Abstract

The living wall system (LWS) can improve the thermal behavior of the building envelope. The distance between the LWS and the wall has great influence on its cooling effect. This study tested the LWS’s cooling effects at different distances in a hot and humid climate in an controlled experimental setting and compared the cooling mechanisms of the LWS and the green façade. Two thermal labs installed with LWS at different distances were examined. The results show that between 30mm to 600mm, the smaller the distance, the better the LWS’s cooling effect. However, smaller distance slowed down the building wall from releasing heat to the ambient air at night. Smaller distance also resulted in higher humidity levels inside the air layer. Unlike green façades, the LWS creates a microclimate with a cool air layer and a cool surface (the backside of the LWS) that can significantly reduce the temperatures of the wall surface.