Abstract: The method of forming rigid panel assemblies of this invention eliminates the requirement for mechanical fasteners and may be used to bond wall boards to studs, floor joists to wood flooring such as gypboards, fiberboards, plywood or OSB boards and trusses to ceiling panels. A preferred method of this invention includes applying a thin bead of a thoroughly mixed two-component liquid polyurethane foamable resin adhesive on the surface where the components are to be joined. The foamable resin is formulated to provide a long tack time or delay curing until the assembly is complete. Where the bead is applied to the side faces of the support members, the support members may be turned to orient the foam beads opposite the fibrous panel, which is preferably supported on a flat support surface, most preferably a vacuum plate which draws the panel flat.

Abstract: A method of bonding rigid structural support members to a gypsum or fiberboard panel to form a structural building module. The method involves applying a polyurethane adhesive as a liquid by high pressure stream into a space formed at the junction of the support members and the panel. The space is established by providing a plurality of spaced feet on one planar side of the support members. The support members includes either integrally formed feet, which are placed on the panel, or non-integral feet that are inserted between the support members and the panels. The support members may include holes on the surface bonded to the panel in a face to face relationship or on vertical surfaces in close proximity to the panel through which foam may expand and form a mechanical interlock with the support members. The support members may be metal channels or wood members. The structural building module provides an increased strength bonded structure without the use of nails or other fasteners.

Abstract: A structural building module and a method of bonding rigid structural support members to a gypsum or fiberboard panel to form a structural building module. The method involves applying a polyurethane adhesive as a liquid by high pressure stream into a space formed at the juncture of the support members and the panel. The space is established by providing a plurality of spaced feet on one planar side of the support members. The support members include either integrally formed feet, which are placed on the panel, or non-integral feet that are inserted between the support members and the panels. The support members may include holes on the surface bonded to the panel in a face to face relationship or on vertical surfaces in close proximity to the panel through which foam may expand and form a mechanical interlock with the support members. The support members may be metal channels or wood members.

Abstract: A prefabricated structural element and a method of bonding wallboard to structural elements such as trusses for use in construction or prefabrication of ceilings or walls. The method involves applying a resilient polyurethane foamable liquid by a high pressure impingement mixing spray gun onto areas of a clean, dry wallboard substrate which have wood trusses or studs placed upon them. The foam is sprayed on the drywall at the juncture with the wood members on both sides of the wooden members. The resulting bonded structure permits the unit to be used without further nailing or other attachment means. The foam also permits the combined product to present a flat surface regardless of irregularities in the wood trusses.