In the next several years, energy codes across the nation may start to incorporate reflective—or “cool”—roofing requirements for low-slope-roof commercial buildings to help reduce energy consumption, according to industry experts, and a handful of energy codes—including California, Chicago, and Austin, Texas—already have mandates. And when it comes to energy conservation, performance requirements that begin in the commercial sector frequently filter down to residential applications.
Cool roofing products—metal or asphalt—use specialty paint coatings or specialty granules to reflect solar radiation away from the roof surface to reduce temperatures in the space below, helping to reduce cooling loads. Solar reflectance is expressed as a value between 0 and 1 or as a percentage; roofing with a value of .25, for example, reflects 25 percent of the solar radiation reaching the roof. Light colors reflect the most radiation.
Though the residential cool roofing market shows every indication of growing, manufacturers say, since most codes do not yet mandate reflectivity requirements for steep-slope/residential roofs, demand has been low. Currently the only national reflectivity criteria for steep-slope roofs are set by Energy Star (.25), a voluntary program. California's energy code is expected to set reflectivity requirements for steep-slope roofs in 2008, according to Mike DiStefano, director of marketing for GAF (circle 102). Often, initiatives that start in California spread to other states.
Unless they are actively seeking green products, most pros and homeowners are likely uneducated about cool roofing. “Not many people are aware of it yet, but it's an interesting movement,” says Tony Chiovare, president of Custom-Bilt Metals (circle 103). “It's gathering substance as it rolls down the road.” In fact, as energy costs have gone up, manufacturers say they have received a corresponding increase in residential inquiries.
Product availability and cost also have been barriers to widespread residential use of cool roofing. While manufacturers like Custom-Bilt Metals, Classic Metal Roofing Systems, Ultra Seam, Dura-Loc, Met-Tile, Englert, Fabral, Metal Sales Mfg., and others are able to offer metal roofing in the dark colors homeowners crave and with high levels of reflectivity, metal roofs are more expensive than standard asphalt roofs. Asphalt currently offers the fewest cool-colored options. Some white and very light-colored asphalt shingles available from CertainTeed, GAF, Owens Corning, and IKO offer relatively high reflectivity levels (between .15 and .28), but most homeowners prefer darker roof colors. Last year Elk Corp. introduced asphalt shingles in mid-tones with reflectivity levels of .26 and .27 using reflective granules from 3M, and the company is working on darker versions. Asphalt shingle manufacturer Tamko says it will be introducing a cool roofing shingle this year, as well. Others likely have products in development.
Some manufacturers predict the residential cool roofing market will take off dramatically, while others expect slower growth. “Initially, the market will be in the Sunbelt states,” says Mike McClintock, Elk's marketing director, “but we think over time, with energy prices rising, homeowner ‘care-abouts' changing, and new legislation, the need for alternatives to traditional roofing will be in demand throughout the country.”