Spray-on insulation is made of polyurethane foam – the same kind of insulation appliance manufacturers have used in refrigerators and water heaters for years. The liquid polyurethane is pumped through pressurized spray nozzles – as it lands on the surface of your attic or side walls, it expands to form a continuous insulating barrier. The benefits Unlike traditional insulating materials like fiberglass or cellulose, spray foam insulation can seal and fill all the tiny cracks and seams you might not even see. The seamless material virtually eliminates energy-wasting air filtration. In addition, polyurethane has the highest R-value for any given thickness compared to other insulation products. Because it provides a higher R-value per inch, homeowners using foam insulation can use 2×4 construction on exterior walls instead of the 2×6 studs required with traditional insulation. This can save on framing costs, as well as extended window and door jambs. This simple change can also increase the amount of living space by as much as 35 square feet in a 1,500-square-foot home – the equivalent of an extra closet! Foam insulation also helps control moisture condensation, it won’t shrink or settle, and it’s fire- and insect-resistant.