Flat foam/single-ply roofing is dependable
Sprayed polyurethane foam (SPF) has been applied to flat American roofs for nearly half a century. It has proven to be a dependable, affordable, single-ply roofing material. Flat foam/single-ply roofing is made of seamless, flexible material that is easy to maintain. With an R-value of 7.14 per 1-inch thickness, it has high-insulative properties. When applied with a finishing top coat, SPF acts as a waterproof barrier and holds up well in severe weather. Builders use elastomeric caulk to patch penetrations to single-ply foam; this ensures integrity during application. Single ply is a cool-roofing membrane system that should be installed by a qualified contractor.
Elastomeric seals applied to the foam must be capable of expanding and contracting with the SPF during both day and night. At the same time, the seals must be strong enough to withstand climate and load conditions. Ask your contractor or manufacturer about single-ply roofing ratings for vapor retarders and breathers. These elements measure the foam's moisture protection capability, which can be important in both humid climates and deserts with monsoon rains.