Measuring Building Circularity Through Materials and Connections: An Evaluation Framework for Architecture Integrating Reused, Bio-Based and Recycled Components

In line with circular bioeconomy goals, the reported research focuses on circular building materials, intended as reused components, recycled and bio-based materials, including those derived from sub-products and waste, as a strategic solution to simultaneously cut embodied and operational carbon emissions in buildings. In particular, the research aims to provide a methodology for an early, rapid and effective assessment of the contribution that circular materials can give to reducing climate-altering emissions and resource consumption. The research started with the collection, selection and analysis of multiple case studies of buildings using circular materials and adopting different circular design strategies. The paper reports in particular the mapping of circular design strategies and materials in ten case studies, representing different approaches. Moreover, by collecting and comparing fifteen existing frameworks of indicators for circularity evaluation at the building and product level, selecting relevant indicators and integrating specific ones, the research develops a set of eight KPIS, a specific evaluation framework that allows to assess the effects of alternative combinations of materials reused, bio-based and recycled building materials. The KPIs set was tested on a selection of three relevant case studies of buildings using circular materials, to verify the effectiveness of the indicators in supporting the designer in taking material related choices.