Abstract: An acoustical panel has a fiberboard which includes a fibrous filler and a base binder, and a nodulated overlay disposed on the fiberboard, wherein the overlay includes nodulated wool and an overlay binder and has a substantially smooth surface. In one embodiment of the present invention, the fibrous filler is mineral wool and the base binder is granular starch. In an another embodiment of the present invention, the nodulated wool is nodulated mineral wool and the overlay binder is cooked pearl cornstarch. A method of making the durable acoustical panel in accordance with the present invention is disclosed. Initially, an aqueous slurry comprising a fibrous filler, a base binder, and water is formed. The aqueous slurry is deposited onto a moving foraminous support wire to form an aqueous felt, thereby creating a continuous process. Thereafter, the aqueous felt is de-watered to form a wet felt.

Abstract: An acoustical panel has a fiberboard which includes a fibrous filler and a base binder, and a nodulated overlay disposed on the fiberboard, wherein the overlay includes nodulated wool and an overlay binder and has a substantially smooth surface. In one embodiment of the present invention, the fibrous filler is mineral wool and the base binder is granular starch. In an another embodiment of the present invention, the nodulated wool is nodulated mineral wool and the overlay binder is cooked pearl cornstarch.

Abstract: An acoustical panel has a fiberboard which includes a fibrous filler and a base binder, and a nodulated overlay disposed on the fiberboard, wherein the overlay includes nodulated wool and an overlay binder and has a substantially smooth surface. In one embodiment of the present invention, the fibrous filler is mineral wool and the base binder is granular starch. In an another embodiment of the present invention, the nodulated wool is nodulated mineral wool and the overlay binder is cooked pearl cornstarch.

Abstract: A window insulation system adapted for use on large metal or wood framed windows such as used in factories, schools, etc., is installed in spaced relation to a window sash on the side thereof facing the interior of a building. The system includes insulation panels which are mounted on and held in spaced relation to the window by a framework which is supported on brackets mounted on window mullions. Additional stabilization of the system may be provided by brackets which are mounted on window muntins. The framework includes horizontally disposed H-shaped runners with vertical spline members mounted thereon, the spline members having double flanges which are adapted to extend between adjacent edges of the insulation panels. Decorative single-flanged splines cover the space between adjacent panel edges on the building interior side thereof, the single flange extending between the panel edges and the double flanges of the double-flanged spline to removably secure the panels on the framework.