The fabrication, erection, welding, bolting, construction, or repair of structural steel, reinforcing steel, ornamental iron, reinforcing rods and wire mesh, metal buildings, metal framing, metal siding, metal roofing, and sheet metal structures. Includes such structures as metal building frames and steel structures for highway bridges, oil drilling rigs, towers, complete storage facilities, grain elevators, silos, warehouses, tanks, floating roofs and metal covers, canopies, etc. Does not include steel piping except the terminal piping connection to tanks. Includes all painting, coating, and blasting of such structures. Steel erection and installation is a subclassification of Building Construction.