A chemical additive formulated into either the A-side or B-side which creates bubbles that are trapped in the polyurethane as it solidifies to form foam cells. The gas produced from the blowing agent contributes to over 97% of the volume of polyurethane foam. The blowing agent can be physical or reactive in nature. The physical blowing agents (for example, liquid fluorocarbon) vaporize with the heat of the polyurethane reaction, where a reactive blowing agent (for example, water) reacts with one of the other chemicals in the formulation to produce a gas during the reaction (for example, water and isocyanate yields carbon dioxide).

SPFA believes that the path to a healthful, safe, high-quality and performing SPF installation travels through the hands of a knowledgeable, trained, experienced, and ideally PCP-certified professional contractor.