Investigating circularity in the construction and demolition sector through remote sensing: A case study of Bolzano/Bozen, Italy

The built environment in urban areas contributes significantly to global waste generation through construction and demolition activities, highlighting the need for circular economy strategies to ensure sustainable development. Digital technologies offer fast and reliable methods to track material flows and improve resource efficiency. This study proposes a novel approach that integrates data from OpenStreetMap (OSM) and the Urban Atlas for land-use identification. The material stock (MS) is estimated via a geographic information system (GIS) to analyse the spatial characteristics of buildings, combined with material intensity (MI) data to assess the mass of materials within structures. Together with the quantification of material stock, hotspots of construction materials within the building stock are identified. When applied to the case study of Bolzano/Bozen, Italy, this approach estimated 130 tonnes per capita of accumulated building stock in the city and 40 tonnes per capita of material stock in infrastructure networks. This remote sensing methodology provides detailed insights into the quantity and distribution of materials in buildings and networks. The openness and availability of OSM data, as well as their independence from cadastral records, make this approach particularly advantageous for obtaining input data for the life cycle assessment (LCA) of buildings and the development of waste management strategies.