Comparação do desempenho térmico de revestimentos brancos

Abstract

Improving the thermal performance of buildings is a trend mainly caused by the need to reduce energy consumption. The radiative properties of the envelope’s coating determine its surface temperature, which directly affects the thermal performance. White coats are seen as an alternative to solve the problem of high cooling demand for buildings in cities with warm climate and minimize the urban heat island effect. This research analyses three white coats suitable for outdoor use in buildings, comparing their reflectance, emittance and surface temperatures. The results indicate that even coatings that seem to have the same colour may have different solar reflectance, resulting in different surface temperatures. The white coats showed differences of up to 10% on their solar reflectance. On the highest temperature day, the differences between the surface temperatures of white samples reached 8ºC. The use of materials with high reflectance in the near-infrared has proven to be an effective strategy to improve the thermal performance.