Residential Roofing Solar Reflectance

Reflective surfaces are a form of geoengineering.

Residential roofing solar reflectance. These shingles must have an initial solar reflectance of at least 0 25 and a three year solar reflectance measurement of at least 0 15. How they can be made cool. Painting a metal roof can increase its solar reflectance and thermal emittance allowing it to achieve cool roof status. Solar reflectivity or reflectance is the ability of a material to reflect solar energy from its surface back into the atmosphere.

Feature gaf proprietary color blends and enhanced shadow effect for a genuine wood shake look. Alternatively you can apply cool reflective coatings. Residential roofing options include asphalt shingles metal clay tiles and concrete tiles. Reflective surfaces can deliver high solar reflectance the ability to reflect the visible infrared and ultraviolet wavelengths of the sun reducing heat transfer to the surface and high thermal emittance the ability to radiate absorbed or non reflected solar energy.

A value of 0 indicates that the material absorbs all solar energy and a value of 1 0 indicates total reflectance. Solar reflective shingles. 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. This is a requirement in some energy codes.

Solar reflectivity r solar reflectance index sri by color. Unpainted metals are typically good solar reflectors but poor thermal emitters so they rarely satisfy low slope cool roof requirements. Innate reflectance is measured on a scale from 0 to 1 with the latter being the highest level of reflectivity meaning it reflects 100 of all radiant energy coming in contact with it. All of these types of residential roofing products are now available with ir reflective color pigments which act to reduce the temperature of roofs and reflect heat away from the home.

Cambridge tm cool colors reflect a percentage. Owens corning asphalt shingle products labeled as cool are rated with the cool roofing rating council ccrc for solar reflectance and thermal emittance. The sr value is a number from 0 to 1 0. Meet the prescriptive solar reflectance and thermal emittance requirements according to the 2016 title 24 standards are rated by the cool roof rating council and meet the cool roof requirements of the los angeles green building code find out more about title 24 here.

Solar reflective shingles and solar reflective roofing membranes can be an important component in a building system designed to reduce overall building energy consumption and the impact the home or building has on the environment. As you re shopping for your new roof look for the tag or label solar reflectance.