<PAGE>   1
                                                                Exhibit 10.19(G)

                            BUSINESS LOAN AGREEMENT

<TABLE>
<CAPTION>
<S>            <C>            <C>            <S>            <S>             <S>         <S>          <S>
 Principal     Loan Date       Maturity       Loan No       Call / Call     Account     Officer      Initials
$500,000.00    01-26-2001     05-10-2006     0400706685      016 / 6666     120144        019

      References in the shaded area are for Lender's use only and do not limit the applicability of this
                                   document to any particular loan or item.
               Any item above containing "***" has been omitted due to text length limitations.
</TABLE>

Borrower:  FAFCO, INC.                    Lender:  Butte Community Bank
           435 OTTERSON DRIVE                      CHICO OFFICE
           CHICO, CA 95928                         2041 FOREST AVE
                                                   CHICO, CA 95928

================================================================================

THIS BUSINESS LOAN AGREEMENT DATED JANUARY 26, 2001, IS MADE AND EXECUTED
BETWEEN FAFCO, INC. ("BORROWER") AND BUTTE COMMUNITY BANK ("LENDER") ON THE
FOLLOWING TERMS AND CONDITIONS. BORROWER HAS RECEIVED PRIOR COMMERCIAL LOANS
FROM LENDER OR HAS APPLIED TO LENDER FOR A COMMERCIAL LOAN OR LOANS OR OTHER
FINANCIAL ACCOMMODATIONS, INCLUDING THOSE WHICH MAY BE DESCRIBED ON ANY EXHIBIT
OR SCHEDULE ATTACHED TO THIS AGREEMENT ("LOAN"). BORROWER UNDERSTANDS AND AGREES
THAT: (A) IN GRANTING, RENEWING, OR EXTENDING ANY LOAN, LENDER IS RELYING UPON
BORROWER'S REPRESENTATIONS, WARRANTIES, AND AGREEMENTS AS SET FORTH IN THIS
AGREEMENT, AND (B) ALL SUCH LOANS SHALL BE AND REMAIN SUBJECT TO THE TERMS AND
CONDITIONS OF THIS AGREEMENT.

TERM. This Agreement shall be effective as of January 26, 2001, and shall
continue in full force and effect until such time as all of Borrower's Loans in
favor of Lender have been paid in full, including principal, interest, costs,
expenses, attorneys' fees, and other fees and charges, or until May 10, 2006.

CONDITIONS PRECEDENT TO EACH ADVANCE. Lender's obligation to make the initial
Advance and each subsequent Advance under this Agreement shall be subject to
the fulfillment to Lender's satisfaction of all of the conditions set forth in
this Agreement and in the Related Documents.

    LOAN DOCUMENTS. Borrower shall provide to Lender the following documents for
    the Loan: (1) the Note; (2) Security Agreements granting to Lender security
    interests in the Collateral; (3) financing statements perfecting Lender's
    Security Interests; (4) evidence of insurance as required below; (5)
    together with all such Related Documents as Lender may require for the
    Loan; all in form and substance satisfactory to Lender and Lender's counsel.

    BORROWER'S AUTHORIZATION. Borrower shall have provided in form and
    substance satisfactory to Lender properly certified resolutions, duly
    authorizing the execution and delivery of this Agreement, the Note and the
    Related Documents. In addition, Borrower shall have provided such other
    resolutions, authorizations, documents and instruments as Lender or its
    counsel, may require.

    PAYMENT OF FEES AND EXPENSES. Borrower shall have paid to Lender all fees,
    charges, and other expenses which are then due and payable as specified in
    this Agreement or any Related Document.

    REPRESENTATIONS AND WARRANTIES. The representations and warranties set
    forth in this Agreement, in the Related Documents, and in any document or
    certificate delivered to Lender under this Agreement are true and correct.

    NO EVENT OF DEFAULT. There shall not exist at the time of any Advance a
    condition which would constitute an Event of Default under this Agreement
    or under any Related Document.

REPRESENTATIONS AND WARRANTIES. Borrower represents and warrants to Lender, as
of the date of this Agreement, as of the date of each disbursement of loan
proceeds, as of the date of any renewal, extension or modification of any Loan,
and at all times any Indebtedness exists:

    ORGANIZATION. Borrower is a corporation for profit which is, and at all
    times shall be, duly organized, validly existing, and in good standing under
    and by virtue of the laws of the State of California. Borrower is duly
    authorized to transact business in all other states in which borrower is
    doing business, having obtained all necessary filings, governmental licenses
    and approvals for each state in which Borrower is doing business.
    Specifically, Borrower is, and at all times shall be, duly qualified as a
    foreign corporation in all states in which the failure to so qualify would
    have a material adverse effect on its business or financial condition.
    Borrower has the full power and authority to own its properties and to
    transact the business in which it is presently engaged or presently proposes
    to engage. Borrower maintains an office at 435 OTTERSON DRIVE, CHICO, CA
    95928. Unless Borrower has designated otherwise in writing, the principle
    office is the office at which Borrower keeps its books and records including
    its records concerning the Collateral. Borrower will notify Lender of any
    change in the location of Borrower's principle office. Borrower shall do all
    things necessary to preserve and to keep in full force and effect its
    existence, rights and privileges, and shall comply with all regulations,
    rules, ordinances, statutes, orders and decrees of any governmental or
    quasi-governmental authority or court applicable to Borrower and Borrower's
    business activities.

    ASSUMED BUSINESS NAMES. Borrower has filed or recorded all documents or
    filings required by law relating to all assumed business names used by
    Borrower. Excluding the name of Borrower, the following is a complete list
    of all assumed business names under which Borrower does business: NONE.

    AUTHORIZATION. Borrower's execution, delivery, and performance of this
    Agreement and all the Related Documents have been duly authorized by all
    necessary action by Borrower and do not conflict with, result in a
    violation of, or constitute a default under (1) any provision of Borrower's
    articles of incorporation or organization, or bylaws, or any agreement or
    other instrument binding upon Borrower or (2) any law, governmental
    regulation, court decree, or order applicable to Borrower or to Borrower's
    properties.

    FINANCIAL INFORMATION. Each of Borrower's financial statements supplied to
    Lender truly and completely disclosed Borrower's financial condition as of
    the date of the statement, and there has been no material adverse change in
    Borrower's financial condition subsequent to the date of the most recent
    financial statement supplied to Lender. Borrower has no material contingent
    obligations except as disclosed in such financial statements.

    LEGAL EFFECT. This Agreement constitutes, and any instrument or agreement
    Borrower is required to give under this Agreement when delivered will
    constitute legal, valid, and binding obligations of Borrower enforceable
    against Borrower in accordance with their respective terms.

    PROPERTIES. Except as contemplated by this Agreement or as previously
    disclosed in Borrower's financial statements or in writing to Lender and as
    accepted by Lender, and except for property tax liens for taxes not
    presently due and payable, Borrower owns and has good title to all of
    Borrower's properties free and clear of all Security Interests, and has not
    executed any security documents or financing statements relating to such
    properties. All of Borrower's properties are titled in Borrower's legal
    name, and Borrower has not used, or filed a financing statement under, any
    other name for at least the last five (5) years.

    HAZARDOUS SUBSTANCES. Except as disclosed to and acknowledged by Lender in
    writing, Borrower represents and warrants that: (1) During the period of
    Borrower's ownership of Borrower's Collateral, there has been no use,
    generation, manufacture, storage, treatment, disposal, release or threatened
    release of any Hazardous Substance by any person on, under, about or from
    any of the Collateral. (2) Borrower has no knowledge of, or reason to
    believe that there has been (a) any breach or violation of any Environmental
    Laws; (b) any use, generation, manufacture, storage, treatment, disposal,
    release or threatened release of any Hazardous Substance on, under, about or
    from the Collateral by any prior owners or occupants of any of the
    Collateral; or (c) any actual or threatened litigation or claims of any kind
    by any person relating to such matters. (3) Neither Borrower nor any tenant,
    contractor, agent or other authorized user of any of the Collateral shall
    use, generate, manufacture, store, treat, dispose of or release any
    Hazardous Substance on, under, about or from any of the Collateral; and any
    such activity shall be conducted in compliance with all applicable federal,
    state, and local laws, regulations, and ordinances, including with
    limitation all Environmental Laws. Borrower authorizes Lender and its agents
    to enter upon the Collateral to make such inspections and tests as Lender
    may deem appropriate to determine compliance of the Collateral with this
    section of the Agreement. Any inspections or tests made by Lender shall be
    at Borrower's expense and for Lender's purposes only and shall not be
    construed to create any responsibility or liability on the part of Lender to
    Borrower or to any other person. The representations and warranties
    contained herein are based on Borrower's due diligence in investigating the
    Collateral for hazardous waste and Hazardous Substances. Borrower hereby:
    (1) releases and waives any future claims against Lender for indemnity or
    contribution in the event Borrower becomes liable for cleanup or other costs
    under any such laws, and (2) agrees to indemnify and hold harmless Lender
    against any and all claims, losses, liabilities, damages, penalties, and
    expenses which Lender may directly or indirectly sustain or suffer resulting
    from a breach of this section of the Agreement or as a consequence of any
    use, generation, manufacture, storage, disposal, release or threatened
    release of a hazardous waste or substance on the Collateral. The provisions
    of this section of the Agreement, including the obligation to indemnify,
    shall survive the payment of the indebtedness an the termination, expiration
    or satisfaction of this Agreement and shall not be affected by Lender's
    acquisition of any interest in any of the Collateral, whether by foreclosure
    or otherwise.

    LITIGATION AND CLAIMS. No litigation, claim, investigation, administrative
    proceeding or similar action (including those for unpaid taxes) against
    Borrower is pending or threatened, and no other event has occurred which
    may materially adversely affect Borrower's financial condition or
    properties, other than litigation, claims, or other events, if any, that
    have been disclosed to and acknowledged by Lender in writing.

    TAXES. To the best of Borrower's knowledge, all of Borrower's tax returns
    and reports that are or were required to be filed, have been filed, and all
    taxes, assessments and other governmental charges have been paid in full,
    except those presently being or to be contested by Borrower in good faith in
    the ordinary course of business and for which adequate reserves have been
    provided.

    LIEN PRIORITY. Unless otherwise previously disclosed to Lender in writing,
    Borrower has not entered into or granted any Security Agreements, or
    permitted the filing or attachment of any Security Interests on or
    affecting any of the Collateral directly or indirectly securing repayment of

<PAGE>   2
                            BUSINESS LOAN AGREEMENT
LOAN NO.: 0400706685              (CONTINUED)                             PAGE 2
================================================================================

        Borrower's Loan and Note, that would be prior or that may in any way be
        superior to Lender's Security Interests and rights in and to such
        Collateral.

        BINDING EFFECT. This Agreement, the Note, all Security Agreements (if
        any), and all Related Documents are binding upon the signers thereof, as
        well as upon their successors, representatives and assigns, and are
        legally enforceable in accordance with their respective terms.

AFFIRMATIVE COVENANTS. Borrower covenants and agrees with Lender that, so long
        as this Agreement remains in effect, Borrower will:

        NOTICES OF CLAIMS AND LITIGATION. Promptly inform Lender in writing of
        (1) all material adverse changes in Borrower's financial condition, and
        (2) all existing and all threatened litigation, claims, investigations,
        administrative proceedings or similar actions affecting Borrower or any
        Guarantor which could materially affect the financial condition of
        Borrower or the financial condition of any Guarantor.

        FINANCIAL RECORDS. Maintain its books and records in accordance with
        GAAP, applied on a consistent basis, and permit Lender to examine and
        audit Borrower's books and records at all reasonable times.

        FINANCIAL STATEMENTS. Furnish Lender with the following:

                ANNUAL STATEMENTS. As soon as available, but in no event later
                than ninety (90) days after the end of each fiscal year,
                Borrower's balance sheet and income statement for the year
                ended, audited by a certified public accountant satisfactory to
                Lender.

                INTERIM STATEMENTS. As soon as available, but in no event later
                than thirty (30) days after the end of each month, Borrower's
                balance sheet and profit and loss statement for the period
                ended, audited by a certified public accountant satisfactory to
                Lender.

                TAX RETURNS. As soon as available, but in no event later than 5
                days after the applicable filing date for the tax reporting
                period ended, Federal and other governmental tax returns,
                prepared by a certified public accountant satisfactory to
                Lender.

                ADDITIONAL REQUIREMENTS. ACCOUNTS RECEIVABLE AND ACCOUNTS
                PAYABLE STATEMENTS DUE WITHIN 20 DAYS OF EACH MONTH.

        All financial reports required to be provided under this Agreement shall
        be prepared in accordance with GAAP, applied on a consistent basis, and
        certified by Borrower as being true and correct.

        ADDITIONAL INFORMATION. Furnish such additional information and
        statements, as Lender may request from time to time.

        FINANCIAL COVENANTS AND RATIOS. Comply with the following covenants and
        ratios:

                WORKING CAPITAL REQUIREMENTS. MAINTAIN WORKING CAPITAL IN EXCESS
                OF $1,000,000.00. Other Working Capital requirements are as
                follows: MAXIMUM RATIO OF TOTAL LIABILITIES TO TANGIBLE NET
                WORTH 1.25 TO 1.00. In addition, Borrower shall comply with the
                following working capital ratio requirements:

                        CURRENT ASSETS TO CURRENT LIABILITIES RATIO. Maintain a
                        ratio of CURRENT ASSETS TO CURRENT LIABILITIES in excess
                        of 1.500 to 1.000.

                        MINIMUM RATIO OF LIQUID ASSETS TO CURRENT LIABILITIES
                        RATIO. Maintain a ratio of MINIMUM RATIO OF LIQUID
                        ASSETS TO CURRENT LIABILITIES in excess of 1.000 to
                        1.000.

                MINIMUM INCOME AND CASH FLOW REQUIREMENTS. Maintain not less
                than the following Minimum Net Income level: 1.00 QUARTERLY.
                Other Cash Flow requirements are as follows: 1.75 TO 1.00.

                TANGIBLE NET WORTH REQUIREMENTS. Maintain a minimum Tangible Net
                Worth of not less than: $3,000,000.00.

                OPERATING RATIO REQUIREMENTS. Borrower shall comply with the
                following operating ratio requirements:

                EXPENSE RATIO REQUIREMENTS. Borrower shall comply with the
                following expense ratio requirements:

                Except as provided above, all computations made to determine
                compliance with the requirements contained in this paragraph
                shall be made in accordance with generally accepted accounting
                principles, applied on a consistent basis, and certified by
                Borrower as being true and correct.

        INSURANCE. Maintain fire and other risk insurance, public liability
        insurance, and such other insurance as Lender may require with respect
        to Borrower's properties and operations, in form, amounts, coverages and
        with insurance companies acceptable to Lender. Borrower, upon request of
        Lender, will deliver to Lender from time to time the policies or
        certificates of insurance in form satisfactory to Lender, including
        stipulations that coverages will not be cancelled or diminished without
        at least ten (10) days prior written notice to Lender. Each insurance
        policy also shall include an endorsement providing that coverage in
        favor of Lender will not be impaired in any way by any act, omission or
        default of Borrower or any other person. In connection with all policies
        covering assets in which Lender holds or is offered a security interest
        for the Loans, Borrower will provide Lender with such lender's loss
        payable or other endorsements as Lender may require.

        INSURANCE REPORTS. Furnish to Lender, upon request of Lender, reports on
        each existing insurance policy showing such information as Lender may
        reasonably request, including without limitation the following: (1) the
        name of the insurer; (2) the risks insured; (3) the amount of the
        policy; (4) the properties insured; (5) the then current property values
        on the basis of which insurance has been obtained, and the manner of
        determining those values; and (6) the expiration date of the policy. In
        addition, upon request of Lender (however, not more often than
        annually), Borrower will have an independent appraiser satisfactory to
        Lender determine, as applicable, the actual cash value or replacement
        cost of any Collateral. The cost of such appraisal shall be paid by
        Borrower.

        OTHER AGREEMENTS. Comply with all terms and conditions of all other
        agreements, whether now or hereafter existing, between Borrower and any
        other party and notify Lender immediately in writing of any default in
        connection with any other such agreements.

        LOAN PROCEEDS. Use all loan proceeds solely for the following specific
        purposes: TEMPORARY WORKING CAPITAL.

        TAXES, CHARGES AND LIENS. Pay and discharge when due all of its
        indebtedness and obligations, including without limitation all
        assessments, taxes, governmental charges, levies and liens, of every
        kind and nature, imposed upon Borrower or its properties, income, or
        profits, prior to the date on which penalties would attach, and all
        lawful claims that, if unpaid, might become a lien or charge upon any of
        Borrower's properties, income, or profits.

        PERFORMANCE. Perform and comply, in a timely manner, with all terms,
        conditions, and provisions set forth in this Agreement, in the Related
        Documents, and in all other instruments and agreements between Borrower
        and Lender. Borrower shall notify Lender immediately in writing of any
        default in connection with any agreement.

        OPERATIONS. Maintain executive and management personnel with
        substantially the same qualifications and experience as the present
        executive and management personnel; provide written notice to Lender of
        any change in executive and management personnel; conduct its business
        affairs in a reasonable and prudent manner.

        ENVIRONMENTAL STUDIES. Promptly conduct and complete, at Borrower's
        expense, all such investigations, studies, samplings and testing as may
        be requested by Lender or any governmental authority relative to any
        substance, or any waste or by-product of any substance defined as toxic
        or a hazardous substance under applicable federal, state, or local law,
        rule, regulation, order or directive, at or affecting any property or
        any facility owned, leased or used by Borrower.

        COMPLIANCE WITH GOVERNMENTAL REQUIREMENTS. Comply with all laws,
        ordinances, and regulations, now or hereafter in effect, of all
        governmental authorities applicable to the conduct of Borrower's
        properties, businesses and operations, and to the use or occupancy of
        the Collateral, including without limitation, the Americans With
        Disabilities Act. Borrower may contest in good faith any such laws,
        ordinance, or regulation and withhold compliance during any proceeding,
        including appropriate appeals, so long as Borrower has notified Lender
        in writing prior to doing so and so long as, in Lender's sole opinion
        Lender's interests in the Collateral are not jeopardized. Lender may
        require Borrower to post adequate security or a surety bond, reasonably
        satisfactory to Lender, to protect Lender's interest.

        INSPECTION. Permit employees or agents of Lender at any reasonable time
        to inspect any and all Collateral for the Loan or Loans and Borrower's
        other properties and to examine or audit Borrower's books, accounts, and
        records and to make copies and memoranda of Borrower's books, accounts,
        and records. If Borrower now or at any time hereafter maintains any
        records (including without limitation computer generated records and
        computer software programs for the generation of such records) in the
        possession of a third party, Borrower, upon request of Lender, shall
        notify such party to permit Lender free access to such records, all at
        Borrower's expense.

        COMPLIANCE CERTIFICATES. Unless waived in writing by Lender, provide
        Lender at least annually, with a certificate executed by Borrower's
        chief financial officer, or other officer or person acceptable to
        Lender, certifying that the representations and warranties set forth in
        this Agreement are true and correct as of the date of the certificate
        and further certifying that, as of the date of the certificate, no Event
        of Default exists under this Agreement.

ENVIRONMENTAL COMPLIANCE AND REPORTS. Borrower shall comply in all respects with
any and all Environmental Laws; not cause or permit to exist, as a result of an
intentional or unintentional action or omission on Borrower's part or on the
part of any third party, on property owned and/or


<PAGE>   3
                            BUSINESS LOAN AGREEMENT
LOAN NO: 0400706685              (CONTINUED)                             PAGE 3
===============================================================================

   occupied by Borrower, any environment activity where damage may result to
   the environment, unless such environmental activity is pursuant to and in
   compliance with the conditions of a permit issued by the appropriate
   federal, state or local governmental authorities; shall furnish to Lender
   promptly and in any event within thirty (30) days after receipt thereof a
   copy of any notice, summons, lien, citation, directive, letter or other
   communication from any governmental agency or instrumentality concerning any
   intentional or unintentional action or omission on Borrower's part in
   connection with any environmental activity whether or not there is damage to
   the environment and/or other natural resources.

   ADDITIONAL ASSURANCES. Make, execute and deliver to Lender such promissory
   notes, mortgages, deeds of trust, security agreements, assignments,
   financing statements, instruments, documents and other agreements as Lender
   or its attorneys may reasonably request to evidence and secure the Loans and
   to perfect all Security Interests.

LENDER'S EXPENDITURES. If any action or proceeding is commenced that would
materially affect Lender's interest in the Collateral or if Borrower fails to
comply with any provision of this Agreement or any Related Documents, including
but not limited to Borrower's failure to discharge or pay when due any amounts
Borrower is required to discharge or pay under this Agreement or any Related
Documents, Lender on Borrower's behalf may (but shall not be obligated to) take
any action that Lender deems appropriate, including but not limited to
discharging or paying all taxes, liens, security interests, encumbrances and
other claims, at any time levied or placed on any Collateral and paying all
costs for insuring, maintaining and preserving any Collateral. All such
expenditures incurred or paid by Lender for such purposes will then bear
interest at the rate charged under the Note from the date incurred or paid by
Lender to the date of repayment by Borrower. All such expenses will become a
part of the Indebtedness and, at Lender's option, will (A) be payable on
demand; (B) be added to the balance of the Note and be apportioned among and be
payable with any installment payments to become due during either (1) the term
of any applicable insurance policy; or (2) the remaining term of the Note; or
(C) be treated as a balloon payment which will be due and payable at the Note's
maturity.

NEGATIVE COVENANTS. Borrower covenants and agrees with Lender that while this
Agreement is in effect, Borrower shall not, without the prior written consent
of Lender:

   CAPITAL EXPENDITURES. Make or contract to make capital expenditures,
   including leasehold improvements, in any fiscal year in excess of
   $100,000.00 or incur liability for rentals of property (including both real
   personal property) in an amount which, together with capital expenditures,
   shall in any fiscal year exceed such sum.

   INDEBTEDNESS AND LIENS. (1) Except for trade debt incurred in the normal
   course of business and indebtedness to Lender contemplated by this
   Agreement, create, incur or assume indebtedness for borrowed money,
   including capital leases, (2) sell, transfer, mortgage, assign, pledge,
   lease, grant a security interest in, or encumber any of Borrower's assets
   (except as allowed as Permitted Liens), or (3) sell with recourse any of
   Borrower's accounts, except to Lender.

   ADDITIONAL FINANCIAL RESTRICTIONS. MAXIMUM ADDITION BORROWING--$100,000.00.

   CONTINUITY OF OPERATIONS. (1) Engage in any business activities
   substantially different than those in which Borrower is presently engaged,
   (2) cease operations, liquidate, merge, transfer, acquire or consolidate
   with any other entity, change its name, dissolve or transfer or sell
   Collateral out of the ordinary course of business, or (3) pay any dividends
   on Borrower's stock (other than dividends payable in its stock), provided,
   however that notwithstanding the foregoing, but only so long as no Event of
   Default has occurred and is continuing or would result from the payment of
   dividends, if Borrower is a "Subchapter S Corporation" (as defined in the
   Internal Revenue Code of 1986, as amended), Borrower may pay cash dividends
   on its stock to its shareholders from time to time in amounts necessary to
   enable the shareholders to pay income taxes and make estimated income tax
   payments to satisfy their liabilities under federal and state law which
   arise solely from their status as Shareholders of a Subchapter S Corporation
   because of their ownership of shares of Borrower's stock, or purchase or
   retire any of Borrower's outstanding shares or alter or amend Borrower's
   capital structure.

   LOANS, ACQUISITIONS AND GUARANTIES. (1) Loan, invest in or advance money or
   assets, (2) purchase, create or acquire any interest in any other enterprise
   or entity, or (3) incur any obligation as surety or guarantor other than in
   the ordinary course of business.

CESSATION OF ADVANCES. If Lender has made any commitment to make any Loan to
Borrower, whether under this Agreement or under any other agreement, Lender
shall have no obligation to make Loan Advances or to disburse Loan proceeds if:
(A) Borrower or any Guarantor is in default under the terms of this Agreement or
any of the Related Documents or any other agreement that Borrower or any
Guarantor has with Lender; (B) Borrower or any Guarantor dies, becomes
incompetent or becomes insolvent, files a petition in bankruptcy or similar
proceedings, or is adjudged a bankrupt; (C) there occurs a material adverse
change in Borrower's financial condition, in the financial condition of any
Guarantor, or in the value of any Collateral securing any Loan; or (D) any
Guarantor seeks, claims or otherwise attempts to limit, modify or revoke such
Guarantor's guaranty of the Loan or any other loan with Lender; or (E) Lender in
good faith deems itself insecure, even though no Event of Default shall have
occurred.

RIGHT OF SETOFF. To the extent permitted by applicable law, Lender reserves a
right of setoff in all Borrower's accounts with Lender (whether checking,
savings, or some other account). This includes all accounts Borrower holds
jointly with someone else and all accounts Borrower may open in the future.
However, this does not include any IRA or Keogh accounts, or any trust accounts
for which setoff would be prohibited by law. Borrower authorizes Lender, to the
extent permitted by applicable law, to charge or setoff all sums owing on the
indebtedness against any and all such accounts.

DEFAULT. Each of the following shall constitute an Event of Default under this
Agreement:

   PAYMENT DEFAULT. Borrower fails to make any payment when due under the Loan.

   OTHER DEFAULTS. Borrower fails to comply with or to perform any other term,
   obligation, covenant or condition contained in this Agreement or in any of
   the Related Documents or to comply with or to perform any term, obligation,
   covenant or condition contained in any other agreement between Lender and
   Borrower.

   FALSE STATEMENTS. Any warranty, representation or statement made or
   furnished to Lender by Borrower or on Borrower's behalf under this
   Agreement, the Note, or the Related Documents is false or misleading in any
   material respect, either now or at the time made or furnished or becomes
   false or misleading at any time thereafter.

   INSOLVENCY. The dissolution or termination of Borrower's existence as a
   going business, the insolvency of Borrower, the appointment of a receiver
   for any part of Borrower's property, any assignment for the benefit of
   creditors, any type of creditor workout, or the commencement of any
   proceeding under any bankruptcy or insolvency laws by or against Borrower.

   DEFECTIVE COLLATERALIZATION. This Agreement or any of the Related Documents
   ceases to be in full force and effect (including failure of any collateral
   document to create a valid and perfected security interest or lien) at any
   time and for any reason.

   CREDITOR OR FORFEITURE PROCEEDINGS. Commencement of foreclosure or forfeiture
   proceedings, whether by judicial proceeding, self-help, repossession or any
   other method, by any creditor of Borrower or by any governmental agency
   against any collateral securing the Loan. This includes a garnishment of any
   of Borrower's accounts, including deposit accounts, with Lender. However,
   this Event of Default shall not apply if there is a good faith dispute by
   Borrower as to the validity or reasonableness of the claim which is the basis
   of the creditor or forfeiture proceeding and if Borrower gives Lender written
   notice of the creditor or forfeiture proceeding and deposits with Lender
   monies or a surety bond for the creditor or forfeiture proceeding, in an
   amount determined by Lender, in its sole discretion, as being an adequate
   reserve or bond for the dispute.

   EVENTS AFFECTING GUARANTOR. Any of the preceding events occurs with respect
   to any Guarantor of any of the indebtedness or any Guarantor dies or becomes
   incompetent, or revokes or disputes the validity of, or liability under, any
   Guaranty of the Indebtedness. In the event of a death, Lender, at its option,
   may, but shall not be required to, permit the Guarantor's estate to assume
   unconditionally the obligations arising under the guaranty in a manner
   satisfactory to Lender, and, in doing so, cure any Event of Default.

   CHANGE IN OWNERSHIP. Any change in ownership of twenty-five percent (25%) or
   more of the common stock of Borrower.

   ADVERSE CHANGE. A material adverse change occurs in Borrower's financial
   condition, or Lender believes the prospect of payment or performance of the
   Loan is impaired.

   INSECURITY. Lender in good faith believes itself insecure.

   RIGHT TO CURE. If any default, other than a default on Indebtedness, is
   curable and if Borrower or Grantor, as the case may be, has not been given a
   notice of a similar default within the preceding twelve (12) months, it may
   be cured (and no Event of Default will have occurred) if Borrower or
   Grantor, as the case may be, after receiving written notice from Lender
   demanding cure of such default: (1) cure the default within fifteen (15)
   days; or (2) if the cure requires more than fifteen (15) days, immediately
   initiate steps which Lender deems in Lender's sole discretion to be
   sufficient to cure the default and thereafter continue and complete all
   reasonable and necessary steps sufficient to produce compliance as soon as
   reasonably practical.

EFFECT OF AN EVENT OF DEFAULT. If any Event of Default shall occur, except
where otherwise provided in this Agreement or the Related Documents, all
commitments and obligations of Lender under this Agreement or the Related
Documents or any other agreement immediately will terminate (including any
obligation to make further Loan Advances or disbursements), and, at Lender's
option, all indebtedness immediately will become due and payable, all without
notice of any kind to Borrower, except that in the case of an Event of Default
of the type described in the "insolvency" subsection above, such acceleration
shall be automatic and not optional. In addition, Lender shall have all the
rights and remedies provided in the Related Documents or available at law, in
equity, or otherwise. Except as may be prohibited by applicable law, all of
Lender's rights and remedies shall be cumulative and may be exercised
singularly or concurrently. Election by Lender to pursue any remedy shall not
exclude pursuit of any other remedy, and an election to make expenditures or to
take action to perform an obligation of Borrower or of any Grantor shall not
affect

<PAGE>   4
                            BUSINESS LOAN AGREEMENT
LOAN NO: 0400706685                (CONTINUED)                           PAGE 4
===============================================================================

Lender's right to declare a default and to exercise its rights and remedies.

DEMAND DEPOSIT ACCOUNTS. THE BORROWER AGREES TO MOVE OR MAINTAIN THEIR GENERAL
OPERATING CHECKING ACCOUNT WITH THE BANK DURING THE LIFE OF THE LOAN.

ADDITIONAL PROVISION. THIS LOAN IS TO BE AN OPTIONAL ADVANCE NOTE ALLOWING FOR
DISBURSEMENT DURING THE FIRST THREE MONTHS. PAYMENTS ARE TO BE INTEREST ONLY
MONTHLY FOR MARCH, APRIL AND MAY. PRINCIPAL AND INTEREST PAYMENTS BASED UPON
THE FULL $500,000.00 ARE TO COMMENCE ON JUNE 10, 2001 AND AMORTIZE THE LOAN FOR
60 MONTHS.

MISCELLANEOUS PROVISIONS. The following miscellaneous provisions are a part of
this Agreement:

     AMENDMENTS. This Agreement, together with any Related Documents,
     constitutes the entire understanding and agreement of the parties as to
     the matters set forth in this Agreement. No alteration of or amendment to
     this Agreement shall be effective unless given in writing and signed by
     the party or parties sought to be charged or bound by the alteration or
     amendment.

     ATTORNEYS' FEES; EXPENSES. Borrower agrees to pay upon demand all of
     Lender's costs and expenses, including Lender's attorneys' fees and
     Lender's legal expenses, incurred in connection with the enforcement of
     this Agreement. Lender may hire or pay someone else to help enforce this
     Agreement, and Borrower shall pay the costs and expenses of such
     enforcement. Costs and expenses include Lender's attorneys' fees and legal
     expenses whether or not there is a lawsuit, including attorneys' fees and
     legal expenses for bankruptcy proceedings (including efforts to modify or
     vacate any automatic stay or injunction), appeals, and any anticipated
     post-judgment collection services. Borrower also shall pay all court costs
     and such additional fees as may be directed by the court.

     CAPTION HEADINGS. Caption headings in this Agreement are for convenience
     purposes only and are not to be used to interpret or define the provisions
     of this Agreement.

     CONSENT TO LOAN PARTICIPATION. Borrower agrees and consents to Lender's
     sale or transfer, whether now or later, of one or more participation
     interests in the Loan to one or more purchasers, whether related or
     unrelated to Lender. Lender may provide, without any limitation
     whatsoever, to any one or more purchasers, or potential purchasers, any
     information or knowledge Lender may have about Borrower or about any other
     matter relating to the Loan, and Borrower hereby waives any rights to
     privacy Borrower may have with respect to such matters. Borrower
     additionally waives any and all notices of sale of participation
     interests, as well as all notices of any repurchase of such participation
     interests. Borrower also agrees that the purchasers of any such
     participation interests will be considered as the absolute owners of such
     interests in the Loan and will have all the rights granted under the
     participation agreement or agreements governing the sale of such
     participation interests. Borrower further waives all rights of offset or
     counterclaim that it may have now or later against Lender or against any
     purchaser of such a participation interest and unconditionally agrees that
     either Lender or such purchaser may enforce Borrower's obligation under
     the Loan irrespective of the failure or insolvency of any holder of any
     interest in the Loan. Borrower further agrees that the purchaser of any
     such participation interests may enforce its interests irrespective of any
     personal claims or defenses that Borrower may have against Lender.

     GOVERNING LAW. THIS AGREEMENT WILL BE GOVERNED BY, CONSTRUED AND ENFORCED
     IN ACCORDANCE WITH FEDERAL LAW AND THE LAWS OF THE STATE OF CALIFORNIA.
     THIS AGREEMENT HAS BEEN ACCEPTED BY LENDER IN THE STATE OF CALIFORNIA.

     CHOICE OF VENUE. If there is a lawsuit, Borrower agrees upon Lender's
     request to submit to the jurisdiction of the courts of BUTTE County, State
     of California.

     NO WAIVER BY LENDER. Lender shall not be deemed to have waived any rights
     under this Agreement unless such waiver is given in writing and signed by
     Lender. No delay or omission on the part of Lender in exercising any right
     shall operate as a waiver of such right or any other right. A waiver by
     Lender of a provision of this Agreement shall not  prejudice or constitute
     a waiver of Lender's right otherwise to demand strict compliance with that
     provision or any other provision of this Agreement. No prior waiver by
     Lender, nor any course of dealing between Lender and Borrower, or between
     Lender and any Grantor, shall constitute a waiver of any of Lender's
     rights or of any of Borrower's or any Grantor's obligations as to any
     future transactions. Whenever the consent of Lender is required under this
     Agreement, the granting of such consent by Lender in any instance shall
     not constitute continuing consent to subsequent instances where such
     consent is required and in all cases such consent may be granted or
     withheld in the sole discretion of Lender.

     NOTICES. Any notice required to be given under this Agreement shall be
     given in writing, and shall be effective when actually delivered, when
     actually received by telefacsimile (unless otherwise required by law), when
     deposited with a nationally recognized overnight courier, or, if mailed,
     when deposited in the United States mail, as first class, certified or
     registered mail postage prepaid, directed to the addresses shown near the
     beginning of this Agreement. Any party may change its address for notices
     under this Agreement by giving formal written notice to the other parties,
     specifying that the purpose of the notice is to change the party's address.
     For notice purposes, Borrower agrees to keep Lender informed at all times
     of Borrower's current address. Unless otherwise provided or required by
     law, if there is more than one Borrower, any notice given by Lender to any
     Borrower is deemed to be notice given to all Borrowers.

     SEVERABILITY. If a court of competent jurisdiction finds any provision of
     this Agreement to be illegal, invalid, or unenforceable as to any
     circumstance, that finding shall not make the offending provision
     illegal, invalid, or unenforceable as to any other circumstance. If
     feasible, the offending provision shall be considered modified so that it
     becomes legal, valid and enforceable. If the offending provision cannot be
     so modified, it shall be considered deleted from this Agreement. Unless
     otherwise required by law, the illegality, invalidity, or unenforceability
     of any provision of this Agreement shall not affect the legality, validity
     or enforceability of any other provision of this Agreement.

     SUBSIDIARIES AND AFFILIATES OF BORROWER. To the extent the context of any
     provisions of this Agreement makes it appropriate, including without
     limitation any representation, warranty or covenant, the word "Borrower"
     as used in this Agreement shall include all of Borrower's subsidiaries and
     affiliates. Notwithstanding the foregoing however, under no circumstances
     shall this Agreement be construed to require Lender to make any Loan or
     other financial accommodation to any of Borrower's subsidiaries or
     affiliates.

     SUCCESSORS AND ASSIGNS. All covenants and agreements contained by or on
     behalf of Borrower shall bind Borrower's successors and assigns and shall
     inure to the benefit of Lender and its successors and assigns. Borrower
     shall not, however, have the right to assign Borrower's rights under this
     Agreement or any interest therein, without the prior written consent of
     Lender.

     SURVIVAL OF REPRESENTATIONS AND WARRANTIES. Borrower understands and agrees
     that in extending Loan Advances, Lender is relying on all representations,
     warranties, and covenants made by Borrower in this Agreement or in any
     certificate or other instrument delivered by Borrower to Lender under this
     Agreement or the Related Documents. Borrower further agrees that regardless
     of any investigation made by Lender, all such representations, warranties
     and covenants will survive the extension of Loan Advances and delivery to
     Lender of the Related Documents, shall be continuing in nature, shall be
     deemed made and redated by Borrower at the time each Loan Advance is made,
     and shall remain in full force and effect until such time as Borrower's
     Indebtedness shall be paid in full, or until this Agreement shall be
     terminated in the manner provided above, whichever is the last to occur.

     TIME IS OF THE ESSENCE. Time is of the essence in the performance of this
     Agreement.

DEFINITIONS. The following capitalized words and terms shall have the following
meanings when used in this Agreement. Unless specifically stated to the
contrary, all references to dollar amounts shall mean amounts in lawful money of
the United States of America. Words and terms used in the singular shall include
the plural, and the plural shall include the singular, as the context may
require. Words and terms not otherwise defined in this Agreement shall have the
meanings attributed to such terms in the Uniform Commercial Code. Accounting
words and terms not otherwise defined in this Agreement shall have the meanings
assigned to them in accordance with generally accepted accounting principles as
in effect on the date of this Agreement:

     ADVANCE: The word "Advance" means a disbursement of Loan funds made, or to
     be made, to Borrower or on Borrower's behalf on a line of credit or
     multiple advance basis under the terms and conditions of this Agreement.

     AGREEMENT. The word "Agreement" means this Business Loan Agreement, as
     this Business Loan Agreement may be amended or modified from time to
     time, together with all exhibits and schedules attached to the Business
     Loan Agreement from time to time.

     BORROWER. The word "Borrower" means FAFCO, INC., and all other persons and
     entities signing the Note in whatever capacity.

     COLLATERAL. The word "Collateral" means all property and assets granted as
     collateral security for a Loan, whether real or personal property, whether
     granted directly or indirectly, whether granted now or in the future, and
     whether granted in the form of a security interest, mortgage, collateral
     mortgage, deed of trust, assignment, pledge, crop pledge, chattel mortgage,
     collateral chattel mortgage, chattel trust, factor's lien, equipment trust,
     conditional sale, trust receipt, lien, charge, lien or title retention
     contract, lease or consignment intended as a security device, or any other
     security or lien interest whatsoever, whether created by law, contract, or
     otherwise.

     ENVIRONMENTAL LAWS. The words "Environmental Laws" means any and all state,
     federal and local statutes, regulations and ordinances relating to the
     protection of human health or the environment, including without limitation
     the Comprehensive Environmental Response, Compensation, and Liability Act
     of 1980, as amended, 42 U.S.C. Section 9601, et seq. ("CERCLA"), the
     Superfund Amendments and Reauthorization Act of 1986, Pub. L. No. 99-499
     ("SARA"), the Hazardous Materials Transportation Act, 49 U.S.C. Section
     1801, et seq., the Resource Conservation and Recovery Act, 42 U.S.C.
     Section 6901, et seq., Chapters 6.5 through 7.7 of Division 20 of the
     California Health and Safety Code, Section 25100, et seq., or other
     applicable state or federal laws, rules, or regulations adopted pursuant
     thereto.

     EVENT OF DEFAULT. The words "Event of Default" mean any of the events of
     default set forth in this Agreement in the default section of this

<PAGE>   5

                            BUSINESS LOAN AGREEMENT
LOAN NO 0400706685                (CONTINUED)                             PAGE 5
================================================================================

     Agreement.

     GAAP. The word "GAAP" means generally accepted accounting principles.

     GRANTOR. The word "Grantor" means each and all of the persons or entities
     granting a Security Interest in any Collateral for the Loan, including
     without limitation all Borrowers granting such a Security Interest.

     GUARANTOR. The word "Guarantor" means any guarantor, surety, or
     accommodation party of any or all of the Loan.

     GUARANTY. The word "Guaranty" means the guaranty from Guarantor to Lender,
     including without limitation a guaranty of all or part of the Note.

     HAZARDOUS SUBSTANCES. The words "Hazardous Substances" mean materials
     that, because of their quantity, concentration or physical, chemical or
     infectious characteristics, may cause or pose a present or potential
     hazard to human health or the environment when improperly used, treated,
     stored, disposed of, generated, manufactured, transported or otherwise
     handled. The words "Hazardous Substances" are used in their very broadest
     sense and include without limitation any and all hazardous or toxic
     substances, materials or waste as defined by or listed under the
     Environmental Laws. The term "Hazardous Substances" also includes, without
     limitation, petroleum and petroleum by-products or any fraction thereof
     and asbestos.

     INDEBTEDNESS. The word "Indebtedness" means the Indebtedness evidenced by
     the Note or Related Documents, including all principal and interest
     together with all other Indebtedness and costs and expenses for which
     Borrower is responsible under this Agreement or under any of the Related
     Documents.

     LENDER. The word "Lender" means Butte Community Bank, its successors and
     assigns.

     LOAN. The word "Loan" means any and all loans and financial accommodations
     from Lender to Borrower whether now or hereafter existing, and however
     evidenced, including without limitation those loans and financial
     accommodations described herein or described on any exhibit or schedule
     attached to this Agreement from time to time.

     NOTE. The word "Note" means the Note executed by Borrower in the principal
     amount of $500,000.00 dated January 26, 2001, together with all renewals
     of, extensions of, modifications of, refinancings of, consolidations of,
     and substitutions for the note or credit agreement.

     PERMITTED LIENS. The words "Permitted Liens" mean (1) liens and security
     interests securing Indebtedness owed by Borrower to Lender; (2) liens for
     taxes, assessments, or similar charges either not yet due or being
     contested in good faith; (3) liens of materialmen, mechanics,
     warehousemen, or carriers, or other like liens arising in the ordinary
     course of business and securing obligations which are not yet delinquent;
     (4) purchase money liens or purchase money security interests upon or in
     any property acquired or held by Borrower in the ordinary course of
     business to secure Indebtedness outstanding on the date of this Agreement
     or permitted to be incurred under the paragraph of this Agreement titled
     "Indebtedness and Liens"; (5) liens and security interests which, as of
     the date of this Agreement, have been disclosed to and approved by the
     Lender in writing; and (6) those liens and security interests which in the
     aggregate constitute an immaterial and insignificant monetary amount with
     respect to the net value of Borrower's assets.

     RELATED DOCUMENTS. The words "Related Documents" mean all promissory
     notes, credit agreements, loan agreements, environmental agreements,
     guaranties, security agreements, mortgages, deeds of trust, security
     deeds, collateral mortgages, and all other instruments, agreements and
     documents, whether now or hereafter existing, executed in connection with
     the Loan.

     SECURITY AGREEMENT. The words "Security Agreement" mean and include
     without limitation any agreements, promises, covenants, arrangements,
     understandings or other agreements, whether created by law, contract, or
     otherwise, evidencing, governing, representing, or creating a Security
     Interest.

     SECURITY INTEREST. The words "Security Interest" mean, without limitation,
     any and all types of collateral security, present and future, whether in
     the form of a lien, charge, encumbrance, mortgage, deed of trust, security
     deed, assignment, pledge, crop pledge, chattel mortgage, collateral
     chattel mortgage, chattel trust, factor's lien, equipment trust,
     conditional sale, trust receipt, lien or title retention contract, lease
     or consignment intended as a security device, or any other security or
     lien interest whatsoever whether created by law, contract, or otherwise.

     TANGIBLE NET WORTH. The words "Tangible Net Worth" mean Borrower's total
     assets excluding all intangible assets (i.e., goodwill, trademarks,
     patents, copyrights, organizational expenses, and similar intangible
     items, but including leaseholds and leasehold improvements) less total
     debt.

BORROWER ACKNOWLEDGES HAVING READ ALL THE PROVISIONS OF THIS BUSINESS LOAN
AGREEMENT AND BORROWER AGREES TO ITS TERMS. THIS BUSINESS LOAN AGREEMENT IS
DATED JANUARY 26, 2001.

BORROWER:

FAFCO, INC.

By:
   ------------------------------------------------
   NANCY I. GARVIN, VICE PRESIDENT OF FINANCE OF
   FAFCO, INC.

LENDER:

BUTTE COMMUNITY BANK

By:
   ------------------------------------------------
   AUTHORIZED SIGNER


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