Foam roofs (Sprayed Polyurethane Foam – SPF) have been controversial for years, and haven’t always proved to be a successful solution for building owners. However, SPF does have it’s place within the Roofing Industry for certain types of buildings and certain applications. See the following:
The Pro’s for Foam Roofing:
- Seamless: when applied they create a single-monolithic membrane. Therefore there are no seams that may come apart and leak.
- Flexible: The foam can be sprayed onto virtually any surface, and sprayed around irregular protrusions.
- Lightweight: Foam typically weighs around 50 lbs. per 100 square feet (per square), versus 800 lbs. per square for a built-up rock roof, or a 100 lbs for a single-ply membrane roof system.
- Thermal Insulation: SPF has the best insulation properties available for commercial construction today. The R-Value is approximately 7.14 per inch thickness.
- Waterproofing debate: Foam manufactures maintain that because foam has billions of closed cells it acts as an air barrier, preventing moisture infiltration into a building. The debate begins when moisture penetrates all the way to the substrate and what occurs then. If the intrusion is caught in time, and a proper repair is made, then little damage can occur, otherwise unchecked there is a problem.
The Cons of Foam Roofing:
- Double Material Application: The 2-part application process is so critical when spraying both foam and coating, any lack of attentiveness to detail skews the entire roof system. Evenness is challenging across a wide space without creating ponding areas. The same also goes for the top-coating that’s applied after the foam is sprayed. Also, wind can be an issue. Repainting cars can be expensive.
- On Going Maintenance: A foam system has to be maintained carefully. Susceptible to punctures and tears. If the coating is compromised the foam will soak up moisture like a sponge and then the problems begin. Blistering occurs from the moisture that’s trapped, expanding the foam, and it also allows for dry rot to occur if the moisture reaches the substrate. Foam roofs have to be re-coated every 7-10 years.
- Durability Issues: Vendor abuse occurs more frequently with foam roofs than other types of systems. It’s imperative that a customer keep track of who’s on their roof and if any damages have occurred. This is one of the biggest reasons some foam roofs have failed; it’s not because of the foam itself, but rather from the building owner not knowing the roof system has been compromised as time has passed, and moisture intrusion has occurred again and again to the point of serious deterioration.
- Mechanical Service Nightmares: How does buried electrical conduit, gas lines, and AC ducts get serviced or replaced without compromising the integrity of the roof?
- Foam Roofs Are For The Birds: Birds, for what ever reason, peck holes into the foam roof and leave it compromised. Some foam material suppliers have added chemicals to their formulations to detract the birds from penetrating the top surface, however the jury is still out on the effects of this solution.
- Risk – Reward Ratio: For some building owners, despite a lower initial cost, the addition of re-coating costs, along with repair costs, pushes the Life Cycle Costs for a Foam Roof past the True Cost criteria for some companies.
Bottom line; the numbers often times don’t pencil out for a Foam Roof.
Let SBR Inc., a Roofing and Waterproofing company in Burbank, California, help you sort out the best solution for roof replacement for your building. Contact SBR today. 888-766-3748