When cool-roof materials enter a discussion, the tendency is to think of them as a class of products that fit best in
sun-drenched, high-annual-temperature portions of the country. Research, however, tells us that the benefits of Cool Reflective Roofs can be realized in all climate zones.
Cool-roof materials, which have been in use since the 1960s in Europe and the 1970s in North America, reflect a significant portion of incident solar radiation back into the atmosphere (reflectance), and also quickly release to the atmosphere the fraction of energy that the roof absorbs (remittance). Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA, was one of the first to measure the cooling energy savings associated with cool roofs. LBNL’s 2001 study of an Austin, TX, retail store found that switching a black-colored membrane to a white membrane reduced the facility’s average summertime rooftop surface temperature from 168 F on the black to 126 F on the white. Peak-hour cooling- energy savings were at 14% and overall annual energy savings were $0.072/sq. ft. Adjusted for inflation in 2013, this would be the equivalent of $0.095/sq. ft. Continue reading