Absolute sustainability assessment of the Danish building sector through prospective LCA

Abstract

This study examines how a combination of prospective life cycle assessment (pLCA) and absolute environmental sustainability assessment (AESA) can support shaping environmental strategies in the building sector. The paper highlights the benefits of pLCA as a forward-looking approach that integrates technological and socio-economic scenario projections. Through a case study of the Danish building sector, it investigates the potential of technological advancements to meet absolute sustainability targets and explores mitigation strategies to bridge the gap between current impacts and absolute targets. The study covers 16 environmental impact categories.

The study identifies which building materials have the strongest potential to mitigate climate impacts and reveals risks of burden shifts towards other impact categories. By modelling future construction in Denmark (2025–2050), the study finds a significant divergence from current consumption patterns and exceedance of the planetary boundaries suggesting that technological advancements cannot alone take construction in Denmark towards sustainable practices. The study therefore suggests a shift towards biobased materials and reduced construction activity as viable mitigation strategies. The study highlights a trade-off between climate change and land use when conventional building materials (concrete, steel etc.) are replaced by biobased materials. Moreover, the study shows that anticipated changes in the background system rely on solutions that will increase some environmental impacts e.g. land use and resource use of metals and minerals. Overall, the findings underline the importance of adjusting current LCA methods to ensure relevant assessments that can support decision making for achieving rapid climate mitigation as expressed by the IPCC and ensure that burdens are not shifted unintentionally.