When means and ends meet: examining strategies and carbon accounting fit for Our Global Future

Global efforts to accelerate the transition towards whole-life carbon (WLC) neutral buildings are key to ensuring humanity’s survival in a world beaten by climate change. WLC design is expected to optimize embodied and operational GHG emissions, and corresponding estimates imply that both types are explicitly accounted for. As varied carbon accounting approaches have been used, this paper overviews two promising strategies for carbon removal - biobased materials and mineral carbonation - and discusses the implications of the main calculation approaches applied to them. Crushed concrete carbonation and CO2 curing can uptake almost 10% of the original emissions each, at low additional cost. Still, both assume continued use of concrete, which has high embodied emissions. Well-established in temperate climates, biobased construction materials are not mainstream and durability challenges in certain exposure conditions prevent their unrestricted contribution as carbon sinks. As to calculation rules, assigning emissions and uptake to the life cycle stage in which they occur can be tricky when recycling, reuse and waste management activities are inherently involved. By design-reduction and compensation measures must be sought for and - if we are to reach Our Global Future - partnerships and resources urgently directed to all nations to play their part in the collective decarbonization.