Mohit Arora
Engineering Product Development Pillar, Singapore University of Technology and Design
Mohit is pursuing PhD at Engineering Product Development Pillar of Singapore University of Technology and Design. His doctoral thesis focuses on identifying barriers for material reuse in cities and creating support tools for reuse of building components in resource constrained urban systems. He has previously been trained in Environment Engineering at Indian Institute of Technology Bombay. He is passionate about applying Urban Metabolism, Material Reuse and Resources Efficiency principles for greater benefits of scientific community and society.
With the threat of global warming and over-exploitation of natural resources, the reuse of secondary resources has become increasingly crucial for a sustainable world. The building sector is known to be responsible for significant resource consumption and greenhouse gas emissions, emphasizing the need of policy efforts to be directed towards minimising the overall resource burden of the built environment (UNEP, 2012; EU and Copenhagen Research Institute, 2014). Many efforts have been directed towards developing energy-efficient buildings. However, the potential for urban mining and resultant secondary resource utilisation remains unexplored. Past efforts include limited examples of aesthetic-driven material salvation, or the reuse of antique buildings features (Bill Addis, 2006; Allwood and Cullen, 2012). The systemic reuse of building components remains far from reality.
This study aims to estimate the potential for urban mining in Singapore’s dense built environment and analyses critical factors affecting the reuse of resources with a focus on building component reuse. Examples of building components that can be reused include structural components like beams, columns, steel frames and building interiors like doors, window, frames, kitchen and toilet fixtures, partitions, lighting, furniture etc. For a market-driven circular economy, this study also proposes a business model and its evaluation criteria for firms to tap on secondary resources.
Singapore has one of the highest cement consumption per capita, where the construction sector’s contribution to GDP has doubled in the last decade (BCA Singapore; Gursel and Ostertag, 2016). Urban redevelopment and land scarcity remain major reasons for land use changes and early building obsolescence. For an import-dependent country like Singapore, urban mining offers a potential for greater material efficiency. While the existing building stock can become a significant source of materials, accurate estimations of recoverable and reusable components and materials remain yet unavailable.
This study first quantifies recoverable and reusable building components at the end-of-life buildings in Singapore, for secondary applications. Using available data from regulatory bodies, we account for the existing building stock and yearly building demolition to estimate an inventory of recoverable building components.
The demolition case study highlights lack of a reuse market, shorter time for demolition, lack of quality criteria and poor information on secondary resources as the primary bottlenecks for building component reuse. We finally argue that the circular economy an indeed be realized in the building sector through urban mining and social entrepreneurship.
• Sustainable business models , • Sustainable urban systems , • Circular economy
