Life cycle environmental benefits of a forward-thinking design phase for buildings: the case study of a temporary pavilion built for an international exhibition

The life cycle of a pavilion built for an international exhibition was investigated to understand the role that the design phase may play in the environmental sustainability of buildings. The limited life span of the structure allowed for a complete life cycle assessment (LCA) based on primary data to be undertaken, including the end of the first life. A methodology that considered an extension of the service life was applied to estimate the environmental impacts of distinct end-of-life scenarios. Results confirmed the paramount importance of the design phase in improving the life cycle sustainability of buildings. Accurate selection of materials allowed to markedly reduce the impact of the product stage (e.g. 37% fewer greenhouse gas emissions). Design for disassembly proved to be a necessary but not a sufficient condition to minimise the end-of-life impacts: design phase should not be limited to the appropriate selection of materials and components’ connections but must also foresee a second use for the structure or the materials at the end of the first life. Forecasting an after-life for the structure could reduce the life cycle burden up to 40% for several environmental impact categories. Conversely, if the second use is not predefined, the economic cost in the dismantling operation could become the priority rather than the salvaging of the components. Results of the present study may be used by future (temporary) building designers to improve the sustainability of their structure and to avoid the errors identified in the present case.