Extreme heat throughout the United States this summer is re-emphasizing the importance of cool roofing. Cool roofs — those that are light-colored and reflect the sun’s heat — have three key benefits for facility managers and the community at large.
First, cool roofs can benefit individual building owners with savings on air conditioning costs. Owners probably are familiar with this benefit because it has been the major focus of most cool roof marketing for a long time. The amount of energy saved depends on a number of factors, including amount of insulation, roof assembly, location of facility, and the type of facility.
Second, cool roofs and other reflective surfaces can help mitigate the urban heat island effect. This benefit accrues to the entire community because if the temperature is reduced a few degrees on hot summer days, everyone uses less energy for air conditioning. Several studies are underway that seek to quantify the exact amount of energy that can be saved if a particular percentage of surfaces in a city change to reflective.
Third, similar to the way cool roofs can help mitigate the urban heat island effect, cool roofs also can help slow warming induced by climate change. Reducing the global surface temperature only a few fractions of a degree through the use of cooler surfaces could produce a tremendous offset in terms of carbon emissions and the resulting warming they cause. One researcher at Lawrence Berkeley National Laboratory concluded that raising the worldwide albedo – or reflectance – by 0.0003 would have the equivalent of offsetting 44 billion metric tons of carbon dioxide.
This Quick Read was submitted by Greg Zimmerman, executive editor, Building Operating Management. Read his recent story about the new LEED v4.1 rating system.
