The pilot stated that he flew over the airport and observed the windsock favoring runway 16 with a 5- to 8-knot crosswind. He made the landing approach with the right wing down, and had good directional control. The airplane was in the flare when it encountered two wind gusts that lifted the airplane, and caused it to land hard twice. Upon the second hard landing, the nose pitched down and the airplane veered to the left, off the runway, across a dirt strip, over a taxi way, and impacted a hanger nose first. The pilot expressed concerns that the pilot's seat may have slid back during the landing. A Federal Aviation (FAA) inspector and an Airframe & Powerplant Mechanic examined the seat and seat rails, and found it in compliance with applicable Airworthiness Directives (AD) and properly functioning. The right wing and fuselage were substantially damaged.