Solar Reflectance Index Calculator (SRI)

The purpose of this calculator is to enable contractors and homeowners to quickly and accurately calculate the solar reflectance index (SRI) of their roof for showing compliance with the California Building Energy Efficiency Standards.

The 2008 Building Energy Efficiency Standards allows compliance with the prescriptive cool roof requirements, either by meeting prescriptive requirements for the aged reflectance and initial thermal emittance requirements, or alternatively, by meeting the required SRI value, which is dependent on the roof slope and the total weight of the roofing material.

The SRI alternative is useful when a particular product exceeds the Building Energy Efficiency Standards requirement for either the aged solar reflectance or the initial thermal emittance, but does not meet both requirements. In this case the combination of the aged solar reflectance and the initial thermal emittance for the product may be sufficient to comply with the SRI requirement.

For more information about the SRI Calculator, please contact the Energy Standards Hotline.