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Abstract

Cement is an essential building material but producing it generates 7%–8% of global CO2 emissions. Two thirds of these emissions are process-related and cannot be eliminated by switching to clean energy sources. Meeting the Paris agreement’s call for ‘highest possible mitigation ambition’ requires faithful assessment of all mitigation options, including demand-side measures to reduce cement emissions. To assess how political actors define and justify their highest possible ambitions for the housing sector, we analyze cement decarbonization roadmaps in Germany, the Netherlands, and Norway: industrialized countries selected for their high floorspace per capita. We identified 30 decarbonization measures using qualitative document analysis. We coded the measures iteratively from roadmaps and literature and categorized them into a cement-specific mitigation hierarchy (avoid, reduce, reuse, substitute, minimize, ‘Capture, Store and Recarbonate’) that integrates supply-side decarbonization with demand-side sufficiency in housing. Our findings expose a persistent sufficiency gap: roadmaps prioritize incremental technical solutions and speculative carbon storage, while neglecting transformative measures that reduce overconsumption like separating spacious living units, building smaller or reducing housing overconsumption. This inflates cement demand, the need for carbon capture and storage as well as associated residual emissions. We conclude that current mitigation ambitions are not the highest possible but, instead, politically constructed versions that sideline demand-side sufficiency measures. Truly Paris-aligned pathways must first adopt a sectoral perspective to reduce cement emissions and then also integrate demand-side strategies through transdisciplinary collaboration, ensuring a faithful assessment of all mitigation options.