Green roof maintenance for non-residential buildings in tropical climate: case study of Kuala Lumpur

The implementation of a green roof is best suited for urban areas, as it provides an array of environmental benefits toward mitigating and adapting to climate change, including reduced flood risk, greenhouse gas emissions, urban heat island effects, and air pollution. However, green roof research and maintenance awareness in Malaysia are comparatively scarce, largely due to the absence of local tropical green roof guidelines. Therefore, this paper aims to explore current green roof maintenance practices and challenges for non-residential buildings in Malaysia through case studies and in-depth interviews. These results were then compared with three international green roof guidelines, namely those of the Royal Institution of Chartered Surveyor, Singapore’s National Parks Board, and the US Environmental Protection Agency. The findings show that current green roof maintenance elements implemented in the case studies are insufficient and inadequate for Malaysia’s tropical climate conditions. The paper recommends nine (9) green roof maintenance elements specific for non-residential buildings in Malaysia and the tropical climate: plant selection, rainwater harvesting system, pest control, monitoring performance, accessibility, irrigation cleaning, waterproofing membrane maintenance, plants and growing medium, and maintenance of outdoor furniture. As this paper has only included data from Kuala Lumpur, this limits the generalizability of the findings to other buildings in Malaysia and a tropical climate. The implications of this study may provide further direction for researchers to consider a larger sample size and other cities in a tropical climate. This study will allow policymakers and building stakeholders to develop suitable green roof maintenance guidelines.