Roofing With 3 Years Minimun Reflectance

California s building energy efficiency standards for residential and nonresidential buildings title 24 part 6 contains requirements for the thermal emittance three year aged reflectance and solar reflectance index sri of roofing materials used in new construction and re roofing projects.

Roofing with 3 years minimun reflectance.

The doe uses the low sloped cool roof definition from table 1 and defines steep sloped cool roofs as those with a 3 year aged sri of 29 or greater. The requirements apply to new construction and to retrofits or additions that replace or re coat at least 2 000 ft 2 of roof space for nonresidential buildings and 1 000 ft 2 of roof space for. Only those roof products that meet the specifications listed in either table 1 or table 2 below may qualify as energy star qualified. Steep slope roofs must have an initial solar reflectance of 0 25.

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. 0 65 initial 0 50 aged. If you re following iecc you have a couple of options for roof materials. The energy star program specifies minimum solar reflectance low slope.

Effective january 1 2010 the standards will require that a cool roof material meet an aged solar reflectance value 3 year testing provided by the cool roof rating council crrc. After 3 years the solar reflectance must be 0 15. Owens corning asphalt shingle products labeled as cool are rated with the cool roofing rating council ccrc for solar reflectance and thermal emittance. Materials lacking 3 year aged tested values for either solar reflectance or thermal emittance shall be assigned both a 3 year aged solar reflectance in accordance with section c402 3 1 and a 3 year aged thermal emittance of 0 90.

Aged solar reflectance tested in accordance with astm c 1549 astm e 903 or astm e 1918 or crrc 1 standard. After 3 years the solar reflectance must be 0 50. You can install one with a three year aged solar reflectance index sri of 64 or you can instead opt for one with an aged sri of 55 combined with an aged thermal emittance of 0 75 or. Reflectance refers to the roofing material s ability to reflect the energy coming from the sun instead of absorbing it.