INCORPORATING GREEN ROOFS ON EXISTING HDB RESIDENTIAL BUILDINGS

Abstract

Many countries including Singapore have adopted green roofs in the built environment to mitigate the Urban Heat Island phenomenon. Although roof gardens have been installed in various private commercial and residential developments here, its provision in public housing is still considerably limited to mainly multi-storey carparks and new housing developments. As of present, there have been no official plans by local authorities to incorporate green roofs on existing Housing Development Board (HDB) blocks and examples of retrofitted buildings are not so prevalent here. This highlights the reality ofwasted roof spaces which could be utilized and transformed into a green roof which can provide numerous benefits. Thus, this dissertation aims to propose the incorporation of green roofs in existing HDB residential buildings by employing exploratory and descriptive research techniques. The Multnomah County Building in Portland and the Montgomery Park Business Centre in Baltimore were chosen as case studies portraying examples of successful green roof retrofit projects. The case studies provide valuable insights, knowledge and lessons which can be gained and applied to the local context. Analyses of the case studies found that both projects adopted extensive green roof systems and are motivated by environmental benefits, possible roof longevity and aesthetic reasons. Also, both cases demonstrate that all perceived barriers of green roof retrofit developments can be overcome. The availability of field expertise, support from the community and local authorities and the cooperation between the involved parties are key factors determining the success of the project. By applying the findings from the analyses to Singapore s context, it can be deduced that extensive green roof systems are viable options for retrofitting existing HDB residential buildings as they are lightweight, low-maintenance, less expensive to install and offer numerous benefits. Nevertheless, there is a need to educate the community and developers regarding the technical aspects and advantages of green roofs in order to create higher awareness and gain support, inevitably leading to the increasing trend in green roof development.