Spray Foam Roofing Adhesive for Commercial Roofing Systems | SprayFoam Magazine Content

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Spray Foam Roofing Adhesive for Commercial Roofs

Spray foam is becoming ever popular as a roofing adhesive to secure EDPM membranes directly to commercial roof decks for a totally non-penetrating, fastener-free roofing system. These adhesives are also commonly used as a composite system to adhere foam board insulation to roof decks. Once the insulation board has been fully adhered, the adhesive is spray applied again over top of the foam board, to fasten the EDPM membrane. This creates a totally insulated and sealed roofing system.

Application

Foam roofing adhesive systems are applied much like an ordinary spray foam roof installation. When the foam adhesive has sufficiently cured to develop a tacky skin, the EDPM membrane is then laid onto the surface and rolled with a weighted roller to ensure proper adhesion. Usually within 15 to 25 minutes, as the foam adhesive continues to cure, a secure bond is formed between the substrate and the membrane or foam insulation board.

R-Value

Each layer of foam roofing adhesive is typically 1/16 to 1/8-inch thick and can provide redundant waterproofing characteristics to the roofing assembly, as well as some added R-value. Also, thermal bridging that would be otherwise attributed to mechanical fasteners is eliminated. The National Roofing Contractors Association (NRCA) estimates a 3-8% loss in R-value when mechanical fasteners are used. Foam roofing adhesives also help seal insulation board joints, which cause losses of up to 10% of the R-value.

Wind Uplift Mitigation

Foam roofing adhesive systems are closed-cell SPF formulations that enhance the structural integrity of the roof deck. These systems can boast superior wind-uplift resistance, delivered with code-rated assemblies ranging from FM 1-90 up to FM 1-990 to UL 580 and UL 1897 approvals. As a result of this exceptional wind uplift performance, these systems commonly offer substantially higher wind uplift resistance than typical systems.

Minimal Disruption to Building Occupants

The foam roofing adhesive application process is quicker and quieter than that of mechanically fastened systems, making it an ideal solution for reroofing occupied buildings. The spray application process can significantly reduce labor costs and operational interruptions.