Sri Roof Rating

Higher sri ratings for shingles mean greater reduction in cooling load on a home.

Sri roof rating.

Numbers from 20 to 90 are typical but it s interesting to note that sri can be more than 100. Leed 2 2 sustainable sites credit 7 2 states that to receive one point building owners should use a roof with a solar reflective index sri of 78 over at least 75 percent of the roof s surface for roofs with slopes less than 2 12. Solar reflectance is the amount of solar energy or uv rays that is reflected away from the building back into the atmosphere. Incorporates both solar reflectance and thermal emissivity in a single value.

Metal roof sri ratings. Solar reflective index sri is important to understand when selecting a highly reflective roof coating that will help lower energy cooling costs. Asphalt shingle products with an energy star rating do not utilize the sri compliance path. Sri is a unit developed by scientists at lawrence berkeley national laboratory.

These ratings are presented below. According to the manufacturer they quote ornl as saying it does help. Solar reflectance index sri. Does having a cool roof help with the r value of roof assembly.

In addition to a description of what they like and dislike about their shingles homeowners also rate their satisfaction from 5 very satisfied to 1 very unsatisfied. Asphalt roofing shingles with higher sri ratings are cooler in the sunshine. Peter l posted in energy efficiency and durability on april 12 2015 09 40am if a cool roof design has a sri of 40 would going for a sri of 54 make that much more of a difference. Recycled content of berridge metal.

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. In fact this is fairly is common for highly reflective products with high emissivity for example light colored asphaltic membranes like gaf energycap. To meet leed requirements a roofing material must have a sri of 29 or higher for steep slope 2 12 roofing and a sri value of 78 or higher for low slope roofing. The sri is a calculation method using solar reflectance and thermal emittance values to determine the roof s overall capacity to refuse solar heat.