Effectiveness of an intensive green roof in a sub-tropical region

Abstract

The overall assessment of an intensive green roof located in a sub-tropical region has been undertaken. The results showed a fairly good agreement between the published and measured solar radiation data and also confirmed July and January as the hottest and coldest periods, respectively, for the region. The soil was established as a silt type with good planting medium properties for green roofs. The overall thermal performance showed that the green roof provided an average temperature reduction of 3.3℃ (i.e. 50% temperature reduction) through the roof in July. Equally, its performance was remarkable during the coldest period of January. A maximum differential temperature of 15.5℃ was achieved with the soil contributing to 24% of the temperature difference through the roof. Further studies are, however, needed to cover a wider area of influence such as effects of different types of construction materials, plants, locations and soil. In view of the limitation of the theoretical model, it would also be useful to consider some of the factors which were either neglected or assumed to be constant in any future comparative studies.

Keywords

Green roof energy storage soil thermophysical properties sub-tropical

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