CASE STUDY NATURAL STONE SOLAR REfLECTANCE INDEx AND THE URBAN HEAT ISLAND EffECT Prepared By The University of Tennessee Center for Clean Products. 2 Product solar reflectance emissivity temperature rise* srI Clay tile, red Concrete tile, red Concrete tile, white Asphalt shingles, white Limestone pavers** 0.33 0.18 0.73 0.21 0.53 0.9 0.91 0.9