SCHEDULE 13D
CUSIP No. 12008R 10 7					Page 1 of 1 Page
Exhibit 1
Joint Filing Agreement
The undersigned parties hereby agree to the joint filing of the Statement on Schedule 13D filed herewith, and any amendments hereto, relating to shares of Common Stock, Par Value $0.01 per share of Builders FirstSource, Inc. with the Securities and Exchange Commission pursuant to Rule 13d-1(k).
Date:		February 9, 2010
			Robotti & Company, Incorporated
	/s/ Robert E. Robotti		By:	/s/ Robert E. Robotti
	Robert E. Robotti			Name: Robert E. Robotti
				Title: President and Treasurer
Robotti & Company, LLC			Robotti & Company Advisors, LLC
By:	/s/ Robert E. Robotti		By:	/s/ Robert E. Robotti
	Name: Robert E. Robotti			Name: Robert E. Robotti
	Title: President and Treasurer			Title: President and Treasurer
By:	/s/ Suzanne Robotti			/s/ Kenneth R. Wasiak
	Suzanne Robotti			Kenneth R. Wasiak
Ravenswood Management Company, L.L.C.				Ravenswood Investment Company, L.P.
By:	/s/ Robert E. Robotti		By:	Ravenswood Management Company, L.L.C.
	Name: Robert E. Robotti			Its General Partner
	Title: Managing Member
			By:	/s/ Robert E. Robotti
Ravenswood Investments III, L.P.				Name: Robert E. Robotti
				Title: Managing Member
By:	Ravenswood Management Company, L.L.C.
	Its General Partner
By:	/s/ Robert E. Robotti
	Name: Robert E. Robotti
	Title: Managing Member
			: