Urban heat island a built environment where the large portion of dark absorbing.
Solar reflectance index metal roofing.
The guide to choosing a cool roof.
Berridge s kynar 500 hylar 5000.
Installing a cool roof can cut your energy costs while contributing toward a better environment.
Emissivity is a material s ability to release absorbed energy.
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.
By lessening the demand for energy it decreases carbon emissions that cause pollution.
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.
Requirements and is calculated according to astm e 1980 using values for reflectance and emissivity.
Many homeowners elect a balance between solar reflectance and aesthetics.
Heat island effect roof.
Kynar 500 based painted metal roofing can achieve solar reflectance of over 70.
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.
New technology helps to close the gap between aesthetics and solar reflectance.
The cool metal roofing paint resin formula formulated by sherwin williams or another paint supplier contains innovative solar reflective pigments which is the key differentiator.
Reflected solar energy allows the roof surface to remain cooler which means less heat is transferred into the building.
Darker colors like dark brown have an average solar reflectance of 5 9 while white granules have a solar reflectance of 31 3.
The solar reflectance index is used for compliance with leed.
Also important characteristic to a metal building panel color is the ability of the panel to release absorbed energy called emissivity.
The benefits of cool metal roofing cool metal roofing has many benefits beyond savings on energy costs.
Cool metal roof colors are optimal for reducing energy consumption particularly where cooling loads dominate.
Cool metal roofing coated with kynar 500 based resin is one way to limit the urban heat island effect.
Furthermore it doesn t store as much thermal energy as an ordinary roof.
