SEE REVERSE FOR CERTAIN DEFINITIONS

Exhibit 4.1

CUSIP ______________

UNITS CONSISTING OF ONE SHARE OF COMMON STOCK AND ONE WARRANT TO PURCHASE ONE SHARE OF

COMMON STOCK

THIS CERTIFIES THAT                                                                                                                   is the owner of                                                                                                                                                                                                  Units.

Each Unit (“Unit”) consists of one (1) share of common stock, par value $.0001 per share (“Common Stock”), of Builder Acquisition Corp., a Delaware corporation (the “Company”), and one warrant (the “Warrants”). Each Warrant entitles the holder to purchase one (1) share of Common Stock for $6.00 per share (subject to adjustment). Each Warrant will become exercisable on the later of (i)            , 2007 or (ii) the Company’s completion of a merger, capital stock exchange, asset acquisition, stock purchase or other business combination transaction of one or more operating businesses in the homebuilding industry that is its initial business combination and which meets the size, timing and other criteria outlined in the Company’s registration statement on Form S-1 initially filed with the Securities and Exchange Commission on July 9, 2006 (File No. 333-134909), as amended, and will expire unless exercised before 5:00 p.m., New York City Time, on                 , 2010, or earlier upon redemption (the “Expiration Date”); provided, however, if such expiration date is in the State of New York is a holiday or a day on which banking institutions are authorized to close, then the Expiration Date shall mean 5:00 p.m., (New York Time), the next following day in which, in the State of New York is not a holiday or a day which banks are authorized to close. The Common Stock and Warrants comprising the Units represented by this certificate are not transferable separately prior to                 , 2006, subject to earlier separation in the discretion of JMP Securities. The terms of the Warrants are governed by a Warrant Agreement, dated as of                 , 2006, between the Company and Continental Stock Transfer & Trust Company, as Warrant Agent, and are subject to the terms and provisions contained therein, all of which terms and provisions the holder of this certificate consents to by acceptance hereof. Copies of the Warrant Agreement are on file at the office of the Warrant Agent at 17 Battery Place, New York, New York 10004, and are available to any Warrant holder on written request and without cost.

This certificate is not valid unless countersigned by the Transfer Agent and Registrar of the Company.

Witness the facsimile seal of the Company and the facsimile signature of its duly authorized officers.

BUILDER ACQUISITION CORP.

The Company will furnish without charge to each stockholder who so requests, a statement of the powers, designations, preferences and relative, participating, optional or other special rights of each class of stock or series thereof of the Company and the qualifications, limitations, or restrictions of such preferences and/or rights.

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations:

Additional Abbreviations may also be used though not in the above list.

For value received,                                                               hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER

IDENTIFYING NUMBER OF ASSIGNEE

(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

Units

represented by the within Certificate, and do hereby irrevocably constitute and appoint                                                                                                                                                                                                          Attorney to transfer the said Units on the books of the within named Company will full power of substitution in the premises.

Dated                         

Signature(s) Guaranteed: