With energy costs soaring, many Americans want to improve their home’s efficiency, and a new roof can make a big difference. But when taking into consideration your clients’ budgets and the eco-friendly features of any given roofing material, it quickly becomes clear that not all roofs are created equally. Experts say installing a reflective roof, which diverts the sun’s rays away from a building, is key to reducing heating and cooling expenses while also making a structure more environmentally friendly.
How does reflective roofing work?
Reflective roofs reduce the absorption of the sun by deflecting solar rays away from a roof, which can dramatically lower the surface’s temperature. On a warm day, a conventional roof can hit 150°F, while a reflective roof can lower that temperature by 50°F, according to the U.S. Department of Energy (DOE).
“By reducing the level of this warmth transfer, solar-reflective shingles and solar-reflective roofs can keep building interiors much cooler, therefore minimizing the usage and stress on HVAC equipment—especially in warmer areas and in the summertime,” explained Chad Newbauer, sales advisor for Highland Contractors, a residential and commercial contracting firm headquartered Rochester, N.Y.
Two factors determine a roof’s reflective capabilities: solar reflectance and thermal emittance. These measure a roof’s ability to deflect solar rays and keep cool, and materials are scored on a scale of 0 to 1, with 1 being the most reflective. A roof with good reflective roof should have both high solar reflectance and high thermal emittance. To help guide roofing contractors and consumers, the Cool Roof Ratings Council measures and scores materials and provides educational materials.
What materials are used on reflective roofs?
Also known as cool roofs, reflective roofs can feature asphalt shingles, clay tiles, concrete or metal. A white roof is the most reflective, diverting about 60%–90% of sunlight, while a light-colored roof reflects about 30%–60%, according to the DOE.
How do reflective roofs help your clients?
Most importantly for many clients, a reflective roof can help consumers save on their energy bills. According to the Environmental Protection Agency, cool roofs provide annual savings on heating and cooling of almost 50 cents per square foot. Additionally, the DOE notes that a cool roof is comparable in price to a conventional roof, making it an easier sell for your budget-conscious clients.
To more easily explain such details to homeowners, Kurt Ulrich, owner of Denver-area The Colorado Roofing Company, begins by asking clients to imagine standing on a paved driveway or parking in direct sunlight on a hot summer day, and then visualize moving into a shady spot on the grass under a leafy tree.
“The heat absorption and retention are very noticeable, and a dark roof surface acts the same way,” Ulrich said.
A reflective roof may also last longer, giving homeowners more bang for their buck. Over time, experts explained, the sun’s ultraviolet rays can degrade the quality of a conventional roof, including compromising granules on asphalt shingles. And as weather conditions change and a roof continually expands and contracts, it can compromise the durability of the roofing materials.
“Reflective roofs should be expected to have a longer life expectancy than darker roofs that absorb more energy,” Ulrich said. “A highly reflective roof that absorbs less energy is going to put less demand on the cooling system of the building, helping to increase the longevity of that system as well."
Are there any downsides?
Because it deflects solar energy, reflective roofing could result in a “winter penalty,” where the home or building owner must pay more to maintain a comfortable temperature in the colder winter months.
To maximize the benefits of reflective roofing in any location, contractors should consider recommending that clients also upgrade a building’s attic ventilation and insulation, said Jason Bellflower, corporate operations manager for Florida-based Tadlock Roofing.
“Whether it is a cold or hot environment, the insulation above a heated or cooled space is one of the most important considerations to make when seeking efficiency,” he said, noting also that proper ventilation allows for better air circulation while insulation helps further regulate temperature.