AUSTIN (KXAN) — The City of Austin is sharing data with Google on the solar reflectivity of roofs across the community to better understand which parts of town would benefit most from cool roofs, a type of roofing that reduces heat in homes and neighborhoods.
Laura Patiño, the chief resilience officer at the city of Austin, described solar reflectivity as the measure of how much sunlight a roof can reflect. A higher reflectivity means your home is absorbing less heat.
Once the city is done studying the roofs across multiple neighborhoods, it will then be able to use that data to find which areas of town would benefit the most from cool roofs, and could shape some future policy. The data will be a part of Austin’s heat resilience playbook, a tool to reduce urban heat in the city.
“From creating awareness and communicating and educating to residents what they can do to their homes, all the way to creating policies and new standards for how we build in our city that will make our city more adaptive to the changing environment,” Patiño explained.
What are cool roofs?
Cool roofs are exactly what they sound like: Roofs that keep your home cooler.
Solar reflectivity depends on three different aspects: color, material, and the shape of your roof. Patiño said a lighter-color roof will be better at reflecting sunlight. Think about what you wear on a hot day. If your clothes are darker, you will be absorbing more heat than if you wore light colors.
Material also plays a bigger role. There are certain materials that are found to reflect better. The Department of Energy lists a couple of materials that reflect light more. Some of the options include wood shingles, light-colored asphalt shingles, and clay tiles.
Shape will play a role too, Patiño said. A flat roof will not reflect light as well as sloped roofs.
Not only keeping you cool, but saving you money
Because cool roofs are designed to reflect more light and reduce the heat absorbed by your home, it is going to save you some money on electricity costs. A Department of Energy study found cool roofs “reduce the annual air-conditioning energy use of a single-story building by up to 15%.”
“You’re talking about less energy consumption, because when your home is reflecting that heat it isn’t getting as hot inside, so you’re looking at lower electricity bills. You’re also looking at better quality of life,” Patiño explained.
Cool roofs will not only keep your home cool, but will reduce the amount of urban heat in your community. Patiño said that can make your walk from your front door to a bus stop much more comfortable.