Assessing urban heat island mitigation using green roof

Abstract

Sustainability development is one of the main significance nowadays throughout the world. The appropriate building design strategy of construction process contributes to reduce the energy consumption of the building. Green roof can play a positive role to reduce the roof surface temperature and air temperature that contributed into energy saving. The purpose of this research is to investigate the heat performance of the green roof and the changes that occurs for indoor heat surrounding during hot weather condition especially for urban area in Malaysia. This research was conducted through field measurement and monitoring in Perlis, and the selected areas are Kangar, Jejawi and Padang Besar. The measurement involved the monitoring of temperature and the relative humidity twice a month starting December until April 2015. The main significance of the monitoring is to verify the Urban Heat Island (UHI) trend in Perlis area. The results showed that the highest temperature is at Kangar station with the increases about 3oC on February 2015. This research is suggested a good potential in mitigation the Urban Heat Island by using Green Roof method. The sampling plot consisted of two types of green roof sampling plot which are Axonopus Compressus and Elephantopus Scaber and one roof sampling plot labeled with “Blank” as a common roof. The result showed that the indoor temperature of the three roof sampling plot indicated that the green roof sampling plot with Axonopus Compressus were lower than the Elephantopus Scaber and Blank roof sampling plot. Besides that, the indoor relative humidity of roof sampling plot Axonopus compressus also has the highest relative humidity as compared to the other two plots. Therefore, Axonopus Compressus is the best plant of vegetation to be placed as green roof. This is due to the beneficial of the characteristics and function in order to avoid the absorption of light penetration through the roof.