Metal Roofing Solar Reflectivity Index
The Solar Reflectance Index or SRI is a measure of the roof’s ability to reject solar heat. In roofing it is used to determine compliance with LEED requirements. Materials with the highest SRI values are the coolest choices for roofing. These values are calculated according to ASTME 1980 using values for reflectance and emissivity. To meet the requirements from LEED, the roofing material must have an SRI of 29 or higher for steep slope (above 2:12) roofing and an SRI value of 78 or higher for low slope (2:12 or less) roofing. For more information, please go to www.usgbc.org.