Composite building panel and method of making composite building panel

A prefabricated composite wall panel for the exterior wall of a structure, comprising:

• a single concrete slab having an exterior face configured to be exposed to the ambient exterior of the structure and an interior face configured for the interior of the structure;
• a plurality of spaced apart C-shaped, metal frame members having a web, a first flange continuous with and projecting orthogonally from one end of said web, and a second flange continuous with and projecting orthogonally from a second end of said web, said first flange being fully embedded in said concrete slab, said one end of said web being embedded in said slab and said web projecting from said interior face of said slab, and said second flange being non-embedded in concrete and spaced apart from the interior surface of said concrete slab;
• and
• a metal lathe reinforcing layer mechanically fastened to said first flange of at least one of said frame members and being fully embedded in said concrete slab;
• wherein said concrete slab has a density of 960 to 1360 kg/m3 (60 to 85 pcf) and a strength from 3.45 to 20.07 kPa (500 to 3000 psi) and includes entrained air that lowers the thermal conductivity of the slab and forms a thermal barrier between said metal frame members and the ambient exterior of the structure.