Abstract: A building structure has structural wall panels of metal skin/insulating foam/fibrous cement sheet (or structural plywood) laminate construction secured to a floor assembly by brackets which are bolted to longitudinal bearers and to roof truss frames by brackets to enable loads to be distributed through the wall panels, floor assembly and roof truss frames. The longitudinal bearers are formed of C-section beams secured back-to-back and the joists are secured by tabs extending fro the webs of the bearers.