Dear All,

One of our clients is pursuing compliance with requirements for pavings (SR at least 0.28, 3 years aged or initial SR of at least 0.33) and one paving manufacturer proposed the following measurements methodology for SR determination:

  1. Determination of the solar reflectance in accordance with ASTM E903-12. The solar reflectance is calculated using the selected ordinate method set out in Section 8.3.4. Ordinates are selected from the values of direct normal solar irradiance specified in Table X2.3 of ASTM E903-12 «50 Selected Ordinates for G173 Direct Normal Irradiance AM 1.5»
  2. Determination of the emissivity in accordance with ASTM C1371-15 

Carrying out these two tests, a report is issued where the SRI according to ASTM E1980 – 11 will be shown. Based on the previous measurements made, the surface temperature and the SRI for each specimen will be determined.

Specimens required: a total of 3 specimens of minimum dimensions (100 x 100) mm. Regarding their shape it is essential that the specimen can be placed vertically and no material drops from it; the area to be measured shall be continuous (with no holes) and flat, so a big single stone will be best. If you have any 0/x grading, I propose to prepare a specimen using colourless polyester resin and grind the surface.

Is this methodology acceptable for determine the SR of pavings that can be contribute for nonroof measures eligible for SS C5 Heat Island Reduction Credit compliance?

Thanks in advance,