Gerard van Bortel

The integration of Circular Economy principles with Industrialised Construction presents a crucial pathway for addressing the housing and climate crises. Industrialised Construction encompasses a controlled manufacturing approach, including prefabrication, off-site manufacturing, and on-site fabrication methods such as 3D printing, to produce repeatable products and reconfigurable systems that increasingly integrate digitalisation and Industry 4.0 technologies. However, scholarship on practical implementation across different national contexts remains limited, whilst existing frameworks are entrenched in linear approaches. This interdisciplinary study integrates practitioner knowledge across four distinct fields categorised as policymakers and disseminators, housing providers, designers, and off-site contractors to refine a process-driven lifecycle framework developed by the authors. The framework is structured around four key circular process types, rather than linear project stages: (re)planning, (re)designing, (re)manufacturing, and (dis)assembly. Drawing on interviews and survey analysis with 31 participants working at the forefront of applied circular and industrialised housing across the United Kingdom, the Netherlands, and Spain, success factors and challenges are identified and compared. The findings highlight the critical influence of the (re)planning process, cultural and governance factors, and identify new sub-themes for the lifecycle framework. The study provides best practice insights, supporting the transfer of Circular Industrialised Housing innovations across contexts with varying maturity, particularly within social and affordable housing.

Throughout the European Union governments have reduced their investment in social housing, a trend that has also affected the Netherlands. Providers of social rental housing have faced policy changes that have challenged the dominant role in the unique Dutch unitary rental market regime. This paper examines the extent to which a revival of this dominant role can be attributed to the government’s recent interventions. It contextualises the subsequent challenges facing the housing market currently and in the future based on a review of relevant literature, policy documents, and input from interviewed experts. The largely qualitative interpretation shows that recent government interventions have given providers of social rental housing back some of the previous autonomy they had lost in terms of financing and regulation. We argue that providers of social rental housing are regaining a more important role in providing housing for low- and medium-income groups.

The latest policy and research recommendations focus on advancing transition of housing to the circular economy framework to tackle environmental and affordability challenges. A key strategy for this is industrialised construction, which combines controlled manufacturing methods with strategies that facilitate future disassembly, allowing for adaptations, maintenance, and material reuse. Despite its importance, long-term housing solutions that integrate both industrialised construction and disassembly remain rare. This study obtained insights into circular industrialised housing from the Solar Decathlon Europe competition through interviews and observations with fifteen participating teams in Wuppertal, Germany, in 2022. The competition’s build challenge provided a unique opportunity to examine the practical application of both industrialised and disassembly approaches, where teams developed highly energy-efficient, affordability-conscious, and scalable housing systems. On-site interviews with team members from diverse disciplines took place midway through the competition’s assembly phase. These were further informed by observing team Azalea’s housing disassembly in Spain, which took place shortly before reassembly in Germany. Thematic and content analyses were conducted using a predefined framework based on holistic factors and lifecycle processes. Our results reveal the critical impact of Cultural factors, particularly during the (re)design process and provide new data to aid our understanding of the (dis)assembly process. This study contributes towards the development of a circular industrialised housing framework.

Om het woningtekort op te lossen moeten er jaarlijks zo’n 90.000 nieuwbouwwoningen aan het woningbestand worden toegevoegd. Transformatie van leegstaande gebouwen en herbestemming naar woningen draagt bij aan de oplossing hiervoor. Transformatie werd tot rond 2014 gezien als een oplossing voor de leegstand op de kantorenmarkt, die in de periode 2001–2013 hoog opliep, landelijk van rond 5% in 2001 tot bijna 15% in 2013. De hoge leegstand was mede het gevolg van de dotcom-crisis en de financiële crisis, die samen met technologische ontwikkelingen en een toename in flexwerken leidden tot minder benodigde vierkante meters kantoren, terwijl er juist een overschot aan kantoren werd ontwikkeld en gebouwd. Rond 2014 is een kantelpunt zichtbaar geworden. Transformatie werd steeds vaker gemotiveerd door de vraagzijde van de woningmarkt en niet meer door de aanbodzijde van de kantorenmarkt. De aandacht voor duurzaam bouwen en het verduurzamen van de bestaande gebouwenvoorraad nam toe. In het boek Transformatie van kantoorgebouwen uit 2007 werd duurzaamheid nauwelijks genoemd. Hooguit werd transformatie vermeld als intrinsiek duurzaam, omdat het gebouw werd hergebruikt. Door toegenomen energiekosten en kosten van bouwmaterialen, en door de klimaatcrisis zijn duurzaamheidsaspecten zoals energie-efficiënt, circulair en aanpasbaar bouwen echter veel belangrijker geworden, hoewel ze nog niet overal worden toegepast. Nederland kent een grote vraag naar woningen, maar daarnaast staan veel gebouwen leeg. Op veel plekken in de Randstad staan verouderde kantoorgebouwen waar geen vraag meer naar is. In het hele land komen kerken leeg te staan door vergrijzing en ontkerkelijking. Door verplaatsing van industrie uit de binnensteden naar beter bereikbare locaties of naar het buitenland verliest industrieel vastgoed zijn functie. Schoolgebouwen komen leeg te staan door vergrijzing van de buurt. Ziekenhuizen komen leeg te staan door de invoering van nieuwe zorgconcepten en schaalvergroting. Veel winkels komen leeg te staan door centralisatie en online winkelen. Gebouwen oorspronkelijk gebouwd voor deze (en andere) functies kunnen worden getransformeerd naar woningen. Versmelting van oud en nieuw draagt bij aan behoud van identiteit. Wanneer ook nog eens sprake is van architectonisch interessante gebouwen draagt transformatie bij aan behoud van het cultureel erfgoed. Transformatie kan bijdragen aan verduurzaming van de gebouwenvoorraad en het reduceren van grondstoffengebruik en sloopafval. Transformatie zou jaarlijks 10-15% van de woningproductie kunnen bijdragen. De conclusie lijkt logisch: transformeer leegstaande gebouwen naar woningen. Maar zo eenvoudig is dat niet. De eigenaren van leegstaand vastgoed en woningontwikkelaars weten elkaar niet altijd te vinden. Transformatie is anders dan nieuwbouw en vraagt om een andere benadering. Ook zijn er allerlei financieel-economische, juridische en beleidsmatige uitdagingen, zoals onzekerheid over financiële haalbaarheid en angst voor lange procedures. Daarom hebben we het initiatief genomen om dit boek juist nu uit te geven, op het moment dat we ons middenin zowel een woningcrisis als een klimaatcrisis bevinden. Met dit boek willen wij meer inzicht geven in de kansen en uitdagingen van transformatie. We laten actoren aan het woord die ervaring hebben opgedaan vanuit verschillende perspectieven, en we bespreken projecten die de breedte laten zien van de Nederlandse transformatiepraktijk. Dit boek is geschreven door onderzoekers van de TU Delft, maar we hebben ook verschillende praktijkexperts benaderd om een bijdrage te leveren. Dit heeft een breed scala aan thema’s opgeleverd. Transformatie wordt belicht vanuit verschillende invalshoeken met een focus op haalbaarheid. Vervolgens bespreken we transformatie als een duurzame ontwerp-, ontwikkel- en beheerstrategie. De rol van verschillende actoren komt aan bod in het onderdeel perspectieven: eigenaren, beleggers, projectontwikkelaars, corporaties, architecten, gebruikers en overheden. Ten slotte presenteren we een aantal transformatieprojecten.

The built environment can become more sustainable by gradually replacing building components with circular ones. Kitchens are a logical component to be made circular, given their relatively short lifespan, product-based nature, and affordable prototypes. Since various designs for circular kitchens can be developed, understanding the feasibility of these designs is crucial for their successful implementation. This knowledge, however, remains limited. Therefore, this article aimed to determine which types of circular kitchens are feasible. Circular kitchens available or announced in the Dutch housing sector within the past five years were compared using an adapted version of the CBC generator, a comprehensive design framework for circular building components. The comparison included the Circular Kitchen (CIK), developed as part of an international research project. Data were sourced from manufacturers’ websites and online publications supplemented by interviews with two outliers to verify the results. The analysis encompassed seven circular kitchens, with two developed by established manufacturers and five by start-ups. The manufacturers mostly communicated about their kitchen’s physical design. The established manufacturers’ circular kitchens were found to be more similar to their non-circular kitchens, while start-ups applied more radical innovations. Furthermore, the kitchens that had a frame structure using technical materials or a panel-based structure using biological materials were more likely to be feasible. These findings can facilitate future circular kitchen development by improving these kitchens’ feasibility, thus aiding the transition to a more circular built environment. Furthermore, this research contributes scientifically by adapting a comprehensive design framework (the CBC generator) to compare circular designs.

The built environment can be made more circular by gradually replacing building components with more circular components during construction, renovation, or maintenance. However, many different design options can be seen as circular. Although there is a growing number of studies about circular design options, research on what makes these options feasible or not feasible in practice is limited. This type of research requires intensive, long-term involvement with practitioners. Therefore, this article presents a longitudinal case study of an exemplary circular building component: the circular kitchen. The researchers actively engaged in a co-creation with industry partners to develop a circular kitchen design, supply chain model, and business model. All the choices made from initiative to market implementation were documented. Five lessons were drawn from an analysis of the stakeholder choices that can aid the future development of feasible circular building components: about ambition, aesthetics, design scale, participation, and focus.

Affordable housing is increasingly developed, financed and managed by a mix of state, third-sector, market and community actors. This has led to the emergence of various hybrid governance and finance arrangements. This development can be seen as part of a general long-term neoliberal trend in government policies, and social, cultural and economic developments. It is therefore likely that the hybridity and variety of governance and finance of affordable housing will continue to grow. This article discusses innovative hybrid arrangements from Austria, England and Italy, in which governments, private and non-profit actors collaborate to increase the supply of affordable housing. These cases illustrate how the provision of affordable housing in a neoliberal context can benefit from the involvement of market actors and communities. Nevertheless, they also show that governments continue to play a crucial role in initiating and facilitating these arrangements.

Often institutional solutions such as structures and organisations are seen as best practices in neighbourhood renewal. Using empirical case study data from the Netherlands and the UK, this paper demonstrates that there should be more attention for the role of individual urban practitioners. The relevance of this conclusion goes beyond the domain of neighbourhood regeneration alone. Due to the new government policy paradigms (e.g. Big Society/Participation Society), welfare reforms are introduced that combine severe austerity measures with more responsibilities for individual citizens and cross-sectorial partnerships between institutions. This post-crisis participation society calls for individuals that are able to ‘make a difference’ by bridging the gap between the systems of government agencies and other institutions, and the lifeworld of residents. But what are the characteristics and working methods of highly effective ‘exemplary urban practitioners’? This paper explores the characteristics of these practitioners by analysing empirical data from neighbourhood renewal case studies using Habermas system/lifeworld concept.