Determining the environmental potential of demountable building elements

Demountable building is put forward by different policies 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 in practice. To stimulate building actors to (correctly) implement demountable building elements, it is imperative to be able to quantify their potential environmental benefits and determine under which conditions these benefits can be achieved. Life cycle assessment (LCA) allows to quantify the environmental impact of a product, building element or building over its whole life cycle. It is identified as an important tool to measure the environmental 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 their different possible use scenarios. This allows to determine for which scenarios (i.e., under which conditions) demountable building elements are environmentally beneficial. However, 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 research 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. This is illustrated by conducting an LCA with variable influential parameters for a demountable and non-demountable space dividing wall. According to a traditional, 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. These types of LCAs can be used to set achievable targets regarding demountable building.