There is disclosed in U.S. Pat. No. 3,401,494 (Anderson) a building wall construction of the type referred to above. In this construction, U-shaped metal fasteners or studs (also referred to as furring channels) are provided the legs or flanges of which include serrated edges that permit the fasteners to be pressed into polystyrene foam sheets. Thereafter, nails or pins driven through metal studs are used to secure the studs, and thus the polystyrene sheets, to a concrete wall. The metal studs provide a backing to which panels of gypsum are secured, the gypsum panels being screwed into the metal studs and thus supported thereby.
Although the studs or fasteners of the Anderson patent take several forms, each is relatively expensive to manufacture, at least as compared with the fastener of the present invention. For example, the fasteners must be made of reasonably heavy duty metal in order to maintain the shapes (U-shaped channel or other specialized shapes) contemplated therein and substantially more handling is required than with the fastener of the present invention.
Other patents of possible interest include U.S. Pat. Nos. 1,562,784 (Olsen); 1,328,201 (Rendano); 1,389,866 (Georgeson et al); 3,106,751 (Fish); 3,394,516 (Taylor et al); 3,696,572 (Jureit); and 1,297,611 (Upson).