Cool Roofs

This fact sheet from the Environmental and Energy Study Institute (EESI) describes various cool roof technologies—including naturally cool, coated, insulated, and green roofs—and their benefits for energy efficiency, climate mitigation, and urban environment management.

• Cool roofs utilize different technologies to reduce heat absorption. Naturally cool roofs use white materials to increase albedo to 60 percent, compared to 10-20 percent for asphalt roofs. Coated roofs use solar reflective coatings, while insulated cool roofs combine high R-value insulation with reflective coatings to create a thermal barrier. Green roofs use plant life to provide environmental benefits, though they reflect less sunlight than other cool roof types.
• Cool roofs provide significant energy and cost savings. They can reduce air conditioning energy needs by up to 15 percent for single-story buildings and increase the energy production of photovoltaic (PV) solar installations by up to 16 percent by reducing surface temperatures. Upgrading U.S. commercial roofs with high R-value insulation is estimated to save over $2 billion annually.
• Cool roofs contribute to climate change mitigation and the reduction of the Urban Heat Island effect. A 1,000 square foot white roof can offset 10 tons of carbon dioxide over 20 years. On a global scale, whitening all eligible urban flat roofs could prevent 24 Gigatonnes of CO2 emissions. These roofs also lower city temperatures, which are typically 2°–10°F higher than rural areas, thereby reducing peak energy demand and heat-related illnesses.
• Green roofs offer specific environmental advantages beyond temperature control, including air purification and stormwater management. A 3-inch green roof can hold between 0.75 and 2 inches of rain. In Washington, D.C., greening 80 percent of rooftop space would reduce rooftop runoff by 56 percent, protecting watersheds like the Chesapeake Bay from pollutants.
• Specific implementations in Washington, D.C. demonstrate these benefits: the U.S. Department of Energy Headquarters white roof is expected to save $8,000 annually in energy costs; the American Society of Landscape Architects green roof retained nearly 75 percent of rainfall from May to July 2007; and the World Wildlife Fund Headquarters green roof helped the organization achieve a LEED Platinum Rating in 2011.

APA

Brock, S. (2012). Cool Roofs. Environmental and Energy Study Institute. https://www.eesi.org/files/cool_roofs_072412.pdf

Chicago

Brock, Samuel. Cool Roofs. Environmental and Energy Study Institute, 2012. https://www.eesi.org/files/cool_roofs_072412.pdf.

Wikipedia

{{cite report |last1=Brock |first1=Samuel |title=Cool Roofs |publisher=Environmental and Energy Study Institute |date=July 2012 |url=https://www.eesi.org/files/cool_roofs_072412.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{brock2012cool, author = {Brock, Samuel}, title = {{Cool Roofs}}, institution = {Environmental and Energy Study Institute}, year = {2012}, month = jul, url = {https://www.eesi.org/files/cool_roofs_072412.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }