FIRST AMENDMENT AND WAIVER OF FINANCING AGREEMENT

Exhibit 10.6

FIRST AMENDMENT AND WAIVER OF FINANCING AGREEMENT

THIS FIRST AMENDMENT AND WAIVER OF THE FINANCING AGREEMENT, dated as of August 5, 2005 (this “ Amendment and Waiver ”), is by and among each of the lenders that from time to time is a party hereto (such lenders, each individually a “ Lender ” and collectively, the “ Lenders ”), Fortress Credit Corp., as administrative agent for the Lenders (in such capacity, together with its successors and assigns, if any, for the benefit of the Agents and the Lenders in such capacity, the “ Administrative Agent ”), Fortress Credit Corp., as collateral agent (in such capacity, together with its successors and assigns, if any, in such capacity, the “ Collateral Agent ”, and together with the Administrative Agent, each an “ Agent ” and collectively the “ Agents ”) and Modtech Holdings, Inc., a Delaware corporation (the “ Parent ” or “ Borrower ”).

RECITALS:

WHEREAS, the parties hereto are parties to that certain Financing Agreement dated as of February 25, 2005 (the “ Financing Agreement ”);

WHEREAS, the Borrower will issue common stock with in an aggregate purchase price of $11,629,110 to purchasers (the “ Common Stock PIPE ”);

WHEREAS, the Borrower has requested that the Lenders, among other things, (i) waive certain defaults more specifically described herein and (ii) consent to certain amendments to the Second Lien Credit Documents;

WHEREAS, the Borrower has requested that in connection with the above, the Lenders amend and waive certain provisions of the Financing Agreement and the Lenders, subject to the terms and conditions set forth herein, are willing to grant such requests;

NOW, THEREFORE, in consideration of the premises and of the mutual covenants herein contained, the parties hereto agree as follows:

SECTION 1. Defined Terms . Unless otherwise defined herein, all capitalized terms used herein shall have the meanings given them in the Financing Agreement.

SECTION 2. Amendments to the Financing Agreement . The Financing Agreement is, as of the First Amendment Effective Date (as defined below), hereby amended as follows:

1. Section 1.01 of the Financing Agreement (Definitions) is hereby amended by adding the following new definitions thereto in their appropriate alphabetical order:

“ Common Stock PIPE ” shall mean that common stock issued by Borrower to purchasers with in an aggregate purchase price of $11,629,110 to purchasers in accordance with the Purchase Agreement.

“ Common Stock PIPE Transaction Documents ” shall mean the Purchase Agreement and each of the other agreements, documents and instruments providing for or evidencing or relating to the Common Stock PIPE, and any other

agreement, writing, document or instrument executed or delivered at any time in connection with the Common Stock PIPE.

“ First Amendment Effective Date ” shall mean the date on which all of the conditions precedent set forth in Section 4 are satisfied.

“ Second Lien Credit Amendment ” shall mean the Consent, Waiver, Amendment and Exchange Agreement dated as of August 5, 2005, between the Borrower and Amphora Limited, with respect to the Second Lien Credit Agreement and the other Second Lien Loan Documents.

2. Section 1.01 of the Financing Agreement (Definitions) is hereby amended by deleting the definition of “Consolidated EBITDA” in its entirety and replacing it with the following:

“ Consolidated EBITDA ” means, with respect to any Person and its Subsidiaries for any period, the Consolidated Net Income of such Persons for such period, plus (i) without duplication, the sum of the following amounts of such Persons for such period to the extent deducted in determining Consolidated Net Income of such Persons for such period: (A) Consolidated Net Interest Expense, (B) income tax expense, (C) depreciation expense and (D) amortization expense; provided, that for purposes of Sections 7.03(b) and (d) Consolidated EBITDA shall be deemed to be (i) for the period ending June 30, 2005, Consolidated EBITDA for the quarter ending June 30, 2005 multiplied by four (4); (ii) for the period ending September 30, 2005, the sum of (x) Consolidated EBITDA for the quarter ending September 30, 2005 and (y) Consolidated EBITDA for the quarter ending June 30, 2005 multiplied by two (2); (iii) for the period ending December 31, 2005, the sum of (x) Consolidated EBITDA for the quarter ending December 31, 2005 and (y) Consolidated EBITDA for the quarter ending September 30, 2005 and (z) Consolidated EBITDA for the quarter ending June 30, 2005, multiplied by one and one third (1.33) and (iv) for all periods thereafter, Consolidated EBITDA for the 12 month period most recently ended; provided further that for purposes of Section 7.03(a), Consolidated EBITDA shall be deemed to be (i) for the period ending September 30, 2005, Consolidated EBITDA for the quarter ending June 30, 2005 plus the Consolidated EBITDA for the quarter ending September 30, 2005; (ii) for the period ending December 31, 2005, Consolidated EBITDA for the quarter ending June 30, 2005 plus the Consolidated EBITDA for the quarter ending September 30, 2005 plus the Consolidated EBITDA for the quarter ending December 31, 2005 and (iv) for all period thereafter, Consolidated EBITDA for the 12 month period most recently ended.

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3. Section 2.05(c) of the Financing Agreement (Mandatory Prepayments) is hereby amended by adding the following new subsection as follows:

“(vii) Immediately upon the receipt by the Borrower of the proceeds of the Common Stock PIPE, the Borrower shall prepay the outstanding amount of the Term Loan Obligations in an amount equal to $1,150,000.”

4. Section 2.05(d) of the Financing Agreement (Application of Payments) is hereby amended by deleting “and” immediately before “(c)(vi)” and inserting “,” and immediately after “(c)(vi)” inserting “and (c)(vii)”.

5. Section 7.03(a) (Minimum EBITDA) is hereby amended by deleting the information set forth under the heading “Fiscal Quarter Ending” and “Minimum Consolidated EBITDA” in the rows September 30, 2005, December 31, 2005, March 30, 2006, June 30, 2006, September 30, 2006, December 31, 2006, March 31, 2007, June 30, 2007, September 30, 2007 and December 31, 2007 and replacing it with the following:

6. Section 7.03(b) (Senior Secured Leverage Ratio) is hereby amended by deleting the information set forth under the heading “Fiscal Quarter Ending” and “Senior Secured Leverage Ratio” in the rows September 30, 2005, December 31, 2005, March 31, 2006 and June 30, 2006 and replacing it with the following:

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7. Section 7.03)(d) (Consolidated Fixed Charge Coverage Ratio) is hereby amended by deleting the information set forth under the heading “Fiscal Quarter Ending