Abstract: A building structure comprises first and second truss members having cross-members extending therebetween. Each truss member has a generally I-shaped cross-section, of generally constant cross-sectional dimensions, defining elongate longitudinal channels. The longitudinal channels are sized to appropriately receive and retain ends of cross-members extending between the truss members. Supports mounted in the longitudinal channels form receiving pockets which are engaged by the cross-members. A plurality of truss members, formed as parallel arches, may be utilized to form a load-bearing framing structure of a completed building, which may be enclosed by wall coverings such as panelling, siding, plywood or the like. The absence of load-bearing sidewalls permit doors, windows, deck units or the like to be easily introduced into sidewalls.