Green roof as a technology towards sustainability: A perspective of benefits offered

Abstract

Green roof is a building envelop embedded concept to compensate the consequences of green losses due to building constructions with its numerous benefits in all environmental, economic and social aspects. But the application of green roofs in Sri Lankan buildings is seemed to be limited due to the deficiency in comprehensive awareness of the benefits of the green roof concept among construction stakeholders. Though the global studies on green roof application are widespread among different green roof types, their results do not indicate any consistency between green roof application and climate. This warrants the current study to investigate the benefits offered by green roofs in the local context. A thorough literature synthesis had initially conducted to review the green roof concept, types of green roofs, and benefits offered. Subsequently, a preliminary investigation was performed to identify the green roofs available in Sri Lanka. Thereafter, the case study strategy was adopted to evaluate the benefits of intensive and semi-intensive green roof types through interviews. The collected data were analysed using manual content analysis. Analysis revealed that both intensive and semi-intensive type offers key benefits such as energy conservation, and stormwater run-off reduction in the Sri Lankan context. In addition, the intensive type offers benefits such as carbon emission control, and absorption of urbanized noise which can be aligned with the main criteria of sustainable sites, energy & atmosphere, and indoor environment quality of green rating systems. Therefore, the study suggests that an adequate recognition to green roof implementation in the green rating systems would enhance the green roof application and thereby contribute to achieving sustainability of buildings in terms of these criteria.