The pilot stated that he positioned his feet on the toe brake pedals during engine start. After starting, the engine accelerated to a higher rpm than expected, and the airplane began to roll forward. The pilot pressed down with his feet, but the airplane continued to roll. After reducing the throttle to idle, the pilot attempted to steer the airplane with the rudder pedals, but stated that they were fixed and would not move. As the airplane neared a hangar, the pilot shut down the engine with the fuel mixture control and turned the magneto switch off. The airplane then impacted the hangar, resulting in substantial damage to both wings. Postaccident examination by a Federal Aviation Administration inspector revealed no anomalies of the rudder pedal or toe brake systems. The pilot offered that he inadvertently pressed on the torque tube assembly, which was part of the airframe structure located above the toe brake pedals.