Southwestern High School
The summers are so hot and the sun so bright, the base flashings on the 76,000-square-feet modified bitumen roof on Southwestern High School in El Centro, CA, were beginning to fail. Rather than tearing off the existing roof and replacing it, the Central Union High School District decided to retrofit it.
"This school is a high-end architectural masterpiece," said Ron Chambers, president of Roof Construction, the roofing contractor conducting the roof replacement. "The existing system was only 11 to 12 years old, so we agreed the best solution was to retrofit the system, which caused minimal disturbance."
Johns Manville's Invinsa™ Roof Board served as the separator between the existing cap sheet and the JM PVC-60 membrane. The system complied with California's Title 24 energy efficiency regulation.
Chambers said the job was made easier by using Invinsa as the cover board.
"It is amazing how hard Invinsa is, and yet how easy it is to cut," he said. "You can't break it with your hand. Invinsa corners won't come up or curl, even if it sits on the roof for several days." Chambers also said the lightweight cover board saved labor hours on the job. Because it is one-third the weight of other cover boards available, Invinsa can be easily loaded, moved and set by one person. As a result, Chambers says that using Invinsa helped reduce the crew size from eight to six over a six-week installation.
The crew also liked the fact that Invinsa did not create dust. Not only was it more comfortable for them to work with, but dust did not get between the laps prior to the welding process.
