The Spray Polyurethane Foam (SPF) Roofing Insulation System is a great way to provide high-grade roof insulation for superior protection from the elements. With an insulation value of R-6.3 per inch of thickness, SPF effectively controls air infiltration, and reduces cooling and heating costs. During the restoration process, the entire roof is insulated with SPF (at a minimum thickness of one inch) and sealed with a reflective finish coat.