Metal Roof Solar Reflectance Index

To meet leed requirements a roofing material must have an sri of 29 or higher for steep slope roofing and a value of 78 or higher for low slope roofing when evaluated under medium wind conditions.

Metal roof solar reflectance index.

Also important characteristic to a metal building panel color is the ability of the panel to release absorbed energy called emissivity. Heat island effect roof. The sr value is a number from 0 to 1 0. Incorporates both solar reflectance and thermal emissivity in a single value.

If the percentage is a higher number that means the surface is more effective at reflecting the radiation from the sun. For every 10 increase in roof reflectance heating cooling costs drop 2 cents per square foot per year. Anodized aluminum clear anodized aluminum can play a significant role in cool roof design because of its higher solar reflective index sri solar reflectance and thermal emittance than for example white polyvinylidene fluoride pvdf painted aluminum. Recycled content of berridge metal.

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. Tsr is usually displayed as a percentage between 0 and 100. Solar reflectance is also called albedo. Sri measures the roof s ability to reject solar heat defined such that a standard black reflectance 0 05 emittance 0 90 is 0 and a standard white reflectance 0 80 emittance 0 90 is 100.

This is called the solar reflectivity index sri. What does tsr mean for my roof. 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. Leed requires a roofing material to have a value of 29 or higher for a steep roof pitch 2 12 and 78 or higher for a roof pitch 2 12.

Energy star requires an initial sr value of 0 25 or higher for steep slope 2 12 roofs and 0 15 or greater after three years. A value of 0 indicates that the material absorbs all solar energy and a value of 1 0 indicates total reflectance. The solar reflectance index sri is used to determine compliance with leed requirements and is calculated according to astm e 1980 using values for reflectance and emissivity. Wavelengths on a scale of 0 to 1.