Abstract: A building frame resistant to earthquakes, wind loads, fire, insects and rot includes a peripheral frame wall made of side wall frame modules bolted together along adjacent edges, and end wall modules bolted together along adjacent edges and to the ends of the connected side wall modules. The side wall frame modules are constructed of rectangular steel tubing jig welded together off site at precisely 90.degree. angles so that the assembled building frame is square and true. Diagonal bracing is built into selected side and end wall modules as required for the desired degree of wind resistance. Trusses for supporting a roof on the peripheral wall, also made of rectangular steel tubing, are assembled and welded, and the trusses and wall modules are trucked to the building site.