Abstract: A stressed-skin building panel including structural strengthening members located alternately adjacent the two opposite skin members of the building panel, each of the structural strengthening members being spaced apart from the opposite skin member by a block of high-density rigid foam material, and the remainder of the space between the skin members being occupied by a foamed-in-place foam insulating material adhering to the skin members and structural strengthening members and providing a significant amount of strength and resistance to compressive stresses. The opposite skin members are spaced apart from one another and held together at the proper spacing during and after construction by a plurality of bridge members which form the only direct connection between the skin members by other than insulating foam material, so that the insulating quality of the panels is maximized.