ACT-FLOW Framework: A Multi-Level Approach to Enabling Local Territorial Circular Processes in the Construction Sector Through Actor Networks and Material Flows

The transition towards circular practices in the construction sector requires integrated approaches addressing both material resource procurement and the fragmentation of local stakeholder networks. This study presents the ACT-FLOW Framework, a multi-level approach enabling territorial circular processes by integrating actor networks and material flows. The framework comprises three interconnected levels (strategies, processes, and indicators) supporting the definition, implementation, and evaluation of circular practices across building and territorial scales with an iterative refinement phase. Methodologically, it was developed through a Design Science Research approach (DSR) articulated into four steps: (1) define the scope and boundaries; (2) develop a knowledge base; (3) structure the framework and its components; and (4) validate and apply it to a real case, the Circular Design Polito Lab, a research infrastructure currently under development by the Politecnico di Torino (Italy). The results demonstrate how the framework supports stakeholder coordination, structures circular workflows, and enhances circular performance monitoring. The primary limitation is that the case study has not yet been realized; consequently, it is not feasible to conduct an ex post but only an ex ante evaluation of the results. Future research will assess the framework’s capacity to foster ecosystemic conditions for circular construction practices through its longitudinal application across project phases.