As discussions around the circular economy (CE) start to move beyond Eurocentric approaches, US stakeholders are left with the mission of carving their way into CE. The US building sector has substantial impacts in resource use, waste generation, and carbon emissions, and a long way to go on the path toward CE. Circular building design involves strategies such as design for disassembly (DfD) to allow future repair, remanufacture, and reuse of building components, building adaptive reuse, and using salvaged materials in new construction. Although strategies like DfD have been discussed for the last 2 decades, they have failed to gain traction in building design. However, there is a limited body of literature devoted to understanding the barriers and enablers for key circular building design strategies like DfD. A few recent empirical studies in European countries have identified barriers for circular building design, which in this study were categorized according to their nature (regulatory, economic, technical, educational, cultural, technological, and environmental barriers). However, given the different regulatory, economic, and cultural contexts in which the US is situated when compared with European countries, the barriers identified in prior studies and their respective enablers may not apply to the US. For example, contrary to European countries, the US is yet to create a national CE-specific legislation or action plan. Thus, bottom-up efforts from industry stakeholders are key to achieve progress toward CE in the US. Yet there are no studies that investigated barriers and enablers to circular building design in the US context. This study aims to fill this knowledge gap. The authors interviewed architects across the US to understand the perceived and experienced barriers to circular building design in the US building sector and propose enablers to overcome these barriers. The barriers differed in nature from those found in European countries: although the share of technical and economic barriers were similar, more educational and cultural barriers were found in the US, as opposed to a larger shares of regulatory and technological barriers in European countries. The authors discuss the most mentioned barriers in the US (e.g., cost and schedule constraints, lack of clarity on what CE entails, and existing regulations and codes hinder reuse and repair), and the barriers that were new to the literature (e.g., belief that DfD compromises building durability and resiliency, conflicting goals between pre-engineered structures and future reuse, and the widespread use of nondurable building components). Finally, the authors propose enablers to address each barrier and discuss the role of different stakeholders in implementing enablers. Policymakers, non-governmental organizations (NGOs), industry associations, and researchers were the stakeholders with the highest leverage to enable CE in the US building sector.

The circular economy implementation in the built environment is hindered by the complexity of CE strategies and unique nature of the construction industry. Digital technologies have been explored as promising solutions to aid decision making and enable circular solutions in the architecture, engineering, and construction sector. The literature on both circular economy and digital technology fields has grown exponentially in the past few years, and there is a need for a comprehensive review of the state-of-the-art applications, integrations, potential, and limitations of digital technologies in the circular economy context. Through a systematic literature review, this study identified ten key digital technologies to enable circularity in the building sector: building information modeling, spatial data acquisition, artificial intelligence and machine learning, Internet of Things, blockchain, digital twin, augmented and virtual realities, digital platform/marketplace, material passports, and additive manufacturing and digital fabrication. In this study, we review current applications, discuss their integrations, match digital technology opportunities with circular economy barriers, and map the digital technologies applications along a building’s lifecycle. Blockchain and material passport technologies demonstrated potential to enable circular economy strategies throughout the whole building’s lifecycle, but their application remains limited in the construction industry. Building information modeling was found to be at the core of most technological integrations, but more research is needed to understand the impact of such integrations in supporting circular economy policies, standards, and assessment methods. Finally, collaborative research efforts are needed to unveil the risks of digitalization in the built environment, including risks concerning privacy and cybersecurity.

Circular economies are often framed as addressing a trio of problems: environmental degradation, economic stagnation, and social ills, broadly defined. Our paper centers on this last claim – that circular economies promise social benefits. There is a dearth of literature focused on the social dimensions of circular economies (Geissdoerfer, Martin, Paulo Savaget, Nancy M. P. Bocken, and Erik Jan Hultink. 2017. “The Circular Economy – A New Sustainability Paradigm?” Journal of Cleaner Production 143 (February): 757–768. doi:10.1016/j.jclepro.2016.12.048.), and even less attention to the meaning of social justice in the context of circular economies, let alone how it might be enacted in policy and practice. Drawing on data generated from focus groups with circular economy experts and a content analysis of US-based governmental, NGO, and business literature on circular economies, we explore whether and how justice emerges in circular economy discourse. We explore the narratives that these actors use to describe justice, and the barriers they see in achieving just and inclusive circular economies. We aim to identify the ways in which social justice is defined and discussed – or not – by the actors who seem to be most actively pushing for a circular economy (CE). Our work addresses the critical need to articulate clearly what it is we mean by social justice in relation to the CE. For if the CE is to contribute to sustainable social transformations, justice must be more than a buzzword – the CE must be just by design.

The transition towards a Circular Economy (CE) in the construction sector is essential to achieving sustainable, inclusive smart cities. This study examines the integration of CE principles into construction policies across four key global contexts: the European Union (focusing on Italy and Germany), the United States, and Japan. Through a comparative policy analysis, the research identifies best practices, implementation barriers, and the role of digitalization in advancing CE strategies. In Europe, CE is embedded in policy frameworks such as the Green Deal and the New Circular Economy Action Plan, driving the shift toward sustainable urban development. The United States, while in the early stages of CE adoption, is fostering circular initiatives at local levels, particularly in waste management and building deconstruction. Japan’s policy landscape integrates CE within a broader strategy for resource efficiency, emphasizing technological innovation. The findings highlight the necessity of a research-driven approach to inform policies that leverage digital tools, such as Building Information Modeling and Digital Product Passports, to enhance material traceability and urban circularity. This study contributes to the global effort of designing smart cities that are not only technologically advanced but also environmentally and socially sustainable through the adoption of CE principles in the built environment.

The circular economy (CE) implementation in the built environment is hindered by the complexity of CE strategies and unique nature of construction industry. Digital technologies (DTs) have been explored as promising solutions to aid decision-making and enable CE in the architecture, engineering, and construction (AEC) sector. Despite the rapid growing literature on both CE and DTs, very few studies have reviewed practical applications of DTs in the AEC sector and their intersection with CE. There is a need for a comprehensive review of the state-of-the-art applications, integrations, potential, and limitations of DT in the CE context. Through a systematic literature review, this study identified ten key DTs to enable circularity in the building sector: Building information modeling (BIM), spatial data acquisition (SDA), Artificial intelligence and machine learning (AI/ML), Internet of things (IoT), blockchain, digital twin, augmented and virtual realities (AR/VR), digital platform/marketplace, material passports (MPs), and additive manufacturing and digital fabrication (AM/DF). We provided a comprehensive review of current applications for each DT, discussed their integrations, and mapped the DT applications along a building’s life cycle. Additionally, we identified the potential of DTs in overcoming the most reoccurring barriers to CE in the built environment: design, policies and standards, assessment methods, digitalization, and business models. Finally, we discussed the main DT limitations and future research needs.