Reconfiguration of Practices towards a Circular Economy in the Architecture, Engineering, and Construction sector: Change throughout a Persistent System

The Architecture, Engineering, and Construction (AEC) sector is a major contributor to CO₂
emissions and resource consumption. In response, the Netherlands aims to make the sector 50% circular by 2030 and fully circular by 2050. However, the transition from a linear to a circular economy is complex due to technical, organisational, and cultural barriers. This dissertation explores how interorganisational behaviour and routinised practices within and beyond construction projects influence the realisation of circular ambitions. This research highlights the importance of top-down support, equal partnerships, shared goals, and intrinsically motivated individuals in construction projects. Trust, transparency, flexibility, and a shared team identity further foster the redefinition of traditional roles so as to drive innovation. However, factors such as focus on short-term cost and risk aversion often hinder progress. The dissertation further combines Sustainability Transitions Research (STR) and Social Practice Theory (SPT) into crossover frameworks that capture both systemic change and everyday practices. These are used to analyse (mis)alignments in the system-of-practices around construction projects. It was found that using secondary materials often clashes with notions of quality, safety, and aesthetics. Increasingly, Circular Building Hubs (CBHs) are brought forward as answer to this problem. This research shows that these hubs can be accelerators in the transition, though they are seen as temporary rather than permanent solutions. Ultimately, no single intervention will enable the shift to circularity. Instead, multiple coordinated changes in practices are needed. This dissertation provides tools for researchers and practitioners to navigate this complexity and encourages learning, experimentation, and a systemic approach to support sector-wide transitioning.