Spray foam expands so thoroughly that it fills every little space, preventing air movement and yielding better indoor air quality. Polyurethane foam eliminates air leakage. It seals gaps, cracks, and little holes in what is called the building envelope. What is considered a building envelope? A building envelope is everything that separates the internal building from the external environment, including the roof, doors, windows, floors, and walls. Good insulation in [...]