employee of the Company in a technical, managerial or sales capacity for the
purpose or with the intent of enticing such employee away from or out of the
employ of the Company;

        (iii)  call upon any person or entity which is, at that time, or which
has been, within two (2) years prior to that time, a customer of the Company for
the purpose of soliciting or selling Services;

        (iv)  call upon any prospective acquisition candidate, on Executive's
own behalf or on behalf of any competitor, which candidate was either called
upon by the Executive on behalf of the Company or for which the Executive made
an acquisition analysis on behalf of the Company for the purpose of acquiring
such entity.

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Notwithstanding the above, the foregoing covenants shall not be deemed to
prohibit Executive from acquiring as an investment not more than one percent
(1%) of the capital stock of a competing business whose stock is traded on a
national securities exchange or on an over-the-counter or similar market.

        (b)   No Violation. It is specifically agreed that the period during
which the agreements and covenants of Executive made in this Section 4 shall be
effective shall be computed by excluding from such computation any time during
which Executive is in violation of any provision of this Section 4.

        5.     Term; Termination; Rights on Termination.    The term of this
Agreement shall begin on the date hereof and continue for two (2) (the "Term"),
unless terminated sooner as herein provided. Beginning on the second anniversary
and thereafter on each anniversary this Agreement shall renew for consecutive
one-year terms unless either party shall give the other notice at least 30 days
prior to such anniversary. This Agreement and Executive's employment may be
terminated in any one of the following ways:

        (a)   Death. The death of Executive shall immediately terminate this
Agreement with no severance compensation due to Executive's estate.

        (b)   Disability. If, as a result of incapacity due to physical or
mental illness or injury, Executive shall have been absent from Executive's
full-time duties hereunder for four (4) consecutive months, then thirty
(30) days after receiving written notice (which notice may occur before or after
the end of such four (4) month period, but which shall not be effective earlier
than the last day of such four (4) month period), the Company may terminate
Executive's employment hereunder, provided Executive is unable to resume
Executive's full-time duties at the conclusion of such notice period. In the
event this Agreement is terminated as a result of Executive's disability,
Executive shall receive from the Company Executive's base salary at the rate
then in effect for the lesser of the time period remaining under the Term of
this Agreement or for one (1) year, and such amount shall be payable during such
period in a manner consistent with Company's standard pay practices. The amount
payable hereunder shall be decreased by the amount of benefits otherwise
actually paid by the Company to Executive or on Executive's behalf or under any
insurance procured by the Company.

        (c)   Good Cause. The Company may terminate this Agreement ten (10) days
after written notice to Executive for good cause, which shall include any of the
following: (i) Executive's willful or material breach of this Agreement;
(ii) Executive's failure to perform any of his material duties following notice
by the Company to Executive of such improper performance and Executive's failure
to correct the improper performance to the satisfaction of the Company within a
reasonable time; (iii) Executive's gross negligence in the performance or
intentional nonperformance of any of Executive's material duties and
responsibilities hereunder; (iv) Executive's willful dishonesty, fraud or
misconduct with respect to the business or affairs of the Company or any other
member of the Comfort Group; (v) Executive's conviction of a felony crime;
(vi) Executive's confirmed positive illegal drug test result; (vii) sexual
harassment by Executive; or (viii) willful or material failure by Executive to
comply with Comfort's Corporate Compliance Policy or other Company policies. In
the event of a termination for good cause, as enumerated above, Executive shall
have no right to any severance compensation.

        (d)   Without Cause. At any time after the commencement of Executive's
employment, Executive or the Company may, without cause, terminate this
Agreement and Executive's employment, effective thirty (30) days after receipt
of written notice. Should Executive be terminated by the Company without cause,
Executive shall receive from the Company Executive's base salary at the rate
then in effect for one (1) year, and such amount shall be payable during such
period in a manner consistent with the Company's standard pay practices.

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        (e)   Change in Control. In addition to the foregoing, Company has
agreed that it will pay to Executive a bonus equal to one year of base salary
within twenty business days of the definitive and final closing of any change of
control of Comfort Systems USA, Inc. (a transaction that results in the sale of
a majority of the Comfort's voting capital stock or substantially all of
Comfort's assets).

        6.     Return of Company Property.    All records, plans, manuals,
"field guides", memoranda, lists, documents, statements and other property
delivered to Executive by or on behalf of the Company, by any customer of the
Company (including but not limited to, any such customers obtained by
Executive), by any acquisition candidate of the Company, and all records
compiled by Executive which pertain to the business or activities of the Company
shall be and remain the property of the Company and shall be subject at all
times to its discretion and control. Likewise, all correspondence with
customers, representatives or acquisition candidates, reports, records, charts,
advertising materials, and any data collected by Executive, or by or on behalf
of the Company or any representative of the Company shall be delivered promptly
to the Company without request by it upon termination of Executive's engagement
with the Company.

        7.     Inventions.    Executive shall disclose promptly to the Company
any and all significant conceptions and ideas for inventions, improvements and
valuable discoveries, whether patentable or not, which are conceived or made by
Executive, solely or jointly with another, during the period of Executive's
employment or within one (1) year thereafter, and which are directly related to
the business or activities of the Company or which Executive conceives as a
result of Executive's employment by the Company. Executive hereby assigns and
agrees to assign all Executive's interests therein to the Company or its
nominee. Whenever requested to do so by the Company, Executive shall execute any
and all applications, assignments or other instruments that the Company shall
deem necessary to apply for and obtain Letters Patent of the United States or
any foreign country or to otherwise protect the Company's interest therein.

        8.     Trade Secrets.    Executive agrees that Executive will not,
during or after the Term, disclose the specific terms of the Company's
relationships or agreements with significant vendors or customers or any other
significant and material trade secret of the Company, whether in existence or
proposed, to any person, firm, partnership, corporation or business for any
reason or purpose whatsoever.

        9.     No Prior Agreements.    Executive hereby represents and warrants
to the Company that the execution of this Agreement by Executive and Executive's
employment by the Company and the performance of Executive's duties hereunder
will not violate or be a breach of any agreement with a former employer, client
or any other person or entity. Further, Executive agrees to indemnify the
Company for any claim, including, but not limited to, attorneys' fees and
expenses of investigation, by any such third party that such third party may now
have or may hereafter come to have against the Company based upon or arising out
of any non-competition agreement, invention or secrecy agreement between
Executive and such third party which was in existence as of the date of this
Agreement.

        10.   Assignment; Binding Effect.    Executive understands that
Executive has been selected for employment by the Company on the basis of
Executive's personal qualifications, experience and skills. Executive agrees,
therefore, that Executive cannot assign all or any portion of Executive's
performance under this Agreement. Executive, Executive's spouse and the estates
of each shall not have any right to encumber or dispose of any right to receive
payments hereunder, it being understood that such payments and the right thereto
are nonassignable and nontransferable; provided, however in the event of the
death of Executive, any payments that Executive is entitled to receive may be
assigned to the beneficiaries of Executive's estate. Subject to the preceding
three (3) sentences and the express provisions of Section 11 below, this
Agreement shall be binding upon, inure to the benefit of and be enforceable by
the parties hereto and their respective heirs, legal representatives, successors
and assigns.

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        11.   Complete Agreement.    Executive has no oral representations,
understandings or agreements with the Company or any of its officers, directors
or representatives covering the same subject matter as this Agreement. This
Agreement is the final, complete and exclusive statement and expression of the
agreement between the Company and Executive and of all the terms of this
Agreement, and it cannot be varied, contradicted or supplemented by evidence of
any prior or contemporaneous oral or written agreements.

        12.   Amendment; Waiver.    This Agreement may not be modified except in
writing signed by the parties, and no term of this Agreement may be waived
except by a writing signed by the party waiving the benefit of such terms. No
waiver by the parties hereto of any default or breach of any term, condition or
covenant of this Agreement shall be deemed to be a waiver of any subsequent
default or breach of the same or any other term, condition or covenant contained
herein.

        13.   Notice.    Whenever any notice is required hereunder, it shall be
given in writing addressed as follows:

    To the Company:   Comfort Systems USA, Inc.
777 Post Oak Boulevard, Ste. 500
Houston, TX 77056
Attention: General Counsel
 
 
To Executive:
 
Thomas Tanner
6862 Claret Circle
Fayetteville, NY 13066

Notice shall be deemed given and effective on the earlier of five (5) days after
the deposit in the U.S. mail of a writing addressed as above and sent first
class mail, certified, return receipt requested, or when actually received.
Either party may change the address for notice by notifying the other party of
such change in accordance with this Section 13.

        14.   Severability; Enforceability.    If any portion of this Agreement
is held invalid or inoperative, the other portions of this Agreement shall be
deemed valid and operative and, so far as is reasonable and possible, effect
shall be given to the intent manifested by the portion held invalid or
inoperative. Moreover, in the event any court of competent jurisdiction shall
determine that the scope, time or territorial restrictions set forth in any
covenant contained herein are unreasonable, then it is the intention of the
parties that such restrictions be enforced to the fullest extent which the court
deems reasonable, and this Agreement shall thereby be reformed. Each of the
covenants contained in this Agreement shall be construed as an agreement
independent of any other provision in this Agreement, and the existence of any
claim or cause of action of Executive against the Company, whether predicated on
this Agreement or otherwise, shall not constitute a defense to the enforcement
by the Company of such covenants.

        15.   Survival.    The provisions and covenants of Sections 3, 4, 6, 7
and 8 shall survive termination of this Agreement.

        16.   Specific Performance.    Because of the difficulty of measuring
economic losses to the Company as a result of a breach of the covenants
contained in Sections 3, 4, 6, 7 and 8 and because of the immediate and
irreparable damage that could be caused to the Company for which it would have
no other adequate remedy, Executive agrees that the Company shall be entitled to
specific performance and that such covenants may be enforced by the Company in
the event of any breach or threatened breach by Executive, by injunctions,
restraining orders and other appropriate equitable relief. Executive further
agrees to waive any requirement for the securing or posting of any bond in
excess of $50,000 in connection with the obtaining of any such injunctive or any
other equitable relief.

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        17.   Arbitration.    With the exception of Sections 4 and 8, any
unresolved dispute or controversy arising under or in connection with this
Agreement shall be settled exclusively by arbitration, conducted by a single
arbitrator in Houston, Texas, in accordance with the National Rules for the
Resolution of Employment Disputes of the American Arbitration Association
("AAA") then in effect, provided that the parties may agree to use arbitrators
other than those provided by the AAA. The arbitrators shall not have the
authority to add to, detract from, or modify any provision hereof nor to award
punitive damages to any injured party. The arbitrators shall have the authority
to order back pay, severance compensation, reimbursement of costs, including
those incurred to enforce this Agreement, and interest thereon. A decision by
the arbitrator shall be final and binding. Judgment may be entered on the
arbitrator's award in any court having jurisdiction. Responsibility for bearing
the cost of the arbitration shall be determined by the arbitrator and shall be
proportional to the arbitrator's decision on the merits.

        18.   Attorney's Fees.    If any litigation is instituted to enforce or
interpret the provisions of this Agreement or the transactions described herein,
the prevailing party in such action shall be entitled to recover such party's
reasonable attorneys' fees and other costs from the other party hereto.

        19.   Governing Law.    This Agreement shall be governed by and
construed in accordance with the internal laws of the State of Texas.

        20.   Counterparts.    This Agreement may be executed in multiple
counterparts, each of which shall be deemed to be an original and all of which
together shall constitute one and the same instrument.

        IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.

EXECUTIVE:   COMPANY:
 
 
COMFORT SYSTEMS USA, INC.
/s/  THOMAS TANNER      

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Thomas Tanner
 
/s/  WILLIAM MURDY      

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William Murdy
Chief Executive Officer

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Exhibit 10.10

EMPLOYMENT AGREEMENT