Codes
In order for a concrete roof tile to conform to building codes, it must be manufactured to ASTM C-1492 and ICC AC 180 test standards. These standards address material characteristics and physical properties such as strength, water absorption, permeability, freeze/ thaw resistance and dimensional consistency. The International Building Code and International Residential Code contain provisions for tile roof installation, in Section 1507.3.8 and section R905.3.7, respectively. The Florida Building Code, among the strictest in the country, sets forth stringent requirements for the way tile roofs are to be fastened (Section 1609) in high-wind regions.

Regional Variations
According to the Tile Roof Institute, many homeowners living in areas of heavy snowfall mistakenly believe that snow accumulation on a tile roof is dangerous and arrange for snow removal which, in most cases, is not only unnecessary, but also dangerous and potentially damaging to the roof tiles. Snow is an effective insulator, and snow guards positioned across a roof's surface can confine snow safely on roofs until the spring melt.

On the other hand, architects specifying tile in humid regions like south Florida and south Texas must be aware of the effects of mold and mildew which thrive in shady or moist areas. The problem can be reduced through proper drainage and a roof orientation that exposes shadowed and wet areas to sunlight. In Florida, fungus can collect on roofs, and the temperature never gets cold enough to kill it. Although the fungus does not damage the roof in any way, it can be unsightly. A soft pressure washing with a 5 percent bleach solution will help destroy the spores. Annual or biannual professional cleaning of mold and mildew is best performed by professional roof tile cleaners with the proper roof tile cleaning equipment and environmentally friendly cleaners.

Life Cycle Cost Considerations
Compared to other roofing materials, concrete roof tiles can be substantially more expensive to install. Due to their extreme durability, however, the cost of concrete roof tiles can be favorably distributed over an extended life cycle. Depending on the weather conditions and the quality of the installation, concrete tile roofs are virtually permanent roofs, meaning they can last 50 to 100 years or more - during which time wood, asphalt, and metal might be replaced up to three times. Because of the structural integrity and proven durability of concrete roof tiles, many leading roof tile manufacturers offer 50-year or limited lifetime product warranties, among the best in the industry.

For their own offices, Hill Foley Rossi and Associates, an architectural design firm in Duluth, Georgia, specified a flat concrete roof tile designed to look like slate but at a fraction of the cost. "It's a little less expensive than an authentic slate roof, but with the same qualities, " said Architect Mike Rossi, a principal with the firm. "You can have a concrete roof tile roof on your building for 50 years minimum, whereas with other materials like modified bitumen you will need to replace it in 20 years. Over the long run you save money because you have little to no maintenance with roof tile. " To complete the look of permanence, HFR combined heavy masonry products on the building's exterior walls and included heavy gable elements that give the 17,500-square-foot structure a craftsman-like lodge feel. "The roof is often the first thing people notice about our building," Hill said, noting that the aesthetic qualities of concrete roofing are becoming increasingly acknowledged in inland regions of Georgia and the Carolinas, where roof tile has not been as widely used as in coastal areas and in Florida.

 

Architects Hill Foley Rossi and Associates chose flat concrete roof tiles for their offices. Photo Courtesy of Hanson Roof Tile

 

 

HFR also specified the same tile on the Duluth City Hall, a building they designed about a mile from their office. "In the past couple of years we have fallen in love with roof tile," Rossi said. "The thick profile looks very solid; it gives a nice top to a building. We've tried other roofing products, but concrete tile gives depth and a nice profile to make for a very sound looking roof."

Maintenance
Concrete tile roofs are pest-resistant, do not rot in wet climates, are not damaged by heat or sunlight and resist fire and harsh weather better than other roofing products, particularly asphalt which harsh sunlight can cause to become brittle and weaken shingle adhesive, increasing the likelihood of shingles tearing or blowing off in bad weather. All roofs require some level of maintenance, with many roofing systems requiring coating, painting, cleaning, and/or sealing the majority of the roof surface. Under normal conditions, tile roofs require minimal maintenance mainly in the areas of gutters, flashings, and venting.

Occasionally a broken, cracked or missing tile must be replaced. When this occurs, the damaged tile can be removed and replaced in the same manner the other tiles are attached to the roof. If mechanical fasteners have been used and the nail or screw must be cut, care should be taken not to rip the underlayment. Foam attachments can be cut away. For best results, the replacement tile can be secured by a tile adhesive, a clip, or foam. If the underlayment is slightly torn, mastic can be used to mend the tear. Larger tears require new underlayment secured with mastic.