Pilot’s Improper Installation Of The Control Stick Pushrod Assemblies, Which Resulted In Separation Of The Left Pushrod And A Total Loss Of Roll Control Analysis: While returning to the airport from a routine pleasure flight, the pilot of the experimental lightsport airplane reported a total flight control failure while maneuvering to land. Data from the onboard electronic flight instrument system and witness statements indicated that after turning from the crosswind to the downwind leg, the airplane entered an uncontrolled descending left turn consistent with a spin or spiral, culminating in a collision with a warehouse roof about 0.75 mile from the runway threshold.