Adaptive reuse of buildings and life cycle environmental and economic benefits of such strategies

It is common for school buildings in Singapore to undergo major renovations or even demolitions after less than 30 years of service. Reasons for such major but premature renovations or demolitions, which typically generate... [ view full abstract ]

It is common for school buildings in Singapore to undergo major renovations or even demolitions after less than 30 years of service. Reasons for such major but premature renovations or demolitions, which typically generate large amounts of construction and demolition (C&D) wastes, include expansion or changes in educational curricula, increase in student and staff populations, and improvement in facilities.

The objective of this study is to identify patterns in the past renovations or demolitions of 15 school buildings and propose a coherent set of design guidelines that create alternate designs for these (and future) schools that can reduce the need or extent of future renovations and demolitions. The life cycle environmental and economic benefits of these designs that promote reuse will also be calculated.

Firstly, each of these 15 school buildings was evaluated in terms of four key factors: 1) internal adaptability, 2) use adaptability, 3) extension adaptability, and 4) planning and prospective adaptability.

Internal adaptability refers to modifications that are done in the existing layout of the building. Extension adaptability refers to the state in which physical elements, such as an extra floor, is added to an existing structure so as to allow the building to adapt to new demands. Use adaptability refers to the ability of a space to be used for alternate uses without any or much renovations. Planning adaptability is the measure of flexibility of the whole planning process in response to any change that may occur during the construction work, or make up for the loss time and construction hitches that may delay the work. Prospective adaptability means the measures that are included in the project to guarantee future flexibility, after the completion of the building.

For the renovation or demolition works performed on each building, the amount of cost, time and effort required were quantified and scored. Patterns in these renovation and demolition projects, and the buildings' scores, were then identified. These patterns led to a coherent set of design guidelines that create alternate designs for these (and future) schools toreduce the need or extent of future renovations and demolitions.

For each of these alternate designs, the potential net amount of C&D wastes that could be saved and net decrease in life cycle impacts (such as including global warming potential, humantoxicity potential and acidification potential) and resource requirements (suchas energy, water and fuels) were estimated.

Finally, for each of these designs, the potential of each kind of generated C&D wastes for recycling or reuse, and the life cycle costs of the buildings were estimated. In cases whereby such reuse or recycling are possible, the net reductions in the aforementioned life cycle impacts, resource requirements and life cycle cost were re-calculated.

Based on the above results, policy strategies were recommended to promote and incentivize this alternate design approach inSingapore. The international relevance of this alternate design approach will also be discussed.