Enercept constructs approximately 1,000 homes per year using its pre-engineered panel systems. Since it was founded in 1982, Enercept has become one of the world s leading manufacturers of structural insulated panels, known in the building industry as SIPs. Enercept SIPs are composed of a solid layer of expanded polystyrene insulation laminated between oriented strand board. Studies and performance tests have shown SIPs to be stronger, quieter, safer, faster to construct and 50 percent more energy efficient than traditional methods of construction. Enercept s building systems consist of basement panels, above-grade panels, roof panels and support beams. Enercept maintains a 50,000-square-foot manufacturing plant in Watertown, S.D.