Monitoramento e determinação de índices de desempenho térmico de um telhado verde extensivo em escala real

Abstract

Green roofs have proven hydrological and thermal benefits. In view of the large roof area available in urbanized areas, green roofs are an alternative to mitigate the effects of urbanization such as soil sealing and the emergence of heat islands, in addition to contributing to a better thermal performance of the buildings in which they are located, generating energy savings by reducing the need for air conditioning. The present work presents the result of the thermal monitoring of an extensive green roof in full scale, composed of sandy substrate and bromeliad vegetation, interspersed with paths executed in crushed stone and wooden deck. Monitoring consisted of collecting data on internal temperatures of the green roof, internal and external to the building, in addition to photographic analysis of the roof with a camera. From this monitoring, temperatures of interest (maximum and minimum) and thermal performance indices (thermal amplitude and thermal delay) were determined. It was inferred that the roof has regions of great heating due to the different materials used in the roof, and does not present a good attenuation of maximum temperatures. This fact can be explained by the composition of the green roof, with materials that have a high capacity for absorbing and retaining heat, in addition to the low percentage of vegetation cover.