This paper presents the findings of an interdisciplinary academic exchange exploring the transition towards a circular built environment (CBE), developed over two years of collaborative work at Delft University of Technology’s Circular Built Environment Hub. A key outcome of this work is developing a comprehensive definition of the CBE and the related Scales to Aspects model, which connects the multi-scalar and cross-disciplinary nature of circularity, ranging from materials and components to buildings, neighbourhoods, cities, and regions. It highlights critical tensions, such as the lack of integration between circular strategies and other global challenges.

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.

Strategic programmes are frequently employed by organisations to drive transformational change, particularly when sectors pursue systemic shifts, such as the circularity transition. However, despite their potential, these programmes often fail to effect lasting change within their parent organisations, with outcomes remaining disconnected. This study examines how programme integration mechanisms shape organisational transformation in circularity-oriented change programmes. Several mechanisms were identified through a comparative case study of Dutch public construction clients. The findings suggest that isolating such programmes from the parent organisation hinders organisational transformation. Instead, the early incorporation of integration mechanisms is essential to facilitate both learning and unlearning processes, ensuring the effective and sustainable adoption of circular practices. Moreover, findings show that temporal alignment emerges as a decisive factor in a programme’s transformative capacity, as mismatches between programme and organisational learning trajectories can limit systemic impact. These insights contribute to strategic programme literature by demonstrating how these programmes can, depending on their formal and informal mechanisms, promote or stall transformative change.

The architecture, engineering, and construction (AEC) sector is in need of a transition towards a circular economy. This article offers an analysis of two cases with a wide variation regarding project dynamics in the Netherlands. Alignments and misalignments were analyzed between practices concerning seven design strategies for circular design based on social practice theory and concepts from the multi-level perspective. Results show that many misalignments still hinder the transition, mostly concerning the use of secondary resources, such as notions regarding quality, beauty, and safety among project team members or rapid decision-making processes of the municipality that misalign with the uptake of design with secondary resources. This article offers directions for reconfiguration, such as better tuning between project planning and urban planning and taking up a more flexible stance regarding the function of the building. This research is interesting for practitioners and researchers focusing on the transition towards a circular economy in the AEC sector.

Despite growing government and market interest to use Circular Building Hubs for reusing construction components, few academic articles have been written about them. We know little about the potential of hubs to answer to the challenges of reuse in the present and future, and their potential to drive systemic changes towards a circular economy. Using various qualitative research methods, this article aims to respond to this research gap by applying social practice theory and the multilevel perspective on past and future practice reconfigurations within the system-of-practices in which these hubs reside. Results show that within hubs reconfiguration from demolition to deconstruction and repair and refurbishment practices have been developed. However, selling components remains challenging, and procurement for reuse and design skill remain underdeveloped. Practitioners expect the system-of-practices to professionalize in the coming years, resulting in market growth for secondary components. Long term, practitioners expect hubs to shrink or disappear because the balance between supply and demand will be controlled digitally. Hubs are therefore a driver for the transition, but only as intermediate step, not as solution for a circular economy. This article is particularly interesting for academics studying CE and transitions, and policy makers interested in developing Circular Building Hubs.

Researchers employ many different approaches to study transitions towards more sustainable futures, of which Sustainability Transitions Research and Social Practice Theory are often used. These approaches offer complementary concepts that are helpful to analyse, explain, forecast, and drive sustainability transitions, e.g. heuristics on changing institutions (Sustainability Transitions Research) or dynamics to change behaviour through practice development (Social Practice Theory). However, despite first attempts, it remains unclear how the approaches can be used together. Therefore, the aim of this paper is to expose crossover frameworks in which these approaches are used together, elaborating on conditions that make this possible, and the strengths and weaknesses of specific crossover frameworks. A systematic literature review has been conducted, investigating the potentials and the limitations for crossovers between Social Practice Theory and Sustainability Transitions Research by analysing the approaches according to the different ontologies and theories and then analysing frameworks that have been created so far. This research elaborates on six crossover frameworks that have been created that all have diverse strengths, such as the ability to conceptualize early transitional changes or finding points of resistance in transitions. All the found crossover frameworks made use of either the multilevel perspective or transition management. Other frameworks of transition research have not been found. This research shows that there has been surprisingly little research to crossover frameworks that incorporate an element of time. The exposition following from this study is interesting for researchers and policymakers working on sustainability transitions and sets an agenda for further framework development.

The aim of this paper is to better understand the dynamics of circular construction projects and how these interorganizational projects contribute to the transition towards a circular economy. It is essential that the construction sector develops and adopts interorganizational initiatives to support the transition to a circular and low-carbon construction economy. A benefit of being involved in such initiatives is that organizations reflect on the emergence and acceptance of new practices related to changing organizational roles and responsibilities. In this paper, we study eight circular construction projects within the context of an interorganizational initiative to stimulate the transition towards a circular economy by exploring insights from evaluations thereof. We build upon literature from Sustainability Transitions Research (STR), circular construction research, and interorganizational project studies. Our findings show three clusters of dynamics that are relevant in the realization of circular ambitions in interorganizational construction projects: (1) prerequisites, (2) temporal dynamics in interorganizational projects, and (3) contextual influences. These insights highlight factors that enable the realization of circular ambitions in construction projects and contribute to our understanding of the dynamics of interorganizational construction projects and their role in the context of STR.