- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------

                UNITED STATES SECURITIES AND EXCHANGE COMMISSION

                                   FORM 10-Q

<Table>
          
(Mark One)
    [X]      QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
             OF THE SECURITIES EXCHANGE ACT OF 1934



             FOR THE QUARTERLY PERIOD ENDED SEPTEMBER 30, 2001

                                   OR




    [ ]      TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
             OF THE SECURITIES EXCHANGE ACT OF 1934



             FOR THE TRANSITION PERIOD FROM           TO
</Table>

                        COMMISSION FILE NUMBER: 1-13011

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

<Table>
                                            
                   DELAWARE                                      76-0526487
       (State or other jurisdiction of                        (I.R.S. Employer
        incorporation or organization)                      Identification No.)
</Table>

                             777 POST OAK BOULEVARD
                                   SUITE 500
                              HOUSTON, TEXAS 77056
              (Address of Principal Executive Offices) (Zip Code)

       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (713) 830-9600

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes [X]  No [ ]

     The number of shares outstanding of the issuer's common stock, as of
November 9, 2001, was 37,509,579.

- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------


                           COMFORT SYSTEMS USA, INC.

                               INDEX TO FORM 10-Q
                    FOR THE QUARTER ENDED SEPTEMBER 30, 2001

<Table>
<Caption>
                                                              PAGE
                                                              ----
                                                           
PART I -- FINANCIAL INFORMATION
  Item 1 -- Financial Statements
     COMFORT SYSTEMS USA, INC.
       Consolidated Balance Sheets..........................    1
       Consolidated Statements of Operations................    2
       Consolidated Statements of Stockholders' Equity......    3
       Consolidated Statements of Cash Flows................    4
       Condensed Notes to Consolidated Financial
        Statements..........................................    5
  Item 2 -- Management's Discussion and Analysis of
     Financial Condition and Results of Operations..........   12
  Item 3 -- Quantitative and Qualitative Disclosures about
     Market Risk............................................   17

PART II -- OTHER INFORMATION
  Item 1 -- Legal Proceedings...............................   18
  Item 2 -- Recent Sales of Unregistered Securities.........   18
  Item 6 -- Exhibits and Reports on Form 8-K................   18
  Item 9 -- Changes and Disagreements with Accountants on
     Accounting and Financial Disclosure....................   18
  Signature.................................................   19
</Table>

                                        i


                           COMFORT SYSTEMS USA, INC.

                          CONSOLIDATED BALANCE SHEETS
                      (IN THOUSANDS, EXCEPT SHARE AMOUNTS)

<Table>
<Caption>
                                                              DECEMBER 31,   SEPTEMBER 30,
                                                                  2000           2001
                                                              ------------   -------------
                                                                              (UNAUDITED)
                                                                       
                                          ASSETS

CURRENT ASSETS:
  Cash and cash equivalents.................................    $ 16,021       $ 15,135
  Accounts receivable, less allowance of $6,789 and
     $10,296................................................     334,152        341,424
  Other receivables.........................................       5,879          5,421
  Inventories...............................................      19,399         19,670
  Prepaid expenses and other................................      10,568         10,412
  Costs and estimated earnings in excess of billings........      44,078         47,453
  Net assets held for sale..................................       3,197             --
                                                                --------       --------
          Total current assets..............................     433,294        439,515
PROPERTY AND EQUIPMENT, net.................................      40,085         35,466
GOODWILL, less accumulated amortization of $32,904 and
  $41,738...................................................     450,493        441,459
OTHER NONCURRENT ASSETS.....................................       2,538          2,854
                                                                --------       --------
          Total assets......................................    $926,410       $919,294
                                                                ========       ========

                           LIABILITIES AND STOCKHOLDERS' EQUITY

CURRENT LIABILITIES:
  Current maturities of long-term debt......................    $    216       $     93
  Current maturities of notes to affiliates and former
     owners.................................................       8,850          5,826
  Accounts payable..........................................     114,613        116,476
  Accrued compensation and benefits.........................      40,880         43,051
  Billings in excess of costs and estimated earnings........      68,574         81,043
  Income taxes payable......................................          --          3,578
  Other current liabilities.................................      26,942         30,067
                                                                --------       --------
          Total current liabilities.........................     260,075        280,134
LONG-TERM DEBT, NET OF CURRENT MATURITIES...................     224,111        190,355
NOTES TO AFFILIATES AND FORMER OWNERS, NET OF CURRENT
  MATURITIES................................................      41,424         37,634
OTHER LONG-TERM LIABILITIES.................................         561            441
                                                                --------       --------
          Total liabilities.................................     526,171        508,564
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY:
  Preferred stock, $.01 par, 5,000,000 shares authorized,
     none issued and outstanding............................          --             --
  Common stock, $.01 par, 102,969,912 shares authorized,
     39,258,913 shares issued...............................         393            393
  Treasury stock, at cost, 2,002,629 and 1,749,334 shares,
     respectively...........................................     (13,119)       (10,924)
  Additional paid-in capital................................     341,923        340,186
  Retained earnings.........................................      71,042         81,075
                                                                --------       --------
          Total stockholders' equity........................     400,239        410,730
                                                                --------       --------
          Total liabilities and stockholders' equity........    $926,410       $919,294
                                                                ========       ========
</Table>

  The accompanying notes are an integral part of these consolidated financial
                                  statements.
                                        1


                           COMFORT SYSTEMS USA, INC.

                     CONSOLIDATED STATEMENTS OF OPERATIONS
                     (IN THOUSANDS, EXCEPT PER SHARE DATA)
                                  (UNAUDITED)

<Table>
<Caption>
                                                  THREE MONTHS ENDED       NINE MONTHS ENDED
                                                     SEPTEMBER 30,           SEPTEMBER 30,
                                                  -------------------   -----------------------
                                                    2000       2001        2000         2001
                                                  --------   --------   ----------   ----------
                                                                         
REVENUES........................................  $423,922   $408,935   $1,191,458   $1,169,204
COST OF SERVICES................................   352,838    335,797      978,869      963,098
                                                  --------   --------   ----------   ----------
          Gross profit..........................    71,084     73,138      212,589      206,106
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES....    58,021     52,735      169,182      158,230
GOODWILL AMORTIZATION...........................     3,151      3,021        9,483        9,063
RESTRUCTURING CHARGES...........................     9,959         --       10,313          238
                                                  --------   --------   ----------   ----------
          Operating income (loss)...............       (47)    17,382       23,611       38,575
OTHER INCOME (EXPENSE):
  Interest income...............................       105         38          483          108
  Interest expense..............................    (7,122)    (5,171)     (19,900)     (17,878)
  Other.........................................       588        157          678          531
                                                  --------   --------   ----------   ----------
          Other income (expense)................    (6,429)    (4,976)     (18,739)     (17,239)
                                                  --------   --------   ----------   ----------
REDUCTIONS IN NON-OPERATING ASSETS AND
  LIABILITIES, NET..............................        --         --       (5,190)          --
                                                  --------   --------   ----------   ----------
INCOME (LOSS) BEFORE INCOME TAXES...............    (6,476)    12,406         (318)      21,336
INCOME TAX EXPENSE (BENEFIT)....................    (2,787)     6,764          268       11,303
                                                  --------   --------   ----------   ----------
NET INCOME (LOSS)...............................  $ (3,689)  $  5,642   $     (586)  $   10,033
                                                  ========   ========   ==========   ==========
NET INCOME (LOSS) PER SHARE:
  Basic.........................................  $  (0.10)  $   0.15   $    (0.02)  $     0.27
                                                  ========   ========   ==========   ==========
  Diluted.......................................  $  (0.10)  $   0.15   $    (0.02)  $     0.27
                                                  ========   ========   ==========   ==========
SHARES USED IN COMPUTING NET INCOME (LOSS) PER
  SHARE:
  Basic.........................................    37,265     37,468       37,429       37,411
                                                  ========   ========   ==========   ==========
  Diluted.......................................    37,265     37,773       37,429       37,449
                                                  ========   ========   ==========   ==========
</Table>

  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                        2


                           COMFORT SYSTEMS USA, INC.

                CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY
                      (IN THOUSANDS, EXCEPT SHARE AMOUNTS)

<Table>
<Caption>
                                       COMMON STOCK          TREASURY STOCK       ADDITIONAL                  TOTAL
                                    -------------------   ---------------------    PAID-IN     RETAINED   STOCKHOLDERS'
                                      SHARES     AMOUNT     SHARES      AMOUNT     CAPITAL     EARNINGS      EQUITY
                                    ----------   ------   ----------   --------   ----------   --------   -------------
                                                                                     
BALANCE AT DECEMBER 31, 1999......  39,258,913    $393    (1,695,524)  $(11,978)   $342,655    $87,895      $418,965
  Issuance of Common Stock:
    Issuance of Employee Stock
      Purchase Plan shares........          --      --       329,212      2,254        (732)        --         1,522
  Common Stock repurchases........          --      --      (175,513)    (1,224)         --         --        (1,224)
  Shares exchanged in repayment of
    notes receivable..............          --      --      (385,996)    (1,975)         --         --        (1,975)
  Shares received from sale of
    businesses....................          --      --       (74,808)      (196)         --         --          (196)
  Net loss........................          --      --            --         --          --    (16,853)      (16,853)
                                    ----------    ----    ----------   --------    --------    --------     --------
BALANCE AT DECEMBER 31, 2000......  39,258,913     393    (2,002,629)   (13,119)    341,923     71,042       400,239
  Issuance of Common Stock:
      Issuance of Employee Stock
        Purchase Plan shares
        (unaudited)...............          --      --       398,287      2,570      (1,737)        --           833
  Shares received from sale of
    businesses (unaudited)........          --      --      (144,992)      (375)         --         --          (375)
  Net income (unaudited)..........          --      --            --         --          --     10,033        10,033
                                    ----------    ----    ----------   --------    --------    --------     --------
BALANCE AT SEPTEMBER 30, 2001
  (unaudited).....................  39,258,913    $393    (1,749,334)  $(10,924)   $340,186    $81,075      $410,730
                                    ==========    ====    ==========   ========    ========    ========     ========
</Table>

  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                        3


                           COMFORT SYSTEMS USA, INC.

                     CONSOLIDATED STATEMENTS OF CASH FLOWS
                                 (IN THOUSANDS)
                                  (UNAUDITED)

<Table>
<Caption>
                                                                NINE MONTHS ENDED
                                                                  SEPTEMBER 30,
                                                              ---------------------
                                                                2000        2001
                                                              ---------   ---------
                                                                    
CASH FLOWS FROM OPERATING ACTIVITIES:
  Net income (loss).........................................  $    (586)  $  10,033
  Adjustments to reconcile net income (loss) to net cash
     provided by operating activities --
     Restructuring charges..................................     10,313         238
     Depreciation and amortization expense..................     18,413      18,072
     Bad debt expense.......................................      3,864       5,041
     Deferred tax expense...................................        101       1,638
     Gain on sale of property and equipment.................       (636)       (195)
     Reduction in non-operating assets and liabilities,
      net...................................................      5,190          --
     Changes in operating assets and liabilities --
       (Increase) decrease in --
          Receivables, net..................................    (54,815)     (8,246)
          Inventories.......................................        867        (477)
          Prepaid expenses and other current assets.........      1,919      (1,142)
          Costs and estimated earnings in excess of
            billings........................................      6,615      (2,547)
          Other noncurrent assets...........................      1,533        (367)
       Increase (decrease) in --
          Accounts payable and accrued liabilities..........     16,272       8,482
          Billings in excess of costs and estimated
            earnings........................................     15,446      11,803
          Other, net........................................     (1,192)       (555)
                                                              ---------   ---------
            Net cash provided by operating activities.......     23,304      41,778
                                                              ---------   ---------
CASH FLOWS FROM INVESTING ACTIVITIES:
  Purchases of property and equipment.......................    (14,687)     (4,642)
  Proceeds from sales of property and equipment.............      1,477         460
  Proceeds from businesses sold.............................         --         964
                                                              ---------   ---------
            Net cash used in investing activities...........    (13,210)     (3,218)
                                                              ---------   ---------
CASH FLOWS FROM FINANCING ACTIVITIES:
  Payments on long-term debt................................   (235,772)   (186,373)
  Borrowings of long-term debt..............................    229,416     146,094
  Proceeds from issuance of common stock....................      1,522         833
  Repurchases of common stock...............................     (1,224)         --
                                                              ---------   ---------
            Net cash used in financing activities...........     (6,058)    (39,446)
                                                              ---------   ---------
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS........      4,036        (886)
CASH AND CASH EQUIVALENTS, beginning of period..............      3,664      16,021
                                                              ---------   ---------
CASH AND CASH EQUIVALENTS, end of period....................  $   7,700   $  15,135
                                                              =========   =========
</Table>

  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                        4


                           COMFORT SYSTEMS USA, INC.

              CONDENSED NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                               SEPTEMBER 30, 2001
                                  (UNAUDITED)

1. BUSINESS AND ORGANIZATION:

     Comfort Systems USA, Inc., a Delaware corporation ("Comfort Systems" and
collectively with its subsidiaries, the "Company"), is a leading national
provider of comprehensive heating, ventilation and air conditioning ("HVAC")
installation, maintenance, repair and replacement services. The Company operates
primarily in the commercial and industrial HVAC markets, and performs most of
its services within manufacturing plants, office buildings, retail centers,
apartment complexes, and healthcare, education and government facilities. In
addition to standard HVAC services, the Company provides specialized
applications such as process cooling, building automation control systems,
electronic monitoring and process piping. Certain locations also perform related
services such as electrical and plumbing.

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:

  Basis of Presentation

     These interim statements should be read in conjunction with the historical
Consolidated Financial Statements and related notes of Comfort Systems included
in the Annual Report on Form 10-K as filed with the Securities and Exchange
Commission for the year ended December 31, 2000 (the "Form 10-K").

     There were no significant changes in the accounting policies of the Company
during the periods presented. For a description of the significant accounting
policies of the Company, refer to Note 2 of Notes to Consolidated Financial
Statements of Comfort Systems included in the Form 10-K.

     The accompanying unaudited consolidated financial statements were prepared
using generally accepted accounting principles for interim financial information
and the instructions to Form 10-Q and applicable rules of Regulation S-X.
Accordingly, these financial statements do not include all information or
footnotes required by generally accepted accounting principles for complete
financial statements and should be read in conjunction with the Form 10-K. The
Company believes all adjustments necessary for a fair presentation of these
interim statements have been included and are of a normal and recurring nature.
The results of operations for interim periods are not necessarily indicative of
the results for the fiscal year.

     The preparation of financial statements in conformity with generally
accepted accounting principles requires the use of estimates and assumptions by
management in determining the reported amounts of assets and liabilities,
disclosures of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting period. Actual results could differ from those estimates.

  Cash Flow Information

     Cash paid for interest for the nine months ended September 30, 2000 and
2001 was approximately $18.8 million and $16.5 million, respectively. Cash paid
for income taxes for the nine months ended September 30, 2000 and 2001 was
approximately $12.1 million and $6.3 million, respectively.

  Accounting Pronouncements

     In July 2001, the Financial Accounting Standards Board ("FASB") issued
Statement of Financial Accounting Standards ("SFAS") No. 141, "Business
Combinations," and SFAS No. 142, "Goodwill and Other Intangible Assets." SFAS
No. 141 requires that the purchase method of accounting be used for all business
combinations initiated after June 30, 2001. SFAS No. 141 also specifies criteria
for recording intangible assets other than goodwill in connection with business
combinations. SFAS No. 142 requires companies to assess goodwill assets for
impairment each year, and more frequently if circumstances suggest an

                                        5

                           COMFORT SYSTEMS USA, INC.

      CONDENSED NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

impairment may have occurred. SFAS No. 142 also introduces a more stringent
framework for assessing goodwill impairment than the approach required under
existing rules. In addition, SFAS No. 142 discontinues the regular charge, or
amortization, of goodwill assets against income.

     SFAS No. 141 is effective immediately. SFAS No. 142 is effective for the
Company beginning January 1, 2002 and early adoption is not allowed for calendar
year companies. Any impairment loss recognized in accordance with SFAS No. 142
will be shown as the cumulative effect of a change in accounting principle in
the Company's income statement. Under this treatment, the Company's income
statement would show after-tax results of operations both with and without the
cumulative effect of the change in accounting principle recognizing an
impairment.

     The Company is currently reviewing these new accounting standards. Under
existing standards, the Company recognizes a non-cash charge of approximately $3
million per quarter in its income statement to amortize its goodwill assets over
40-year lives. This amortization will be discontinued beginning on January 1,
2002 under the new standards.

     The new requirements for assessing whether these goodwill assets have been
impaired involve market-based information that may change prior to the new
rules' effective date of January 1, 2002, and as noted above, early adoption is
not allowed for the Company. As a result, the Company cannot yet determine
whether it will have to recognize a goodwill impairment when the new rules
become effective. However, based on a preliminary review of the new standards,
and based on currently available information, the Company believes it is likely
that it will have to record a non-cash goodwill impairment charge, and that the
amount of that charge will be significant in relation to the Company's
unamortized goodwill balance, which is expected to be approximately $438 million
at December 31, 2001. If such a charge is necessary, the Company anticipates it
would be recorded in the first quarter of 2002 when the new standards become
effective. As noted above, if an impairment charge is recorded upon transition
to the new standards, it will be reflected as the cumulative effect of a change
in accounting principle.

     The Company has specifically provided for the possibility of a non-cash
goodwill impairment charge in its lending agreements with its banks, and
accordingly expects no impact on its current bank credit facility if recognition
of such an impairment charge becomes necessary.

     In August 2001, the FASB issued SFAS No. 144 "Accounting for the Impairment
or Disposal of Long-Lived Assets." This Statement supercedes SFAS No. 121
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
Be Disposed Of," and the accounting and reporting provisions of APB 30,
"Reporting the Results of Operations -- Reporting the Effects of Disposal of a
Segment of a Business, and Extraordinary, Unusual and Infrequently Occurring
Events and Transactions." The new standard will be effective beginning January
1, 2002, and the Company is currently reviewing and evaluating the effects this
standard will have on the Company's reported financial condition, results of
operations, and accounting policies and practices.

     In June 1998, the FASB issued SFAS No. 133, "Accounting for Derivative
Instruments and Hedging Activities." This standard requires entities to
recognize all derivative instruments (including certain derivative instruments
embedded in other contracts) as assets or liabilities in its balance sheet and
measure them at fair value. The statement requires that changes in the
derivatives' fair value be recognized currently in earnings unless specific
hedge accounting criteria are met. The Company adopted this standard effective
January 1, 2001 and there was no impact as the Company does not currently hold
or trade derivative instruments.

  Reclassifications

     Certain reclassifications have been made in prior period financial
statements to conform to current period presentation.

                                        6

                           COMFORT SYSTEMS USA, INC.

      CONDENSED NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

3.  RESTRUCTURING CHARGES:

     During the first quarter of 2001, the Company recorded restructuring
charges of approximately $0.2 million, primarily related to contractual
severance obligations of two operating presidents in connection with the
Company's significant restructuring program undertaken in the second half of
2000. These restructuring charges are net of a gain of approximately $0.1
million related to management's decision to sell a small operation during the
first quarter of 2001.

     During the three and nine months ended September 30, 2000, the Company
recorded restructuring charges of approximately $10.0 million and $10.3 million,
respectively. During the remainder of fiscal 2000, the Company recorded
restructuring charges of approximately $15.0 million. These charges were
primarily associated with restructuring efforts at certain underperforming
operations and the Company's decision to cease its e-commerce activities at
Outbound Services, a subsidiary of the Company. As announced by the Company in
the third quarter of 2000, management performed an extensive review of its
operations during the second half of 2000. As part of this review, management
decided to cease operating at three locations, sell five operations (including
two smaller satellite operations), and merge two companies into other
operations. The restructuring charges were primarily non-cash and included
goodwill impairments of approximately $11.5 million and the writedown of other
long-lived assets of approximately $8.5 million. The remaining restructuring
items primarily include severance and lease termination costs. These
restructuring actions are substantially complete. During the third quarter of
2001, the Company decided to retain one of the operations that was previously
held for sale and reversed approximately $0.3 million of non-cash charges
related to the anticipated loss on the sale of this operation. This amount was
offset by an additional loss on the sale in late September 2001 of the final
operation that was identified as part of this restructuring program. The losses
associated with the other operations that were sold were consistent with the
amounts recorded as restructuring charges in 2000.

     Severance costs recorded in 2000 and 2001 relate to the termination of 147
employees (all of these employees were terminated as of June 30, 2001) including
certain corporate personnel and the management and employees of certain
underperforming locations, and to the departure of the Company's former chief
executive officer. The following table shows the remaining liabilities
associated with the cash portion of the restructuring charges as of September
30, 2001 (in thousands):

<Table>
<Caption>
                                             BALANCE AT                           BALANCE AT
                                             JANUARY 1,                          SEPTEMBER 30,
                                                2001      ADDITIONS   PAYMENTS       2001
                                             ----------   ---------   --------   -------------
                                                                     
Severance..................................    $1,218       $350      $(1,137)      $  431
Lease termination costs and other..........     2,312         --       (1,152)       1,160
                                               ------       ----      -------       ------
          Total............................    $3,530       $350      $(2,289)      $1,591
                                               ======       ====      =======       ======
</Table>

Aggregated financial information related to the operations addressed by
restructuring is as follows (in thousands):

<Table>
<Caption>
                                                              NINE MONTHS ENDED
                                                                SEPTEMBER 30,
                                                              ------------------
                                                                2000      2001
                                                              --------   -------
                                                                   
Revenues....................................................  $ 41,537   $ 6,337
Operating loss..............................................  $(12,853)  $(2,666)
</Table>

4. REDUCTIONS IN NON-OPERATING ASSETS AND LIABILITIES, NET:

     During the quarter ended June 30, 2000, the Company recorded a non-cash
charge of approximately $5.2 million primarily related to the impairment of
certain non-operating assets, principally notes receivable

                                        7

                           COMFORT SYSTEMS USA, INC.

      CONDENSED NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

from former owners of businesses acquired by the Company. In addition, the
Company recorded an impairment of approximately $0.8 million to its minority
investment in two entities associated with the distribution and implementation
of high-end engineering and design software. The Company also recorded a gain of
approximately $0.6 million on the reduction of its subordinated note payable to
a former owner in connection with the settlement of claims with this former
owner.

5. LONG-TERM DEBT OBLIGATIONS:

     Long-term debt obligations consist of the following (in thousands):

<Table>
<Caption>
                                                              DECEMBER 31,   SEPTEMBER 30,
                                                                  2000           2001
                                                              ------------   -------------
                                                                              (UNAUDITED)
                                                                       
Revolving credit facility...................................    $223,700       $190,000
Notes to affiliates and former owners.......................      50,274         43,460
Other.......................................................         627            448
                                                                --------       --------
          Total debt........................................     274,601        233,908
          Less: current maturities..........................       9,066          5,919
                                                                --------       --------
                                                                $265,535       $227,989
                                                                ========       ========
</Table>

  Revolving Credit Facility

     The Company amended its revolving credit facility (the "Credit Facility" or
the "Facility") provided by Bank One, Texas, N.A. ("Bank One") and other banks
(the "Bank Group") in March 2001. As amended, the Credit Facility provides the
Company with a revolving line of credit of up to the lesser of $270 million or
80% of net accounts receivable. The Facility decreases to the lesser of $250
million or 80% of net accounts receivable as of December 31, 2001, and to the
lesser of $240 million or 80% of net accounts receivable as of June 30, 2002.
Borrowings under the Facility are secured by accounts receivable, inventory,
fixed assets other than real estate, and the shares of capital stock of the
Company's subsidiaries. The Credit Facility expires on January 1, 2003, at which
time all amounts outstanding are due.

     The Company has a choice of two interest rate options under the Facility.
Under one option, the interest rate is determined based on the higher of the
Federal Funds Rate plus 0.5% or Bank One's prime rate. An additional margin of
1% to 2% is then added to the higher of these two rates. Under the other
interest rate option, borrowings bear interest based on designated short-term
Eurodollar rates (which generally approximate London Interbank Offered Rates or
"LIBOR") plus 2.5% to 3.5%. The additional margin for both options depends on
the ratio of the Company's debt to earnings before interest, taxes, depreciation
and amortization ("EBITDA"), as defined. Commitment fees of 0.375% to 0.5% per
annum, also depending on the ratio of debt to EBITDA, are payable on the unused
portion of the Facility.

     The Credit Facility prohibits payment of dividends and the repurchase of
shares by the Company, limits certain non-Bank Group debt, and restricts outlays
of cash by the Company relating to certain investments, capital expenditures,
vehicle leases, acquisitions and subordinate debt. The Credit Facility also
provides for the maintenance of certain levels of shareholder equity and EBITDA,
and for the maintenance of certain ratios of the Company's EBITDA to interest
expense and debt to EBITDA.

     Under the terms of the Credit Facility that were in effect as of June 30
and September 30, 2000, the Company was in violation of certain of the
Facility's financial balance and ratio requirements. The Bank Group waived these
violations. The Facility's current restrictions and financial balance and ratio
requirements generally reflect tighter restrictions, greater specificity and
smaller allowable variances on most financial balances and ratios than is
typical for such agreements due to the Company's weaker results in 2000. The

                                        8

                           COMFORT SYSTEMS USA, INC.

      CONDENSED NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

Facility's current requirements also call for the Company to achieve comparable
or modestly higher levels of quarterly EBITDA in 2002 as compared to the
Company's actual results in the first three quarters of 2001, as well as lower
ratios of debt to EBITDA, beginning in the fourth quarter of 2001, than the
Company has achieved in recent quarters. While management believes its
restructuring efforts and operating strategies along with general market
conditions in the commercial/industrial HVAC and building automation controls
industry will enable the Company to meet the Facility's requirements, there can
be no assurance that the Company will be successful in doing so. Management
intends to seek more flexible terms under its borrowing relationships as its
results and credit market conditions allow.

     As of September 30, 2001, the Company had $190.0 million in borrowings
outstanding under the Credit Facility and had incurred interest expense at an
average rate of approximately 9.2% per annum for the first nine months of 2001.
The Credit Facility's interest rate terms as summarized above are effective as
of March 22, 2001 and currently result in an all-in floating interest rate under
the Facility of approximately 6.1%. As of September 30, 2001, the Company also
had $2.6 million in letters of credit outstanding under the Facility, and unused
borrowing capacity under the Facility of $77.4 million. As of November 9, 2001,
$183.0 million in borrowings and $3.0 million in letters of credit were
outstanding under the Facility, and $84.0 million in unused capacity was
available.

  Notes to Affiliates and Former Owners

     Subordinated notes were issued to former owners of certain purchased
companies as part of the consideration used to acquire their companies. These
notes had an outstanding balance of $43.5 million as of September 30, 2001.
These notes bear interest, payable quarterly, at a weighted average interest
rate of 9.73%. In addition, $0.6 million of these notes are convertible by the
holders into shares of the Company's common stock ("Common Stock") at a weighted
average price of $24.25 per share.

     As a result of the Company's covenant violations in 2000 under the Credit
Facility, the Bank Group required that originally scheduled principal payments
to subordinate debt holders be suspended. This requirement took effect in
October 2000. The holders of the Company's subordinate debt generally must wait
one year from any payment defaults to pursue collection remedies against the
Company. In March 2001, the Company entered into amended agreements with
subordinate debt holders representing $46.3 million in principal, including all
the principal originally scheduled to be paid through 2001. These amended
agreements allow for partial payments against certain originally scheduled
payment amounts, defer remaining principal balances to April 2003, and increase
the interest rate on this debt to 10% per annum, payable quarterly. Under these
amended agreements, $6.6 million of principal has been paid from April 1, 2001
to November 9, 2001. The amended agreements also cured all defaults that arose
from the suspension of principal payments to subordinate debt holders that began
in October 2000. As a result of these amended agreements, the Company's annual
maturities of subordinate debt are now $2.5 million for the remainder of 2001,
$3.6 million in 2002, and $37.4 million in 2003.

  Other Long-Term Obligation Disclosures

     The Company anticipates that available borrowings under its Credit Facility
and cash flow from operations will be sufficient to meet the Company's normal
working capital and capital expenditure needs. As noted above, the Company has
agreed to relatively tight restrictions under the Credit Facility. If the
Company violates any of these restrictions, it will be required to negotiate new
terms with its banks. There can be no assurance that in that event, the Company
will receive satisfactory new terms from its banks, or that if the Company needs
additional financing, that such financing can be secured when needed or on terms
the Company deems acceptable.

                                        9

                           COMFORT SYSTEMS USA, INC.

      CONDENSED NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

6. COMMITMENTS AND CONTINGENCIES:

  Claims and Lawsuits

     The Company is party to litigation in the ordinary course of business.
There are currently no pending legal proceedings that, in management's opinion,
would have a material adverse effect on the Company's operating results or
financial condition. The Company has provided accruals for probable losses and
related legal fees associated with certain of these actions in the accompanying
consolidated financial statements.

  Self-Insurance

     The Company retains the risk for worker's compensation, employer's
liability, auto liability, general liability and employee group health claims
resulting from uninsured deductibles per accident or occurrence. Losses up to
the deductible amounts are accrued based upon the Company's known claims
incurred and an estimate of claims incurred but not reported. The accruals are
based upon known facts and historical trends, and management believes such
accruals to be adequate. A wholly owned insurance company subsidiary reinsures a
portion of the risk associated with surety bonds issued by a third party
insurance company. Because no claims have been made against these financial
instruments in the past, management does not expect these instruments will have
a material effect on the Company's consolidated financial statements.

7. STOCKHOLDERS' EQUITY:

  Treasury Stock

     On October 5, 1999, the Company announced that its Board of Directors had
approved a share repurchase program authorizing the Company to buy up to 4.0
million shares of its Common Stock. During 1999, the Company purchased
approximately 1.8 million shares at a cost of approximately $12.9 million.
During 2000, the Company purchased approximately 0.2 million shares at a cost of
approximately $1.2 million. Under the current terms of the Credit Facility, the
Company is prohibited from purchasing additional shares of its Common Stock.

  Restricted Common Stock

     In March 1997, Notre Capital Ventures II, L.L.C. exchanged 2,742,912 shares
of Common Stock for an equal number of shares of restricted voting common stock
("Restricted Voting Common Stock"). The holders of Restricted Voting Common
Stock are entitled to elect one member of the Company's Board of Directors and
0.55 of one vote for each share on all other matters on which they are entitled
to vote. Holders of Restricted Voting Common Stock are not entitled to vote on
the election of any other directors.

     Each share of Restricted Voting Common Stock will automatically convert to
Common Stock on a share-for-share basis (i) in the event of a disposition of
such share of Restricted Voting Common Stock by the holder thereof (other than a
distribution which is a distribution by a holder to its partners or beneficial
owners, or a transfer to a related party of such holders (as defined in Sections
267, 707, 318 and/or 4946 of the Internal Revenue Code of 1986, as amended)),
(ii) in the event any person acquires beneficial ownership of 15% or more of the
total number of outstanding shares of Common Stock of the Company, or (iii) in
the event any person offers to acquire 15% or more of the total number of
outstanding shares of Common Stock of the Company. After July 1, 1998, the Board
of Directors may elect to convert any remaining shares of Restricted Voting
Common Stock into shares of Common Stock in the event 80% or more of the
originally outstanding shares of Restricted Voting Common Stock have been
previously converted into shares of Common Stock. As of September 30, 2001,
there are 1,283,912 shares of Restricted Voting Common Stock remaining.

                                        10

                           COMFORT SYSTEMS USA, INC.

      CONDENSED NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

  Earnings Per Share

     Basic earnings per share ("EPS") is computed by dividing net income by the
weighted average number of shares of common stock outstanding during the year.
Diluted EPS is computed considering the dilutive effect of stock options and
convertible subordinated notes. Options to purchase 4.0 million shares of Common
Stock at prices ranging from $3.63 to $21.438 per share were outstanding for the
three months and nine months ended September 30, 2001, respectively, but were
not included in the computation of diluted EPS because the options' exercise
prices were greater than the respective average market price of the Common
Stock. Options had an anti-dilutive effect for the three and nine months ended
September 30, 2000 because the Company reported a net loss during these periods,
and therefore, are not included in the diluted EPS calculation. Diluted EPS is
also computed by adjusting both net earnings and shares outstanding as if the
conversion of the convertible subordinated notes occurred on the first day of
the year. The convertible subordinated notes had an anti-dilutive effect during
the three months and nine months ended September 30, 2000 and 2001, and
therefore, are not included in the diluted EPS calculation.

     The following table reconciles the number of shares outstanding with the
number of shares used in computing basic and diluted earnings per share for each
of the periods presented (in thousands):

<Table>
<Caption>
                                                      THREE MONTHS       NINE MONTHS
                                                          ENDED             ENDED
                                                      SEPTEMBER 30,     SEPTEMBER 30,
                                                     ---------------   ---------------
                                                      2000     2001     2000     2001
                                                     ------   ------   ------   ------
                                                                    
Common shares outstanding, end of period...........  37,331   37,510   37,331   37,510
Effect of using weighted average common shares
  outstanding......................................     (66)     (42)      98      (99)
                                                     ------   ------   ------   ------
Shares used in computing earnings per
  share -- basic...................................  37,265   37,468   37,429   37,411
Effect of shares issuable under stock option plans
  based on the treasury stock method...............      --      305       --       38
                                                     ------   ------   ------   ------
Shares used in computing earnings per
  share -- diluted.................................  37,265   37,773   37,429   37,449
                                                     ======   ======   ======   ======
</Table>

                                        11


                           COMFORT SYSTEMS USA, INC.

ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS

INTRODUCTION

     The following discussion should be read in conjunction with the historical
Consolidated Financial Statements of Comfort Systems USA, Inc. ("Comfort
Systems" and collectively with its subsidiaries, the "Company") and related
notes thereto included elsewhere in this Form 10-Q and the Annual Report on Form
10-K as filed with the Securities and Exchange Commission for the year ended
December 31, 2000 (the "Form 10-K"). This discussion contains forward-looking
statements regarding the business and industry of Comfort Systems within the
meaning of the Private Securities Litigation Reform Act of 1995. These
statements are based on the current plans and expectations of the Company and
involve risks and uncertanties that could cause actual future activities and
results of operations to be materially different from those set forth in the
forward-looking statements. Important factors that could cause actual results to
differ include risks set forth in "Factors Which May Affect Future Results,"
included in the Form 10-K.

     The Company is a leading national provider of comprehensive heating,
ventilation and air conditioning ("HVAC") installation, maintenance, repair and
replacement services. The Company operates primarily in the commercial and
industrial HVAC markets, and performs most of its services within manufacturing
plants, office buildings, retail centers, apartment complexes, and healthcare,
education and government facilities. In addition to standard HVAC services, the
Company provides specialized applications such as process cooling, building
automation control systems, electronic monitoring and process piping. Certain
locations also perform related services such as electrical and plumbing.

RESULTS OF OPERATIONS

<Table>
<Caption>
                                                    THREE MONTHS ENDED                        NINE MONTHS ENDED
                                                      SEPTEMBER 30,                             SEPTEMBER 30,
                                           ------------------------------------    ----------------------------------------
                                                 2000                2001                 2000                  2001
                                           ----------------    ----------------    ------------------    ------------------
                                                                            (IN THOUSANDS)
                                                                                              
Revenues.................................  $423,922   100.0%   $408,935   100.0%   $1,191,458   100.0%   $1,169,204   100.0%
Cost of services.........................   352,838    83.2%    335,797    82.1%      978,869    82.2%      963,098    82.4%
                                           --------            --------            ----------            ----------
Gross profit.............................    71,084    16.8%     73,138    17.9%      212,589    17.8%      206,106    17.6%
Selling, general and administrative
  expenses...............................    58,021    13.7%     52,735    12.9%      169,182    14.2%      158,230    13.5%
Goodwill amortization....................     3,151     0.7%      3,021     0.7%        9,483     0.8%        9,063     0.8%
Restructuring charges....................     9,959     2.3%         --      --        10,313     0.9%          238      --
                                           --------            --------            ----------            ----------
Operating income (loss)..................       (47)     --      17,382     4.3%       23,611     2.0%       38,575     3.3%
Other income (expense)...................    (6,429)   (1.5)%    (4,976)   (1.2)%     (18,739)   (1.6)%     (17,239)   (1.5)%
Reductions in non-operating assets and
  liabilities, net.......................        --      --          --      --        (5,190)   (0.4)%          --      --
                                           --------            --------            ----------            ----------
Income (loss) before income taxes........    (6,476)   (1.5)%    12,406     3.0%         (318)     --        21,336     1.8%
Income tax expense (benefit).............    (2,787)              6,764                   268                11,303
                                           --------            --------            ----------            ----------
Net income (loss)........................  $ (3,689)   (0.9)%  $  5,642     1.4%   $     (586)     --    $   10,033     0.9%
                                           ========            ========            ==========            ==========
</Table>

     Revenues -- Revenues decreased $15.0 million, or 3.5%, to $408.9 million
for the third quarter of 2001 and decreased $22.3 million, or 1.9%, to $1.169
billion for the first nine months of 2001, compared to the same periods in 2000.
The 3.5% decline in revenue for the quarter was comprised of a 2.4% decline in
revenue related to operations that were sold or shut down since the third
quarter of last year and a 1.1% decrease in revenues at ongoing operations. The
1.9% decline in revenue for the first nine months of 2001 was comprised of a
2.6% decline in revenue related to operations that were sold or shut down since
the third quarter of last year which was partially offset by 0.7% of internal
growth.

     The Company's internal revenue growth rates are lower than the growth rates
it experienced throughout 2000. This results in part from a general slowing in
economic growth in the U.S. economy. The Company's revenue growth rates are also
consistent with management's decreased emphasis on revenue growth in favor of
improvement in profit margins, operating efficiency, and cash flow. In view of
these factors, the Company may

                                        12


continue to experience modest revenue growth in upcoming periods. There can be
no assurance, however, that this strategy will continue to lead to improved
profit margins in the near term. In addition, if general economic activity in
the U.S. slows significantly from current levels, the Company may realize
further decreases in revenue growth and operating margins.

     Gross Profit -- Gross profit increased $2.1 million, or 2.9%, to $73.1
million for the third quarter of 2001 and decreased $6.5 million, or 3.0%, to
$206.1 million for the first nine months of 2001, compared to the same periods
in 2000. As a percentage of revenues, gross profit increased from 16.8% for the
three months ended September 30, 2000 to 17.9% for the three months ended
September 30, 2001 and decreased from 17.8% for the first nine months of 2000 to
17.6% for the first nine months of 2001.

     The Company's improvement in quarter-over-quarter gross profit percentage
primarily resulted from significantly improved quarter-over-quarter results at
three operations that performed poorly in the third quarter of 2000 due to
execution shortfalls on certain sizeable projects.

     The decline in year-to-date gross profit percentages is due to subpar gross
profit performance from certain operations that are undergoing operational and
management changes. The results of these operations generally improved in the
third quarter as compared to the first half of 2001. The negative effect on
gross profit percentage of these operations was largely offset by the
divestiture of certain operations that performed poorly in 2000 and by the
improvement in one of the Company's larger operations that performed poorly in
2000 due to execution shortfalls on a sizeable project.

     Selling, General and Administrative Expenses ("SG&A") -- SG&A decreased
$5.3 million, or 9.1%, to $52.7 million for the third quarter of 2001 and
decreased $11.0 million, or 6.5%, to $158.2 million for the first nine months of
2001, compared to the same periods in 2000. As a percentage of revenues, SG&A
decreased from 13.7% for the three months ended September 30, 2000 to 12.9% for
the three months ended September 30, 2001, and decreased from 14.2% for the
first nine months of 2000 to 13.5% for the first nine months of 2001. Excluding
divested operations, SG&A decreased $1.9 million, or 3.5%, to $52.2 million for
the third quarter of 2001, and decreased $2.3 million, or 1.5%, to $156.2
million for the first nine months of 2001, as compared to the same periods in
2000. Excluding divested operations, SG&A as a percentage of revenues decreased
from 13.2% for the three months ended September 30, 2000 to 12.8% for the three
months ended September 30, 2001, and decreased from 13.8% for the first nine
months of 2000 to 13.4% for the first nine months of 2001. The decreases in SG&A
primarily related to operations that were sold or shut down as well as a
concerted effort to reduce SG&A throughout the Company.

     Restructuring Charges -- During the first quarter of 2001, the Company
recorded restructuring charges of approximately $0.2 million, primarily related
to contractual severance obligations of two operating presidents in connection
with the Company's significant restructuring program undertaken in the second
half of 2000. These restructuring charges are net of a gain of approximately
$0.1 million related to management's decision to sell a small operation during
the first quarter of 2001.

     During the three and nine months ended September 30, 2000, the Company
recorded restructuring charges of approximately $10.0 million and $10.3 million,
respectively, primarily associated with restructuring efforts at certain
underperforming operations and its decision to cease its e-commerce activities
at Outbound Services, a subsidiary of the Company. As announced by the Company
in the third quarter of 2000, management performed an extensive review of its
operations during the second half of 2000. As part of this review, management
decided to cease operating at three locations, sell five operations (including
two smaller satellite operations), and merge two companies into other
operations. The restructuring charges were primarily non-cash and included
goodwill impairments of approximately $11.5 million and the writedown of other
long-lived assets of approximately $8.5 million. The remaining restructuring
items primarily include severance and lease termination costs. These
restructuring actions are substantially complete. During the third quarter of
2001, the Company decided to retain one of the operations that was previously
held for sale and reversed approximately $0.3 million of non-cash charges
related to the anticipated loss on the sale of this operation. This amount was
offset by an additional loss on the sale in late September 2001 of the final
operation that was identified as part of this restructuring program. The losses
associated with the other operations that were sold were consistent with the
amounts recorded as restructuring charges in 2000.
                                        13


     Reductions in Non-Operating Assets and Liabilities, Net -- During the
quarter ended June 30, 2000, the Company recorded a non-cash charge of
approximately $5.2 million primarily related to the impairment of certain
non-operating assets, principally notes receivable from former owners of
businesses acquired by the Company. In addition, the Company recorded an
impairment of approximately $0.8 million to its minority investment in two
entities associated with the distribution and implementation of high-end
engineering and design software. The Company also recorded a gain of
approximately $0.6 million on the reduction of its subordinated note payable to
a former owner in connection with the settlement of claims with this former
owner.

     Income Tax Expense -- The Company's effective tax rates for the nine months
ended September 30, 2001 and 2000 were 53.0% and (84.3%), respectively. The
Company's provision for income taxes differs from the federal statutory rate
primarily due to state income taxes (net of federal income tax benefit) and the
non-deductibility of the amortization of goodwill attributable to certain
acquisitions.

NEW ACCOUNTING PRONOUNCEMENTS

     In July 2001, the Financial Accounting Standards Board ("FASB") issued
Statement of Financial Accounting Standards ("SFAS") No. 141, "Business
Combinations," and SFAS No. 142, "Goodwill and Other Intangible Assets." SFAS
No. 141 requires that the purchase method of accounting be used for all business
combinations initiated after June 30, 2001. SFAS No. 141 also specifies criteria
for recording intangible assets other than goodwill in connection with business
combinations. SFAS No. 142 requires companies to assess goodwill assets for
impairment each year, and more frequently if circumstances suggest an impairment
may have occurred. SFAS No. 142 also introduces a more stringent framework for
assessing goodwill impairment than the approach required under existing rules.
In addition, SFAS No. 142 discontinues the regular charge, or amortization, of
goodwill assets against income.

     SFAS No. 141 is effective immediately. SFAS No. 142 is effective for the
Company beginning January 1, 2002 and early adoption is not allowed for calendar
year companies. Any impairment loss recognized in accordance with SFAS No. 142
will be shown as the cumulative effect of a change in accounting principle in
the Company's income statement. Under this treatment, the Company's income
statement would show after-tax results of operations both with and without the
cumulative effect of a change in accounting principle recognizing an impairment.

     The Company is currently reviewing these new accounting standards. Under
existing standards, the Company recognizes a non-cash charge of approximately $3
million per quarter in its income statement to amortize its goodwill assets over
40-year lives. This amortization will be discontinued beginning on January 1,
2002 under the new standards.

     The new requirements for assessing whether these goodwill assets have been
impaired involve market-based information that may change prior to the new
rules' effective date of January 1, 2002, and as noted above, early adoption is
not allowed for the Company. As a result, the Company cannot yet determine
whether it will have to recognize a goodwill impairment when the new rules
become effective. However, based on a preliminary review of the new standards,
and based on currently available information, the Company believes it is likely
that it will have to record a non-cash goodwill impairment charge, and that the
amount of that charge will be significant in relation to the Company's
unamortized goodwill balance, which is expected to be approximately $438 million
at December 31, 2001. If such a charge is necessary, the Company anticipates it
would be recorded in the first quarter of 2002 when the new standards become
effective. As noted above, if an impairment charge is recorded upon transition
to the new standards, it will be reflected as the cumulative effect of a change
in accounting principle.

     The Company has specifically provided for the possibility of a non-cash
goodwill impairment charge in its lending agreements with its banks, and
accordingly expects no impact on its current bank credit facility if recognition
of such an impairment charge becomes necessary.

     In August 2001, the FASB issued SFAS No. 144 "Accounting for the Impairment
or Disposal of Long-Lived Assets." This Statement supercedes SFAS No. 121
"Accounting for the Impairment of Long-Lived

                                        14


Assets and for Long-Lived Assets to Be Disposed Of," and the accounting and
reporting provisions of APB 30, "Reporting the Results of
Operations -- Reporting the Effects of Disposal of a Segment of a Business, and
Extraordinary, Unusual and Infrequently Occurring Events and Transactions." The
new standard will be effective beginning January 1, 2002, and the Company is
currently reviewing and evaluating the effects this standard will have on the
Company's reported financial condition, results of operations, and accounting
policies and practices.

LIQUIDITY AND CAPITAL RESOURCES

     Cash Flow -- Cash provided by operating activities less customary capital
expenditures plus the proceeds from asset sales is generally called free cash
flow and, if positive, represents funds available to invest in significant
operating initiatives, to acquire other companies or to reduce a company's
outstanding debt or equity. If free cash flow is negative, additional debt or
equity is generally required to fund the outflow of cash.

     For the nine months ended September 30, 2001, the Company had free cash
flow of $37.6 million, an increase of $27.5 million as compared to free cash
flow of $10.1 million in the first nine months of 2000. This improvement
primarily resulted from faster billing by the Company for its project work while
modestly improving the average days to collect receivables once billed, as well
as a decrease in net capital expenditures versus the prior year.

     Cash used in financing activities for the nine months ended September 30,
2001 was $39.4 million and was primarily attributable to net payments of
long-term debt of $40.3 million. Net cash used in financing activities for the
nine months ended September 30, 2000 was $6.1 million and was primarily
attributable to net payments of long-term debt primarily used for working
capital and capital expenditures.

     Revolving Credit Facility -- The Company amended its revolving credit
facility (the "Credit Facility" or the "Facility") provided by Bank One, Texas,
N.A. ("Bank One") and other banks (the "Bank Group") in March 2001. As amended,
the Credit Facility provides the Company with a revolving line of credit of up
to the lesser of $270 million or 80% of net accounts receivable. The Facility
decreases to the lesser of $250 million or 80% of net accounts receivable as of
December 31, 2001, and to the lesser of $240 million or 80% of net accounts
receivable as of June 30, 2002. Borrowings under the Facility are secured by
accounts receivable, inventory, fixed assets other than real estate, and the
shares of capital stock of the Company's subsidiaries. The Credit Facility
expires on January 1, 2003, at which time all amounts outstanding are due.

     The Company has a choice of two interest rate options under the Facility.
Under one option, the interest rate is determined based on the higher of the
Federal Funds Rate plus 0.5% or Bank One's prime rate. An additional margin of
1% to 2% is then added to the higher of these two rates. Under the other
interest rate option, borrowings bear interest based on designated short-term
Eurodollar rates (which generally approximate London Interbank Offered Rates or
"LIBOR") plus 2.5% to 3.5%. The additional margin for both options depends on
the ratio of the Company's debt to earnings before interest, taxes, depreciation
and amortization ("EBITDA"), as defined. Commitment fees of 0.375% to 0.5% per
annum, also depending on the ratio of debt to EBITDA, are payable on the unused
portion of the Facility.

     The Credit Facility prohibits payment of dividends and the repurchase of
shares by the Company, limits certain non-Bank Group debt, and restricts outlays
of cash by the Company relating to certain investments, capital expenditures,
vehicle leases, acquisitions and subordinate debt. The Credit Facility also
provides for the maintenance of certain levels of shareholder equity and EBITDA,
and for the maintenance of certain ratios of the Company's EBITDA to interest
expense and debt to EBITDA.

     Under the terms of the Credit Facility that were in effect as of June 30
and September 30, 2000, the Company was in violation of certain of the
Facility's financial balance and ratio requirements. The Bank Group waived these
violations. The Facility's current restrictions and financial balance and ratio
requirements generally reflect tighter restrictions, greater specificity and
smaller allowable variances on most financial balances and ratios than is
typical for such agreements due to the Company's weaker results in 2000. The
Facility's current requirements also call for the Company to achieve comparable
or modestly higher levels of quarterly EBITDA in 2002 as compared to the
Company's actual results in the first three quarters of 2001, as

                                        15


well as lower ratios of debt to EBITDA, beginning in the fourth quarter of 2001,
than the Company has achieved in recent quarters. While management believes its
restructuring efforts and operating strategies along with general market
conditions in the commercial/industrial HVAC and building automation controls
industry will enable the Company to meet the Facility's requirements, there can
be no assurance that the Company will be successful in doing so. Management
intends to seek more flexible terms under its borrowing relationships as its
results and credit market conditions allow.

     As of September 30, 2001, the Company had $190.0 million in borrowings
outstanding under the Credit Facility and had incurred interest expense at an
average rate of approximately 9.2% per annum for the first nine months of 2001.
The Credit Facility's interest rate terms as summarized above are effective as
of March 22, 2001 and currently result in an all-in floating interest rate under
the Facility of approximately 6.1%. As of September 30, 2001, the Company also
had $2.6 million in letters of credit outstanding under the Facility, and unused
borrowing capacity under the Facility of $77.4 million. As of November 9, 2001,
$183.0 million in borrowings and 3.0 million in letters of credit were
outstanding under the Facility, and $84.0 million in unused capacity was
available.

     Notes to Affiliates and Former Owners -- Subordinated notes were issued to
former owners of certain purchased companies as part of the consideration used
to acquire their companies. These notes had an outstanding balance of $43.5
million as of September 30, 2001. These notes bear interest, payable quarterly,
at a weighted average interest rate of 9.73%. In addition, $0.6 million of these
notes are convertible by the holders into shares of the Company's common stock
("Common Stock") at a weighted average price of $24.25 per share.

     As a result of the Company's covenant violations in 2000 under the Credit
Facility, the Bank Group required that originally scheduled principal payments
to subordinate debt holders be suspended. This requirement took effect in
October 2000. The holders of the Company's subordinate debt generally must wait
one year from any payment defaults to pursue collection remedies against the
Company. In March 2001, the Company entered into amended agreements with
subordinate debt holders representing $46.3 million in principal, including all
the principal originally scheduled to be paid through 2001. These amended
agreements allow for partial payments against certain originally scheduled
payment amounts, defer remaining principal balances to April 2003, and increase
the interest rate on this debt to 10% per annum, payable quarterly. Under these
amended agreements, $6.6 million of principal has been paid from April 1, 2001
to November 9, 2001. The amended agreements also cured all defaults that arose
from the suspension of principal payments to subordinate debt holders that began
in October 2000. As a result of these amended agreements, the Company's annual
maturities of subordinate debt are now $2.5 million for the remainder of 2001,
$3.6 million in 2002, and $37.4 million in 2003.

     Outlook -- The Company anticipates that available borrowings under its
Credit Facility and cash flow from operations will be sufficient to meet the
Company's normal working capital and capital expenditure needs. As noted above,
the Company has agreed to relatively tight restrictions under the Credit
Facility. If the Company violates any of these restrictions, it will be required
to negotiate new terms with its banks. There can be no assurance that in that
event, the Company will receive satisfactory new terms from its banks, or that
if the Company needs additional financing, that such financing can be secured
when needed or on terms the Company deems acceptable.

     Treasury Stock -- On October 5, 1999, the Company announced that its Board
of Directors had approved a share repurchase program authorizing the Company to
buy up to 4.0 million shares of its Common Stock. During 1999, the Company
purchased approximately 1.8 million shares at a cost of approximately $12.9
million. During 2000, the Company purchased approximately 0.2 million shares at
a cost of approximately $1.2 million. Under the current terms of the Credit
Facility, the Company is prohibited from purchasing additional shares of its
Common Stock.

SEASONALITY AND CYCLICALITY

     The HVAC industry is subject to seasonal variations. Specifically, the
demand for new installation and replacement is generally lower during the winter
months due to reduced construction activity during inclement
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weather and less use of air conditioning during the colder months. Demand for
HVAC services is generally higher in the second and third calendar quarters due
to increased construction activity and increased use of air conditioning during
the warmer months. Accordingly, the Company expects its revenues and operating
results generally will be lower in the first and fourth calendar quarters.

     Historically, the construction industry has been highly cyclical. As a
result, the Company's volume of business may be adversely affected by declines
in new installation projects in various geographic regions of the United States.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

     The Company is exposed to market risk primarily related to potential
adverse changes in interest rates. Management is actively involved in monitoring
exposure to market risk and continues to develop and utilize appropriate risk
management techniques.

                                        17


                           COMFORT SYSTEMS USA, INC.

                          PART II -- OTHER INFORMATION

ITEM 1.  LEGAL PROCEEDINGS

     The Company is subject to certain claims and lawsuits arising in the normal
course of business and maintains various insurance coverages to minimize
financial risk associated with these claims. The Company has provided accruals
for probable losses and related legal fees associated with certain of these
actions in its consolidated financial statements. In the opinion of management,
uninsured losses, if any, resulting from the ultimate resolution of these
matters will not have a material adverse effect on the Company's financial
position or results of operations.

ITEM 2.  RECENT SALES OF UNREGISTERED SECURITIES

     During the three month period ended September 30, 2001, the Company did not
issue any unregistered shares of its common stock.

ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

     (a) Exhibits

     None.

     (b) Reports on Form 8-K

     None.

ITEM 9.  CHANGES AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL
DISCLOSURE

     None.

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                                   SIGNATURE

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                          COMFORT SYSTEMS USA, INC.

                                          By:  /s/ J. GORDON BEITTENMILLER
                                            ------------------------------------
                                                  J. Gordon Beittenmiller
                                                 Executive Vice President,
                                            Chief Financial Officer and Director

Dated: November 13, 2001

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