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Abstract Purpose The “ avoid-shift-improve ” strategy framework was developed by the United Nations Environment Programme (UNEP) to foster material decarbonisation in the building and construction sector. This study applies the framework to use of Eccentric Braced Frames (EBF) in buildings structures, assessing how structural design and material choices affect whole-of-life climate change impacts. We identify the relevance of specific Life Cycle Assessment (LCA) methodological choices on the results, and the implications for supporting informed decision-making during the building design stage. Methods Five steel EBF structures were modelled which differ according to their source of raw materials (primary steel or reconditioned/reused steel), design for disassembly (DfD) features (bolted or welded), and end-of-life (EOL) management (recycling, reusing and/or landfilling). The climate change impacts were assessed based on two main scenarios: no seismic activity and one anticipated seismic activity during the 50 years reference service life (RSL). Additionally, sensitivity analyses were conducted to account for modelling assumptions and prospective technologies. The study was performed using both static and dynamic LCA methods to address the temporal dynamics associated with these EBF structures, focusing on the climate change impacts over 150 years from the construction year. Results and discussion Using static LCA, the results show that using reconditioned/reused steel for constructing EBF structures significantly reduces the climate change impacts compared with use of primary steel. The climate change impacts are higher in the seismic scenario compared to the no seismic activity scenario for all the structures, mainly due to the additional demolition and reconstruction activities. As expected, the reuse strategies have lower climate change impacts than recycling and landfilling at the EOL stage (although the ranking may change depending upon the chosen allocation method). The dynamic LCA (dLCA) results additionally show the contribution to radiative forcing over time associated with greenhouse gas (GHG) emissions (measured in Wm − 2 ), and how prospective technological advances in steel manufacturing and recycling can influence the climate change impacts over time. Conclusions The study highlights the importance of: (i) reusing now rather than in the future to “ avoid” the climate change impacts associated with primary steel manufacture, and to “ improve” CE practices in the building and construction sector to align with the “ avoid-shift-improve ” framework; and (ii) use of static LCA complemented by dynamic LCA for robust climate change assessment in order to provide deeper insights into the longer-term influence of design-stage decisions when assessing products with extended lifespans (such as buildings).
Weerasinghe et al. (Mon,) studied this question.