Building Life Cycle Carbo Emissions: A Review

Abstract

Buildings are responsible for a substantial percentage of energy use related carbon emissions that contribute to global warming. Examination of buildings’ carbon emission has been one of the key issues for the sustainability. As a high-density city, Hong Kong has increasingly advocated the use of prefabrication for high-rise residential buildings. However, although life cycle carbon emission assessment has been widely applied to buildings, its implications on high-rise prefabricated buildings remain unclear. Therefore, this paper aims to contribute to a better understanding of the life cycle carbon emission assessment of high-rise prefabricated buildings in Hong Kong. The review was carried out through a meta-analysis of relevant previous studies and a more focused examination of research in the context of Hong Kong. The meta-analysis was conducted from the temporal, spatial, functional and methodological dimensions using seven variables, namely, life span, life cycle phase, research area, research scope, building type, building height, and life cycle assessment method. The focused examination reveals a severe gap in knowledge of the life cycle carbon emissions of high-rise prefabricated buildings in Hong Kong. A lack of understanding was also identified of the operational stage and indirect implications of prefabricated buildings. Furthermore, there is absence of consistent life cycle carbon assessment method in addressing the gaps. A systemic model of examining the carbon emissions of high-rise buildings is suggested to address the full building life cycle.