Optimized early-stage life cycle assessment of buildings -Developing a tool enabling early-stage parametric life cycle assessment

Abstract

In the early stages of a building project, there is low quantity and quality of data regarding building materials while the ability to influence the environmental impact is high. Easy ways of assessing environmental impact of materials in these stages can make a big difference and shift buildings’ contribution to global warming towards a more sustainable track. The aim of the thesis project was to develop a parametric tool enabling earlystage Life Cycle Assessment (LCA) of buildings. The tool focus at guiding the user in lowering the embodied carbon from buildings by assessing building materials and building shapes. The tool also seeks to be educational about the climate impact from the production phase of buildings, and the intended user group is architects. The method of the thesis followed three steps:  requirement definitions based on interviews and a tool and literature review  tool development  case studies for validation The interviews were a crucial step to inform the later tool development and to make sure the tool is usable by the intended target group. From the interviews it was found that important features of an early-stage LCA tool are to use national, generic data, show the results in a visual way and make it fast and easy to use. Additional results from the interviews are identified industry needs and challenges. The case studies included user tests and numerical tests. The developed tool fills most criteria set by the interviewees; however, further validation of the loadbearing concepts is asked for. The tool manages to balance a high level of detail and a user-friendly interface, and the calculated results are within a 15% accuracy. The thesis project shows that the integration of the users' needs and expectations from the very beginning of the development of assessment tools will ensure the tools’ applicability in the design process.