Solar Reflectivity

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Solar Reflectivity (SR): Solar reflectivity or reflectance is the measure of a material's ability to reflect solar energy or sunlight from its surface.

 

SR values are numbered 0 to 1.0. A value of 0 indicates that the surface absorbs all solar energy and a value of 1.0  indicates total reflectance.

 

ENERGY STAR requires an SR value of 0.25 or higher for steep slope roofing (above 2:12) and an SR value of 0.65 or higher for low slope roofing (2:12 or less).

 

 -- For more information, please visit www.energystar.gov.

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Solar Reflectance Index (SRI): The SRI is used to determine compliance with LEED requirements and is calculated according to ASTM E 1980 using values for reflectance and emissivity.

 

To meet LEED requirements, a roofing material must have an SRI of 29 or greater for  steep slope roofing and an SRI value of 78 or higher for low slope roofing.

 -- For more information, visit www.usgbc.org.