Abstract: An improved building structure and method of use comprising separately fabricated floor, wall and ceiling structures capable of withstanding shear and seismic forces. The floor and ceiling structures of the present invention generally comprise I-beams having foam panels extending therebetween. The wall structure comprises an elongate track rigidly secured to the foundation structure of the building having a plurality of posts secured thereto. Disposed between the posts are a plurality of interlocking foam wall sections which encapsulate the posts of the wall structure. Attached to the top surfaces of the posts are header beams which serve as a support structure for the ceiling structure.

Abstract: A wall structure comprising a track, a plurality of vertical posts secured to the track at predetermined locations, a plurality of horizontal header beams bridging the posts and secured to the posts, and a plurality of wall sections having a grooved side and tongue side and adapted to receive the track in its bottom side, the header beams in its top side, the wall sections assembled together in a tongue and groove relationship along the wall structure with the posts being encapsulated in the tongue and groove joint to form a monolithic wall structure.