Abstract: The invention is a prefabricated rigid wall panel assembly constructed of a plurality of C-shaped studs inserted into kerfs in a foam block. The closed ends of the C-shaped studs and the foam block form substantially planar longitudinal edges of the panel assembly capable of abutting an adjacent panel assembly. Optionally, a header and/or footer plate inserted is into a transverse kerf such that the plate overlaps the ends of the studs, and the header and/or footer plate and the foam block form a substantially planar transverse edge of the panel assembly. Adjacent panel assemblies are preferably secured to one another using a clip, the shape of which depends on the angle at which the panel assemblies abut. Each panel assembly may also have a wire chase.