Patent ID: 7493738

Claim:
A modular panel comprising: a cementitious plate; and a stiffener system provided at an underside of the cementitious plate, and comprising a plurality of elongated, spaced-apart hat-section channels running vertically and horizontally to provide bending support for the cementitious plate in both vertical and horizontal directions, wherein each of the hat-section channels includes a substantially flat base member, side members extending upwardly from opposite sides of the base member, and flanges extending generally laterally outwardly from the side members, respectively, for coupling to the underside of the cementitious plate, without interfering with its shear or stress strength, wherein the cementitious plate includes protrusion edges at distal ends to hide the underside of the stiffener system, and wherein the stiffener grid is made of a metal sheet stamped, casted or assembled from multiple hat-section channels into a single piece in a predetermined shape having multiple hat-section channels disposed on the cementitious plate to enhance stiffness and bending strengths of the modular panel, each of which includes attachment means to attach to another modular panel, via a tougue and groove interlocking connection, and selected openings along the hat-section channels to latch on corresponding hooks or fastening clips on a track system for easy installation.