Metal Roof Solar Reflectance Index

Solar reflectance index sri.

Metal roof solar reflectance index.

For every 10 increase in roof reflectance heating cooling costs drop 2 cents per square foot per year. 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. The sr value is a number from 0 to 1 0. If the percentage is a higher number that means the surface is more effective at reflecting the radiation from the sun.

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. 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. Total solar reflectance tsr refers to the method of measuring a surface coating s reflective capability. Recycled content of berridge metal.

Heat island effect roof. 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. What does tsr mean for my roof. Tsr is usually displayed as a percentage between 0 and 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. 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. Incorporates both solar reflectance and thermal emissivity in a single value. This is called the solar reflectivity index sri.

Also important characteristic to a metal building panel color is the ability of the panel to release absorbed energy called emissivity. Keep in mind these numbers will vary based on location and utility costs but still offers a good representation of how cool metal roofing with a high solar reflectance can help a consumer save on their energy bills. Wavelengths on a scale of 0 to 1. A value of 0 indicates that the material absorbs all solar energy and a value of 1 0 indicates total reflectance.