Spatiotemporal model to quantify stocks of building structural products for a prospective circular economy

The building construction sector consumes significant quantities of resources, generates high levels of waste and creates many negative environmental impacts including carbon emissions. These problems are characteristic of linear value chains. In contrast, a circular economy approach to building construction has the potential to moderate these three problems. One way this can be achieved is to enable in-use building stocks as a repository of products for future reuse, sometimes referred to as urban mining. A key stage in such a shift is to be able to quantify stocks of construction materials and assess their direct reuse potential as products against criteria such as their location, age, type, and embodied carbon. The majority of studies of building stocks have focused on producing aggregated quantities of materials, regardless of the required information for assessing the potential value streams of future reuse. In this paper, a framework for spatiotemporal mapping of building structural products integrating external geometries and construction history is presented. To demonstrate its capacity, the stocks of clay bricks within the external walls of buildings are assessed where six types of buildings and four types of bricks are specified. Dimensions, weights, ages and embodied carbon of materials are estimated for case studies of three urban regions in Northern England: Manchester, Leeds and Bradford, and the results are spatially mapped for the city of Bradford. The paper provides the first systematic and comprehensive area-wide model to evaluate stocks of building structural products for future urban mining and circular economy of building construction systems.