Life-Cycle Assessment as a decision-support tool for early phases of urban planning: evaluating applicability through a comparative approach

Katarina Slavkovic, postdoctoral researcher at the Building2050 Group, presents a paper prepared for the Sustainable Built Environment SBE 2019 conference in Graz. The objective of the study is to assess the ability of life-cycle assessment (LCA) - based tools to support the decision-making process for urban-level projects. Three tested tools, developed for the Swiss built environment context, include SETUP, which stands for Specific Environmentally-conscious Targets for Urban Planning, Smeo Red thread for sustainable construction, and Tool for 2000-Watt-Society-sites.

While ambitious environmental objectives are being set for new constructions in Switzerland, the assessment of urban-scale projects and comparison of their performance to national targets are made possible by a growing number of life-cycle assessment (LCA) tools. However, previous research emphasizes the lack of existing tools to support the decision-making process at the early design stage, characterized by a low level of project details.

This paper presents a comparison between three LCA tools. The first, stemming from a research and development project (SETUP), is an exploration tool relying on a database of urban-level scenarios and their environmental performance, able to convert district targets (e.g. 2000-Watt society objectives) into specific sub-targets at the building or component levels. The other two are online LCA tools currently available to practitioners (Sméo and Calculation tool for 2000-Watt-society-sites), that allow assessing the project and verifying its compliance with a given target.

Each tool was applied to a low-carbon case study, the blueFACTORY district in Fribourg, in two hypothetical contexts corresponding to the schematic and detailed project development phases, characterized by different levels of details. When used for the assessment of a project at a more advanced development stage with a high resolution of detail, findings indicate that all three provide similar environmental performance results. However, in early planning stages, SETUP shows better abilities to support decision-making by providing ranges of results and highlighting uncertainties and the influence of design parameters that have not yet been fixed.

The smart living lunches take place once a month from 11 am to 1 pm in Fribourg to present the research activities of the Smart Living Lab. A lunch is served after the presentation. These events are designed for the Smart Living Lab’s community.