Abstract: A lumber compensation device including a lever operated pivoting cam engaging the lumber wherein the cam is affixed to an underlying joist. The cam is affixed to the joist by an elongated toothed member and a U shaped clamp which preclude translational motion of the device. Rotational motion applied to the lever engages the cam with the lumber and further lever rotation forces the lumber into desired conformance after which the lumber is nailed in place. The lumber compensation device is operated by a single individual who is enabled in the performance of nailing the lumber while the device hold the lumber in place.