A cool roof is made with materials that naturally reflect sunlight, sending send solar waves back into the atmosphere. While most standard roofs absorbs the sun’s radiant energy into the building—transferring it as heat—cool roofs reflects the sunlight to keep buildings cooler. Made from a variety of materials, cool roofs can be applied to new and existing roof surfaces on houses, garages, and commercial buildings.
Why Cool Roofs?
Cool Your Home and Neighborhood
Cool roofs can provide enormous relief from the heat. We can all feel the difference in temperature between a tree-lined street and a barren stretch of wide sidewalk. Concrete, asphalt—and most roofs—capture the sun’s energy, holding it and slowly radiating heat back out. These kinds of surfaces contribute to the urban heat island effect. With a cool roof, the surface can be more than 50°F cooler during a hot summer day—cooling the interior of a building by several degrees Fahrenheit. The benefits: More comfort, and fewer chances of heat-related injuries or deaths. Even homes and other buildings without air-conditioning will stay cooler on the hotter days.
Reduce Your Energy Usage and Save Money
Dependent on an air conditioner to stay cool indoors? On sunny days, most standard roof surfaces retain heat into the night. When cool roofs reflect sunlight, they prevent the absorption of heat, allowing you to use less energy—and save on energy bills. Cool surfaces can also extend the life of the roof, substantially reducing costs over the life of the property.
Reduce Your Emissions
By using less energy, you are reducing the amount of greenhouse gases that are released into the atmosphere. Air pollutants are also decreased.
Prepare for Rising Temperatures
With the rise in temperatures as a result of climate change, we can all take steps to reduce energy usage, maintain comfort, protect health, and save money. UCLA’s Mid-Century Warming in the Los Angeles Region report shows that all areas of our region are projected to get warmer and we can expect the number of extreme heat days to rise substantially. In addition to the human health consequences of extreme heat, residents will soon be finding that they’re paying more just to keep themselves cool and comfortable.
Climate Resolve’s Work on Cool Roofs in Los Angeles
In working to help improve the climate resilience of Los Angeles with easy, common-sense policies to better our city, we launched a “Cool Roofs” campaign in 2012. A first step was bringing together dozens of experts, scientists, and leaders from across the country who are making great strides towards creating affordable climate solutions. At our March 2013 “Hot City, Cool Roofs” Conference, then-Mayor Antonio Villaraigosa laid out next steps for how cool roofs can improve Los Angeles today, tomorrow, and over the next century.
Climate Resolve and the participants of the conference identified a key takeaway from the conference: passing a law that required all new and refurbished homes to have a cool roof. On December 17th, 2013, Los Angeles became the first large city to pass such a law, which was unanimously approved by LA City Council thanks to the work of Climate Resolve. “Keeping temperatures down on extreme heat days will protect lives; energy efficiency will save millions of dollars; and cool roofs will help Los Angeles combat global climate change at the local level,” said Climate Resolve’s Executive Director Jonathan Parfrey after the bill passed.
For Angelenos: Getting a Cool Roof
Since 2014, all new residential construction and many major renovations have been required to install a cool roof. Cool roofs are compatible with other innovative, money-saving technologies, including solar panels and water catchment systems. Additionally, the Los Angeles Department of Water and Power (LADWP) offers up to a $.30 per sq. ft. rebate for residential roofs. This rebate was expanded to include more roofs types and applicable products in the City of Los Angeles. Find more from the “Building Products” section of LADWP’s Consumer Rebate Program page.
More Cool Roof Resources
Cool Roof Products
Below are a few available cool roofing product sources. Refer to the Cool Roof Rating Council‘s product directory for a more comprehensive list.
Cool Roofs Product Information from GAF (PDF)
Cool Roofs Product Information from Owens Corning (PFD)
PABCO Roofing Products (PDF)