The FLORIDA BUILDING CODE HAS ADOPTED an extensive set of installation guidelines for hip and ridge tiles after a tile industry survey revealed that damage to many roofs during the state's 2004 hurricane season resulted from poor installation.
“A lot of the roofs we surveyed had only hip and ridge tiles missing,” says Rick Olson, technical director for the Chicago-based Tile Roofing Institute, a nonprofit association of concrete and clay tile producers. “Those tiles could bounce off and damage the field tiles on a roof.”
Missing hip and ridge tiles should not compromise a roof's structural integrity, but Olson says those avoidable damages cost the builder money in repairs. “It's always cheaper to do it right in the first place,” he says.
Concrete and clay tiles—the dominant roofing material used in Florida—usually carry warranties of 50 or more years. But hip and ridge pieces, vulnerable areas on a roof that were once considered decorative accessories, haven't been adequately addressed until recent years.
Some roofs surveyed by the institute after the 2004 season did not have enough nails per tile or had incorrect spacing between tiles, Olson says. Others had inadequate mortar contact between the surface and the tiles.
Now the institute is reinforcing its guidelines based on the method of roof tile application—mechanically fastened, mortar-set, or adhesive-set. For example, hip and ridge tiles must be secured to a metal or wood nailer board during mechanical and adhesive-set applications. And only pre-bagged—rather than site-mixed—mortar can be used for mortar-set applications.
Most of these procedures are not new, Olson says, but they are now in a detailed document for installers to follow. Hip and ridge tiles have always been part of the installation manual, he says, but not to the degree of the latest guidelines, he adds.