To assess the effect of uneven tiled surfaces on solar reflectance, a numerical calculation was utilized to estimate the solar reflectance of several kinds of surface shapes. In addition, the relationship between solar reflectance of uneven surfaces and surface shapes was analyzed. Drawing on the calculation results, the reduction of solar reflectance from the flat surface was also estimated. A heat budget model of the tile surface and sectional direction of the roof system was developed on the basis of observation results relating to the thermal characteristics of a traditional tiled roof system. A comparative simulation with other urban heat island mitigation technologies, such as green roofs, was carried out under typical weather conditions. (C) 2011 Elsevier B.V. All rights reserved.