Design of a cool color glaze for solar reflective tile application

Solar reflective materials, so called cool roofs, can be identified as one of the most promising solutions to counteract urban heat island. Cool roof market is nowadays dominated by polymeric product, which can ensure good optical properties but poor durability against weathering and ageing. Ceramic-based products can be an excellent solution combining both good solar properties and higher durability against time, in particular if glazed. Embedded colored pigments, moreover, can help the introduction of these materials in Mediterranean building policies. These cool colored ceramic-based products, in fact, match naturally high thermal emissivity (ε=0.90) with higher mechanical, chemical and physical durability. A traditionally engobed porcelain stoneware tile was used as a substrate for a new generation of colored glazes characterized by different surfaces reaching promising values in solar reflectance.