Abstract: A composition and a method for producing primarily water blown polyurethane foams is provided. The composition uses isocyanate ratios greater than conventional foam system to provide a water blown polyurethane foam suitable for a wide variety of applications including spray roofing, insulation, etc. The preferred composition for preparing a polyurethane foam comprises an isocyanate component and a polyol component, wherein the polyol component preferably comprises a combination of Mannich polyol, polyester polyol, and polyether polyol. Preferably, the composition includes water to act as a blowing agent and a metal salt catalyst to assist in the reaction. Preferably, the isocyanate index is between about 1.2 and about 2.0. Additional catalysts, surfactants, flame retardants, and blowing agents may also be used depending upon the desired finished product.