Solar Reflectance Index Roofing Materials

California s building energy efficiency standards for residential and nonresidential buildings title 24 part 6 contains requirements for the thermal emittance three year aged reflectance and solar reflectance index sri of roofing materials used in new construction and re roofing projects.

Solar reflectance index roofing materials. Certainteed corporation has several solar reflective shingles to choose from in various style and color options to suit a range of different home styles and elevations. Only those roof products that meet the specifications. Cool metal roof colors are optimal for reducing energy consumption particularly where cooling loads dominate. Furthermore it doesn t store as much thermal energy as an ordinary roof.

To meet leed requirements a roofing material must have a sri of 29 or higher for steep slope 2 12 roofing and a sri value of 78 or higher for low slope roofing. Requirements and is calculated according to astm e 1980 using values for reflectance and emissivity. Compared to conventional roofing materials of lower reflectance index sri such as zincalume steel and all other roofing materials in the colorbond steel range. The solar reflectance index or sri is a calculation using the aged solar reflectance and thermal emittance measurements of the asphalt shingles materials.

Low slope roofs must have an initial solar reflectance of 0 65. The requirements apply to new construction and to retrofits or additions that replace or re coat at least 2 000 ft 2 of roof space for nonresidential buildings and 1 000 ft 2 of roof space for. Berridge metal roofing is cool and sustainable the high reflectivity emissivity and solar reflectance index sri of berridge metal roofing helps mitigate the heat island effect. The solar reflectance index is used for compliance with leed.

By lessening the demand for energy it decreases carbon emissions that cause pollution. Heat island effect roof. This measurement can be used as an indicator of how hot shingles are likely to become when they re exposed to the sun. The solar reflectance index sri is a measure of the solar reflectance and emissivity of materials that can be used as an indicator of how hot they are likely to become when solar radiation is incident on their surface.

After 3 years the solar reflectance must be 0 15. Berridge s kynar 500 hylar 5000. The solar reflectance index sri is a measure of the constructed surface s ability to reflect solar heat as shown by a small temperature rise. Installing a cool roof can cut your energy costs while contributing toward a better environment.

It is defined so that a standard black surface reflectance 0 05 emittance 0 90 is 0 and a standard white surface reflectance 0 80 emittance 0 90 is 100. Steep slope roofs must have an initial solar reflectance of 0 25. The lower the sri the hotter a material is likely to become in the sunshine. Emissivity is a material s ability to release absorbed energy.

The guide to choosing a cool roof. After 3 years the solar reflectance must be 0 50.