Where if? Using spatial, building-stock-driven simulations to explore construction circularity strategies in Gothenburg, Sweden

Journal article, 2026

Recycling construction materials can significantly reduce the environmental impact of the construction and demolition sector. However, implementing circularity strategies requires a spatially refined understanding of material stock dynamics. This study introduces a stock-driven and rule-based simulation that forecasts – over space and time – material stocks, flows, and associated embodied carbon resulting from construction, renovation, and demolition activities. It enables the exploration of how urban parameters, such as the recycled content of new constructions, demolition rates, renovation rates, and different types of new construction, influence material flows and embodied carbon. Using Gothenburg's residential building stock, the simulation's capabilities are demonstrated by tracking eight building materials along with their embodied carbon over time, across the parameters, and for two scenarios: a baseline, and a policy on energy efficiency. Results show that prioritizing renovation over demolition consistently reduces embodied carbon impacts, while increasing material circulation further enhances these benefits. Additionally, aligning new housing typologies with the composition of materials released from demolitions improves resource efficiency, although in the Gothenburg case, varying the share of single- versus multi-family housing has limited influence on overall outcomes. The primary contribution of this study is the model developed for evaluating the interactions between demolition, renovation, and material circulation in a spatially and temporally explicit manner. The model provides urban planners with actionable insights into the spatiotemporal dynamics of material supply, supporting more informed strategies for transitioning toward a sustainable and circular construction sector.