Life cycle assessment of demountable building elements: Influential design and use parameters

Demountable building is put forward as a solution to reduce the environmental impact of the construction sector. However, uncertainty on the actual environmental benefits that can be achieved, hinders its implementation. Life cycle assessment (LCA) can be used to measure the potential of demountable building. Variable design and use parameters, such as the number of use cycles and material lifespan, should be incorporated in LCAs of demountable building elements to account for different possible use scenarios. Existing LCAs of demountable elements only vary one parameter at a time and/or consider simple reuse scenarios and building elements. The aim of this paper is to show how LCAs of demountable building elements can be organized by focusing on influential design and use parameters, while resolving the limitations from existing research. The influence of the parameters is determined through a two-step sensitivity analysis executed for two types of building elements: space dividing walls and facade systems. First, parameters with a low influence are omitted through a screening sensitivity analysis. Then, the Sobol' indices of the remaining parameters are calculated. The results show the influential parameters are the same for both types of building elements. Finally, an LCA with variable influential parameters for a demountable and non-demountable space dividing wall is conducted. According to a non -variable LCA, the non-demountable wall has the lowest environmental impact, but when considering variable parameters, the use scenarios for which the demountable wall has the lowest impact become clear, for example, when the wall is relocated every five years.

Automated summary

This study explores the potential of demountable buildings in reducing environmental impact through life cycle assessment. By conducting sensitivity analysis on influential design and use parameters, the study identifies the extent to which different building elements contribute to environmental impact. The results show that demountable buildings can effectively reduce environmental impact through proper design and use.