Spray Foam Insulation What is Polyurethane Foam? Spray Polyurethane Foam is an insulation product that is spray-applied in situ at a building site. Two liquid components, MDI(A) and polyol blend(B) are mixed under pressure and sprayed onto a roof or wall cavity. The reacting liquids expand and solidify into a foam matrix creating a seamless … Continue reading What Is Polyurethane Foam?