Evaluating sustainable building strategies: Life cycle comparison of demountable and conventional built-environment structures

Abstract

This study investigated the environmental sustainability performance and implications of two different types of building structures: Lego-like demountable and conventional building structures and this assessment encompassed both novel geopolymer-based concrete and ordinary Portland cement-based concrete materials. In the scope of this study, the environmental impact of novel construction and demolition waste (CDW)-based materials and demountable structures was quantified. Environmental implications of novel CDW-based material were unveiled through a comparison between the novel CDW-based geopolymer concrete and traditional cement-based concrete. A comparative analysis was also conducted between demountable and conventional construction systems to identify the hot spot of the developed demountable system process. The study involved modelling and analyzing the production and manufacturing processes through the utilization of the Life Cycle Assessment (LCA) tool. The results indicated that the demountable structure using cement-based concrete had more significant environmental implications compared to its counterpart using an equivalent volume of geopolymer concrete. The environmental impact of the building constructed using the fully demountable system was higher than that of the building constructed using the conventional system. However, cyclic use led to undeniable reductions in the overall environmental impact of demountable system. The steel necessary for the fully demountable systems emerged as a significant hotspot, contributing to substantial environmental impacts in all scenarios, primarily due to its energy-intensive production process.