Prefabricated exterior panels and slab foundation systems are disclosed for use in an integrated simple design procedure for use in low-energy use buildings. The panels include a frame formed from conventional framing methods, an inner layer of sheathing fastened to an outer side of the frame, a layer of insulation adhered to an outer surface of the inner layer of sheathing without using fasteners, and an outer layer of sheathing adhered to an outer surface said layer of insulation without using fasteners. Sets of panels are formed with openings for windows or doors. Jigs are used for constructing the panels including corner panels.