Dave Gelsi is a senior roofing designer with over 35 years of experience. Cayuga County sought assistance from the 104-year-old architectural firm Beardsley Design Associates when they began to experience leaks and resulting interior damage in the County Office Building in Auburn, NY.
The existing 13,384-square-foot roof with a 109-foot elevation was a 15-year-old EPDM system, mechanically fastened into the concrete deck. The building, a high-profile local landmark, housed the chambers of the county legislators. Gelsi specified low-rise foam for attaching the insulation and an adhered, heat-welded Sarnafil PVC membrane for the re-roofing project.
“I decided on the low-rise foam for several reasons,” he says. “First of all, it was a concrete deck that wouldn’t withstand the hammering and pounding and drilling of mechanical fasteners.
Secondly, at six stories high, it would be very hard to feed any other type of adhesive system, such as hot asphalt, to the roof. And finally, it was occupied, so we had to be fairly quiet and careful during the installation. Plus, the foam is very adhesive-minded – it sticks to anything and everything.”
Andy Sheridan and Apple Roofing of Syracuse, NY, had been involved in the project preliminaries, performing test cuts and providing preliminary pricing. When the bids for the work were collected from several contractors, Apple got the nod.
“They were successful on several of our other projects over the years,” says Gelsi. “This job went very smoothly without any problems. They were on schedule and they did a nice job. The roof is performing very well and we haven’t had any reports of problems at all.”
Polyurethane Insulating Adhesive (PIA), also known as low-rise foam or foam adhesive, has seen a marked increase in use in recent years. More and more roofing specifications are calling for the fully adhered PIA approach over mechanical fasteners. Contractors who can install a quality roof system using low-rise foam are finding they have a distinct business advantage.
Like its “big brother” SPF, Polyurethane Insulating Adhesive is spray applied to the substrate. Also like SPF, it is manufactured on-site, but engineered on the molecular level to perform a specific task.
BASF Polyurethane Insulating Adhesive is water-blown and low-viscosity, available in formulations for both hot and cold environments, sets in five to 10 minutes, and has passed FM Global wind uplift tests with several substrates.
Another performance advantage offered by polyurethane foam adhesive is the elimination of thermal bridging. Whereas mechanical fasteners often add to this problem, the seamless, monolithic application of polyurethane foam adhesive actually helps provide more insulation for the roof system, as well as helping to infill the spaces between the insulation boards.
“Incorporating the low rise foam into our roofing mix has absolutely helped our business,” says Sheridan, estimator and project manager for Apple Roofing. “It helps us bid on and win more jobs, and it helps us to get them done quickly and more efficiently.”