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A New Look for Metal Roofs

Hurricane Ivan slammed into the Gulf Coast and the Florida panhandle on Sept. 16, 2004, packing 120-mile-per-hour winds. The storm did more than $13 billion in damages before the skies cleared. It tossed a section of Interstate 10 in Pensacola into Escambia Bay. It killed 14 people. One thing Hurricane Ivan did not do was tear the roof off the house Bill Fette was building, half a mile from the Gulf of Mexico. The roof on Fette's new house in Pensacola looks like tile but is made from stone-coated steel. It's part of a new generation of metal roofs that promises to be lighter, stronger and longer-lasting than more popular roofing materials, namely asphalt shingles. Today's metal roofs don't promise to be inexpensive, however.
They are typically two to three times the installed cost of asphalt. Fette's roof cost $29,700, or $450 per square (100 square feet). But the coated steel tiles carry a 50-year limited warranty. He figures it's the last roof he'll ever install. "My wife was real hesitant at first, because it was so expensive," Fette says of his decision to invest in a metal roof. "But after the hurricane came through and she saw there was no damage, she said it was well worth it." Regional Growth Experiences like Fette's are helping to fuel the growth spurt in homes with metal roofs. According to the Metal Roofing Alliance (http://www.metalroofing.com), the number of homes in the United States and Canada with steel roofs has doubled in recent years. They now make up more than 8 percent of the reroofing market. Nationwide, metal is not likely to overtake asphalt, which can be found on six out of 10 homes.
 
But metal is making strong regional inroads, especially where homeowners are on guard against natural disasters. Growing markets include Florida and the Southeast, where hurricanes threaten; California, where wildfires can ignite cedar shakes and earthquakes can collapse concrete tiles; and Texas, where steel's resistance to hail can reduce property insurance premiums. Growth is taking place despite the stereotypes of metal roofs. Maybe it's a childhood memory of summer camp, with rain pounding on a tin roof. Perhaps it's the image of old farm buildings, with rusty, corrugated roofs. That's how Fette used to think of metal roofs. "I'm from Texas," he says, "and that's what you put on a barn." The familiar standing-seam metal roof - constructed of vertical interlocking panels with raised seams where the panels join - is still available. But technology has transformed the look and durability of metal roofs, creating styles and profiles that are difficult to distinguish from traditional shingles, tiles and shakes. Today's stone-coated metal roofs use advances in acrylics and chemistry to create architectural surfaces that look like wood or concrete tile, but are lighter and long-lasting. In California, metal shakes and shingles are strong sellers, replacing cedar in wildfire areas.
 
Tile styles are popular in Florida, shingles in the Midwest and standing-seam panels in the snowy North, according to Peter Croft, vice president of sales and marketing at Metro Roof Products. In each region, metal roof businesses are making a pitch for how their products can withstand the extremes of local weather conditions. Croft also makes a case for metal roofs in earthquake-prone areas. The reason: Metal roofs weigh about 1.5 pounds per square foot installed. That compares with roughly 10 pounds for concrete tile and 3 pounds for asphalt. Homes with lightweight roofs have a better chance of surviving earthquakes, according to cases Croft describes. That's because the walls on a typical home are designed to bear the weight of a heavy roof but not the shaking that accompanies an earthquake. Benefits and Misconceptions Still, stereotypes are hard to overcome. That's why a collection of manufacturers, roofing firms and chemical companies teamed up to form the Metal Roofing Alliance, which is spending $2 million a year to promote steel roofs. Their primary message is for existing homeowners, because an estimated 7 million homes will need new roofs this year. "It's an investment in your house, not just a repair," says Bill Hippard, president of the alliance and vice president for sales at Precoat Metals in St. Louis.
 
Hippard's group is trying to get homeowners to focus on lifecycle costs, not just the installation cost of metal roofing. To make his point, he offers this example: A home in South Carolina has a roof covering 43 squares (4,300 square feet). The installed cost of a vertical-panel metal roof is $9,460. A premium asphalt roof is half that price - $4,515. But every 15 years, the MRA calculates, the asphalt roof needs to be replaced. By contrast, the metal roof needs no maintenance. After 60 years, the price of the metal roof is unchanged, while reroofing with asphalt will cost $34,615. This is a simplistic example, to be sure. It doesn't account for the lost value over time of money spent on a more expensive installation, and it assumes an asphalt roof is shot after 15 years.
 
But the MRA is promoting the install-it-and-forget-it value of a maintenance-free metal roof. It cites evidence of added resale values for homes with steel roofs, and the potential for air-conditioning savings from reflective, white steel roofs in hot climates. Some metal roofs even qualify for the government's Energy Star certification, which aims to reduce energy costs by 30 percent. That might be surprising, because metal is conductive. Thinking perhaps of an old barn, one might figure the roof would be hot in summer and cold in winter. But at Fette's house, for instance, the roof is installed over 5 inches of foam insulation. On existing homes, metal roofs typically are vented and installed over asphalt shingles, so if anything, thermal comfort increases. The misconception about temperature and conductivity is one of several challenges the industry faces. The questions are so common that the MRA has addressed them head on. Its website includes a section called Myths Uncovered, which responds to concerns about lightning strikes, noise, dents, rust and durability.
 
To summarize those points, metal roofs don't increase the likelihood of lightning strikes, and they will disperse the energy if they are hit. Stone coating, air spaces and insulation make modern metal roofs quiet. Hail and heavy weather won't bother modern metal roofs, which carry a 120-mph wind rating. Additives in the manufacturing process prevent rust and corrosion. Making a Metal Roof Metal roofs are made of numerous layers. Decra Roofing Systems (http://www.decra.com), for instance, starts with panels of structural-grade steel strong enough to walk on. Then comes an aluminum-zinc alloy coating, which protects against corrosion; an acrylic priming system; and a basecoat that protects against water and ultraviolet light, and acts as a bonding agent for the stone coating layer. Stone coating is most popular in residential applications. Decra uses ceramic-coated granules to further protect against UV light and water erosion. Over that is a final layer, an overglaze that bonds to the granules and protects the roof from physical damage.
 
For his house, Fette chose a metal roof from Metro Roof Products (http://www.metroroofproducts.com) of Oceanside, Calif. Metro uses specially graded stone chips produced by 3M. The granules are embedded in an acrylic polymer that is resistant to ultraviolet rays and bonds to the steel. To protect the steel substrate from rust and corrosion, layers of metallic and polymer coatings are applied. Beyond protection, the stone coating creates an architectural appeal that's popular with homeowners. "You would be hard pressed to tell it's a metal roof," says Croft. Investing in a Roof The biggest challenge for the metal roof industry is that American homeowners are mobile. They move, on average, every seven years. Because 90 percent of the metal-roofing market in the United States is for existing homes, the industry has to convince buyers who move every seven years to invest in a roof that lasts 50 years. Two target groups are retirees and baby boomers. Many are investing heavily in their homes and making long-term commitments. "A large percentage of people putting on metal roofs plan to stay in their homes for the rest of their lives," Hippard says. "They don't want to worry about their roofs 15 or 20 years from now."
 
The MRA has set a goal of capturing 12 percent of the North American reroofing market share by 2009. To meet its goal, the industry will have to find more converts like Fette of Pensacola. With the warnings about Hurricane Ivan, Fette locked the doors on his two-story stucco-sided house and evacuated the area. The house has shatter-resistant glass, so he wasn't too worried about windows, but he did wonder about the roof. When the storm passed, Fette returned to his neighborhood to see asphalt roofs stripped off by the punishing winds. Except for some damage to a vinyl soffit, Fette said his metal tile roof appeared untouched. "I wanted something that would withstand a hurricane," he says. Looks like he made the right choice. Tux Turkel wrote about building-integrated solar panels in the July/August issue. He's based in Yarmouth, Maine.