By Liz White, UT staffPittsburgh, Pennsylvania-The roof of the Louisiana Superdome, which was partially destroyed by Hurricane Katrina in August, has had a temporary fix in the form of a spray-applied polyurethane roofing system from BaySystems North America.Contractor Brazos Urethanes, with offices in Texas, Louisiana, Georgia and Florida, applied the repair, with crews starting the work in mid-October."The quickest and most effective way to eliminate leaks and dry-in the roof of the Superdome is to use spray applied polyurethane foam," said Wally Scoggins, president of Brazos Urethanes, in a BaySystems statement, "Once the foam hits the substrate, it's waterproof in 30 seconds," he claimed. Rigid polyurethane foam expands during curing to become a seamless, leak-resistant layer of closed-cell insulating foam and can be used on irregular shapes, said BaySystems. An elastomeric coating applied over the foam adds further protection, the company added. "Our spray foam roofing systems have a proven success rate and will equip the Superdome with a lightweight, durable and water-resistant roof," commented Ridge Stockdale, head of spray roofing at BaySystems North America-a unit of Bayer MaterialScience AG. Reports during the aftermath of Katrina, when thousands sheltered in the Superdome, said the 100 mph hurricane winds tore two large holes, 2.5 to 8 metre long and 4 to 5 feet wide, in the roof, allowing rain in. The wind ripped away some of the thick rubber layer which formed the outermost layer on the roof of the132-m high dome. The current roof construction-rubber sheeting on top of insulating boards, nailed onto a thin PU foam layer-was installed on the 30-year old stadium in 2000, when the original roof was discovered to be in need of substantial repair. "