Metal Roofing Reflectance Values

According to the lawrence berkeley national laboratory.

Metal roofing reflectance values.

Solar reflectance values are determined by means of a solar spectrum reflectometer in accordance with astm c 1549. Reflected solar energy allows the roof surface to remain cooler which means less heat is transferred into the building. These values usually are listed in decimals with 0 99 being the best and 0 000 being the worst. For every 10 increase in roof reflectance heating cooling costs drop 2 cents per square foot per year.

Its relative reflectivity is much greater than surrounding surfaces. Use this chart to help you choose the best finish for your project. This characteristic of metal roofing is the most important in terms of energy savings. New products must have an sr value of 0 25 or higher for steep slope roofing above 2 12 and an sr value of 0 65 or higher for low slope roofing 2 12 or less.

Resources metal reflectivity chart with metals it is often desired to have a reflective surface not necessarily blindingly bright but one that catches the eye. Compare sri values to find the best finish for your project. A gold leaf surface shimmers in the sunlight like a beacon when se. The deduction applies to roofs installed between january 1 2011 and december 31 2020.

Tax credits energy efficiency federal tax credits homeowners can receive a tax credit of 10 of the cost up to 500 for interlock metal roofing systems installed on their principal residence. Kynar 500 based painted metal roofing can achieve solar reflectance of over 70. 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. Berridge metal products have a high recycled content and are 100 recyclable at the end of their lifespan.

Cool metal roofing coated with kynar 500 based resin is one way to limit the urban heat island effect. Astm standards e903 and e1918 are used to measure the solar reflectance values. Most roof manufacturers have total reflectance and thermal emittance values listed for their various roofing colors and finishes. Recycled content of berridge metal.

For every 1 increment in roof reflectance the surface temperature of the metal roof decreases 1 degree fahrenheit. Energy star requires sr testing of both new and aged roof products.