The use of critical raw materials in façades and the call for circularity: identifying dependencies and planning for the future

The climate crisis poses a significant threat to our planet, and the building sector plays a big role in that regard, as it is responsible for 30% of energy consumption and 27% of emissions globally [IEA, 2022]. The sector aims to reduce its impact on the environment through different strategies like transitioning to a circular economy or reducing energy consumption through the implementation of smart systems. However, these systems contain and rely on Critical Raw Materials (CRMs), which is a topic that is so far mostly discussed in regard to renewable energy technologies.The research shows a gap in knowledge, information, and awareness when it comes to critical materials concerns regarding the built environment, which is demonstrated in the example of an aluminium curtain wall façade. The analysis indicates that façades can indeed contain a high level of critical materials both in regard to the amount as well as the variety of different critical materials. From the research, it is concluded that (1) the use of critical raw materials needs to be reduced wherever possible and (2) if a reduction is not possible, materials need to be kept in the loop as long as possible.Circular strategies are therefore analysed as prospective mitigation strategies of critical materials concerns. The material policy research indicates that even though the combination of critical materials and circularity in regard to the built environment is not adequately addressed as of yet, effective policymaking could be a helpful tool in regard to the transition towards a more circular built environment and help prevent future bottlenecks in the industry. As a result, the formulated recommendations indicate how policies can address the mitigation of critical materials concerns through circular strategies.Architecture, Urbanism and Building Sciences | Building Technolog