Within the framework of 'Blueprints for messy cities? Navigating the interplay of order and complexity at the "Reinventing the City" conference, this paper delves into a critical aspect of circular urban development and the assessment of building material reusability. As cities like Amsterdam strive for greater liveability, resilience, and sustainability, a good understanding of circularity becomes imperative. In the dynamic landscape of urban innovation spanning mobility, renewable energy, climate adaptation, and digitization, our research focuses on the intricate domain of building material reusability. We integrate key factors influencing construction product reusability into our assessment framework. The intention of my ongoing PhD program is to establish a framework that incorporates various factors, including practical, financial, organizational, and others. These factors constitute integral elements guiding our decision-making process. The primary contribution of this study lies in the development of a BIM-integrated method designed to quantify the material reusability value. This method, rooted in numerical analysis, focuses specifically on material life expectancy. The lifespan, or in other words, the age of the material, plays a crucial role in determining the material reusability value. As the initial step in my PhD research, gaining insight into the reusability level involves investigating the impact of age. The benefits of this method are manifold. Firstly, it serves as a forecasting tool, enabling stakeholders to anticipate the amount and quality of materials obtainable from buildings at the end of their life cycle. This foresight facilitates strategic planning for material reuse, recycling, and disposal, contributing to more sustainable urban development practices. Secondly, the method provides vital information about the categories of materials resulting from deconstruction and demolition processes, namely, those suitable for reuse, recycling, and disposal. This insight assists stakeholders in making informed decisions regarding proper equipment and resource allocation for each category, thereby optimizing the efficiency of the overall process. As urbanization continues to reshape our global landscape, cities emerge as catalysts for transformative change. This transformative potential is exemplified in pioneering initiatives like Urbiquay. Urbiquay, embodies the essence of urban evolution, showcasing a commitment to sustainable urban development and progressive methodologies. The method presented in this paper is developed to contribute to such transformative endeavours, particularly in the Logiquay project's Work Package 2 (WP2), which is also my ongoing PhD research. The method's ability to forecast the obtainable materials, categorize them based on reuse potential, and guide decision making on equipment and resource allocation aligns with the objectives of Logiquay, WP2. It bridges the gap between innovative research and practical, on the ground application, offering a pathway for cities to integrate sustainability into their ongoing urban transformation.@en

This study reports on a survey on project managers' priorities. The survey used ISO 21500 as a scaffold to ask various respondents, like junior, experienced, and senior project managers, project sponsors, and students, to share their perceptions on the priorities for junior project managers. The respondent groups shared similar perceptions. Furthermore, project type and sector had little effect on junior project managers' priorities. Experienced and senior project managers shared their own priorities as well. The perceptions of priorities for junior, experienced, and senior project managers were mostly alike. However, experienced and senior project managers' priorities seemed slightly more affected by project type and sector. A session with experts in project management and teaching project management highlighted that the results for junior project managers could provide accents for introducing project management to students in higher education, provided the entire playing field of project management is also introduced.

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The circular economy (CE) is heralded as reducing material use and emissions while providing more jobs and growth. We explored this narrative in a series of expert workshops, basing ourselves on theories, methods and findings from science fields such as global environmental input-output analysis, business modelling, industrial organisation, innovation sciences and transition studies. Our findings indicate that this dominant narrative suffers from at least three inconvenient truths. First, CE can lead to loss of GDP. Each doubling of product lifetimes will halve the related industrial production, while the required design changes may cost little. Second, the same mechanism can create losses of production jobs. This may not be compensated by extra maintenance, repair or refurbishing activities. Finally, ‘Product-as-a-Service’ business models supported by platform technologies are crucial for a CE transition. But by transforming consumers from owners to users, they lose independence and do not share in any value enhancement of assets (e.g., houses). As shown by Uber and AirBNB, platforms tend to concentrate power and value with providers, dramatically affecting the distribution of wealth. The real win-win potential of circularity is that the same societal welfare may be achieved with less production and fewer working hours, resulting in more leisure time. But it is perfectly possible that powerful platform providers capture most added value and channel that to their elite owners, at the expense of the purchasing power of ordinary people working fewer hours. Similar undesirable distributional effects may occur at the global scale: the service economies in the Global North may benefit from the additional repair and refurbishment activities, while economies in the Global South that are more oriented towards primary production will see these activities shrink. It is essential that CE research comes to grips with such effects. Furthermore, governance approaches mitigating unfair distribution of power and value are hence essential for a successful circularity transition.@en

Comprehensive understanding of the merits of bottom-up urban development is lacking, thus hampering and complicating associated collaborative processes. Therefore, and given the assumed relevancies, we mapped the social, environmental and economic values generated by bottom-up developments in two Dutch urban areas, using theory-based evaluation principles. These evaluations raised insights into the values, beneficiaries and path dependencies between successive values, confirming the assumed effect of placemaking accelerating further spatial developments. It also revealed broader impacts of bottom-up endeavors, such as influences on local policies and innovations in urban development.@en

Research on the circular built environment has to date focussed mainly on technical aspects of circularity in the built environment, emphasising the development of methods, tools, and frameworks to facilitate technical solutions that can narrow, slow, close, and regenerate materials cycles. Despite progress made in understanding the technical possibilities of circularity in the built environment, and although there has been longstanding acknowledgement that new forms of inter- and transdisciplinary collaboration are needed to accelerate and scale up solutions for the circular built environment, studies have also consistently highlighted the lack of collaboration as a significant barrier. In this position paper, we argue that existing research tends to focus on collaboration at the level of the building project, and this neglect calls for developing longer-term collaboration for circularity as a multi-level transition that considers the interactions between multiple parties involved in extended and multiple product lifecycles traversing multiple scales beyond the building project.@en

The emergence of organic planning practices in the Netherlands introduces new, non-conventional, local actors initiating bottom-up urban developments. Dissatisfied with conventional practices and using opportunities during the 2008 financial crisis, these actors aim to create social value, thus challenging prevailing institutions. Intrigued by such actors becoming more present and influential in urban planning and development processes, we aim to identify who they are. We use social entrepreneurship and niche formation theories to analyse and identify three types of social entrepreneurs. The first are early pioneers, adopting roles of a developer and enduser, but lacking position and power to realize goals. Secondly, by acting as boundary spanners and niche entrepreneurs, they evolve towards consolidated third sector organizations in the position to realize developments. A third type are intermediate agents facilitating developments as boundary spanners and policy entrepreneurs, without pursuing urban development themselves but aiming at realizing broader policy goals. Our general typology provides a rich picture of actors involved in bottom-up urban developments by applying theories from domains of innovation management and business transition management to urban planning and development studies. It shows that the social entrepreneurs in bottom-up urban development can be considered the result of social innovation, but this social innovation is set within a neoliberal context, and in many cases passively or actively conditioned by states and markets.

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Despite the efforts of governments and firms, the construction industry is trailing other industries in labour productivity. Construction companies are interested in increasing their labour productivity, particularly when demand grows and construction firms cope with labour shortages. Off-site construction has proved to be a favourable policy to increase labour productivity. However, a complete understanding of the factors affecting construction labour productivity is lacking, and it is unclear which factors are influenced by off-site construction. This study developed a conceptual model describing how 15 factors influence the construction process and make a difference in labour productivity between off-site and on-site construction. The conceptual model shows that all 15 factors affect labour productivity in three ways: through direct effects, indirect effects and causal loops. The model is a starting point for further research to determine the impact of off-site construction on labour productivity.

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Construction supply chain management (CSCM) has been seen as a source of improved performance for construction at a firm and interfirm level. The control and the improvement of the interaction between the supply chain and the construction site have previously been formulated in four roles of CSCM. Recently advanced construction logistics have become a field of particular interest of CSCM because of the potential to improve both efficiency and environmental performance. The research reported was aimed at advancing construction logistics in practical cases to improve and assess the efficiency of logistics and mitigation of environmental effects, notably in urban areas. Logistics measures taken included establishing dedicated logistics centres for consolidated delivery of materials to construction sites. The research showed considerable effects of increased efficiency in the supply chain and on construction sites, as well as reduced environmental impact on the surroundings. In conclusion, the research results have led to the extension and reformulation of the four roles of CSCM putting more emphasis on improved logistics and environmental performance.@en

Refurbishment projects notably for social housing are special kinds of project for many reasons, including inflexible existing stock, low available budgets, involvement of residents staying in their homes during construction. Lean tools could be helpful not only during construction, but also in the preparation of projects including requirements definition, budgeting, design, engineering and planning. The preparation phase also has typical peculiarities including political and social aspects, and is often time and cost consuming. Much lean research has focussed on improving the construction of new built and private sector projects. In contrast this paper aims to demonstrate the merits of lean tooling in the preparation phase of social housing refurbishments. The research reported examined lean tooling applications and their effects on project success in selected case studies of social housing refurbishments in the Netherlands. The research was a design based action research shaping a preselected catalogue of tools i.e. lean toolbox. Next tools were selected together with practitioners, for application in the case projects. After those interventions interviews were held to registers effects on critical success factors in the projects. Most of the tool applications from the lean toolbox approach appeared to be effective in harnessing critical success factors in the projects.@en

Rapport voor Crow, waarin een set met instrumenten voor een duurzame bouwlogistiek in elk van de fasen wordt gegeven. Hierbij is te denken aan meer ketensamenwerking, minder transport, en andere modaliteiten.@en

This chapter explores how lean is different from mainstream thinking, and in what way is it different or similar to traditional thoughts in mainstream management. It examines the specific characterisation of supply chain management, which practices fall into supply chain management, and which are the theoretical approaches specific to supply chain management. How the conceptions of lean and mainstream management reflect in supply chain management, both practically and theoretically, is also discussed. The chapter also analyzes the way in which supply chain management, especially in its lean form, are contingent on the characteristics of the construction industry and firms operating within the industry. By putting the lean lens on supply chain management, the chapter defies mainstream explanations of construction supply chain management and triggers further explanation and exploration of lean applications to construction supply chain management that has been lacking in theory and not sufficiently applied in construction practice so far.

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Productivity in construction is relatively low compared to other industries. This is particularly true for labour productivity. Problems that contribute to low labour productivity are often related to unorganised workspace, and inefficient organisation of work, materials and equipment. In terms of time use, site workers spend time on various activities including installing, waiting, walking etc. In lean production terms time use should be value adding and not wasteful or non-value adding. The study reported in this paper has endeavoured to measure the time use and movement applying an automated data system. The case study reflected a limited application to a specific kind of activity, namely doors installation. The study investigated time use and movements based on interviews and on automated detection of workforce. The interviews gave insights in the time build-up of work and value-added time use per day. The automated tracking indicated time intervals and uninterrupted presence of site workers on work locations giving indications of value adding time. The time measurements of the study enable comparison of time use categories of site workers. The study showed the data system calculated the same amounts of productive and value adding time one would expect based on the organisation and characteristics of the work. However, the discussion of the results underlined that the particular characteristics of individual projects and types of team work organisation may well have an impact on productivity levels of workers. More application and comparative studies of projects and further development and extension of the automated data system should be helpful.@en

Urban interventions initiated by citizens, (end)users and small independent professionals have increased in number since the recent economic crisis. Many of these ‘bottom-up’ Urban Area Development projects (UAD’s) result from citizens’ dissatisfaction with conventional practices or give room for ambitions to self-organization. Current Dutch policies, in line with EU policies, emphasize the potential and added value of these bottom-up developments in co-creating healthy, inclusive and resilient cities. However, theoretical knowledge of what these ‘bottom-up’ projects are, and proven methods of how they can be successfully supported and governed is lacking. This paper aims to contribute to filling this gap. It starts with a literature review which identifies the characteristics of ‘bottom-up’ UAD’s and what distinguishes them from conventional, ‘top-down’ organized UAD’s. Drawing on bodies of literature, a framework was developed to analyse the institutions of UAD’s. It introduces a number of variables, influencing processes and outcomes of UAD’s. A first exploration of two distinctive Dutch cases shows to what extent this framework is valid and how different types of UAD’s show a different emphasis on - and implications of - the variables. It also provides a richer picture of the drivers within strategies, developed by actors. Further analysis shows a dependency on - and necessary collaboration between - bottom-up and conventional top-down actors in order to achieve successful bottom-up UAD’s, amongst others. Future, extensive case-studies within this research will examine the tentative proposition, that this ‘merge’ or ‘cross-over’-approach is essential in order to successfully govern and support bottom-up UAD’s.@en

De afgelopen jaren is onderzoek gedaan naar nieuwe concepten voor bouwlogistiek en bij negen proeftuinen in binnenstedelijk gebied is aangetoond dat hier forse winst is te behalen in termen van besparingen op logistieke kosten en bouwtijd, betere doorstroming, minder schadelijke uitstoot en minder hinder voor de omgeving. Zo bleek het mogelijk om het aantal binnenstedelijke ritten van en naar de bouwplaats met zo’n vijftig tot tachtig procent terug te brengen. Voor goede bouwlogistiek is afstemming en medewerking binnen de keten cruciaal. Alle spelers dienen tijdig betrokken te zijn. Bouwlogistiek bestaat uit allerlei maatregelen die effect hebben op het transport en op het bouwproces. Door te meten en te monitoren zijn de effecten van verschillende maatregelen in het onderzoek aangetoond en nieuwe inzichten en lessons learned opgedaan die worden meegenomen in volgende bouwprojecten. In totaal zijn negen proeftuinen begeleid, waarvan er bij drie uitgebreide gegevens zijn verzameld en ook besparingen aangetoond. Bij de andere proeftuinen zijn vooral kwalitatief lessons learned opgedaan. Bij het Voorzetgebouw/Paviljoen van VolkerWessels Bouwmaterieel is 50% ritten in de afbouwfase bespaard, bij het Noordgebouw van Dura Vermeer 65% in ritten in de afbouwfase en bij het Mariskwartier van Van Wijnen is 80% in ritten in de ruwbouwfase bespaard. Andere proeftuinen hebben laten zien dat het meten en monitoren van bouwlogistiek niet altijd eenvoudig is en het invoeren van bouwlogistiek zelf al lastig genoeg is. Vragen die opdoemen zijn: wie bepaalt of en zo ja welke maatregelen op de bouwplaats worden toegepast, de directie of de hoofduitvoerder en wie bepaalt hoe producten worden ingekocht, is dat op laagste prijs of wordt logistiek ook meegenomen. Allemaal vragen die van groot belang zijn voor een efficiënte logistiek van, op en naar de bouwplaats. Daarnaast leeft de vraag welke rol de gemeente gaat spelen; of zij bepaalde logistieke werkwijzen gaan verplichten bijvoorbeeld via aanbestedingen? Een andere belangrijke vraag is wie er opdraait voor de eventuele kosten van de bouwlogistieke maatregelen. Dit rapport geeft hier antwoord op. Verder komen de ontwikkelingen rond ketenregie, BIM en ICT aan bod. Ketenregie over alle vervoersstromen gekoppeld aan het bouwproces, en over alle partijen van producent tot op de bouwplaats, staat of valt met de juiste ondersteunende ICT-middelen. Daarin speelt de beoogde 4C Control Tower een cruciale rol in planning en besturing op strategisch, tactisch en operationeel niveau. Er blijkt nog een flinke ontwikkelingsslag nodig om BIM geschikt te maken voor bouwlogistieke planning en besturing. Daarnaast is gekeken naar betrouwbare dataregistratie in het bouwlogistieke proces door een pilot waarin nieuwe technologieën gebaseerd op Internet of Things (IoT) een oplossing bieden. Eigenlijk is er geen enkele reden om niet nu al met bouwlogistiek te beginnen, al is het maar in het klein met eenvoudige maatregelen. Zorg dat tijdig in het proces alle partijen erbij betrokken worden, van architect tot vakkracht op de bouwplaats, zorg voor draagvlak in het hele team. Dan zijn de drie proeftuinen met de mooie besparingen straks geen uitzondering meer maar regel.@en

The construction and renovation of the building envelope represents a significant fraction of a project’s life-cycle costs. It also has a determinant effect on the potential reduction in energy use, as well as on the improvement of the building’s indoor comfort. Nevertheless, the challenge of a low rate and depth in building energy renovations cannot be solved through technological innovation alone. Instead, the Façade Leasing research project proposes a systemic shift in economic and business incentives, towards the creation of a performance-based contracting model for integrated façades.

Façade Leasing explores an integral, cross-disciplinary model promoting accelerated strategic investment in energy-efficient building envelopes. A focus on performance delivery, rather than product sales, would in turn impulse ongoing innovation in products and management processes. It would also provide the foundations for Circular Economy strategies for the reuse and remanufacturing of building components, leading to a potential reduction in primary raw material consumption across the façade industry.

This study starts by describing the “Façade Leasing pilot project” developed and built at the TU Delft campus by a consortium of açademic and industry partners. It then outlines the main drivers and barriers to the commercial application of the Façade-as-a-Service concept in the Dutch public, nonresidential real estate sector, from the perspective of four key stakeholder groups: Demand drive, or the decision-making process of real estate developers, owners, and managers; Supplier readiness, or the necessary reorganization of products and processes along the supply-chain; Finance, or the distribution of financial resources bridging the gap between initial investment cost and longterm service fees; and governance, or the necessary regulatory innovation required to separate ownership of building and façade.

The research shows that, while further research and validation work is needed to test these principles in a controlled, case-study setting, the potential for façade-as-a-service delivery is within reach under the current legal and economic environment.@en

his study investigates whether integrative and collaborative practices of the construction industry can be exclusively attributed to integrated project-delivery methods or whether traditional project-delivery methods also foster integration within project-based design teams. Project managers assessed team collaboration and the integration of teams into 46 construction industry projects in The Netherlands. Explanatory factor analysis (EFA) was used to identify the components that explained collaboration and integration within project design teams. Using analysis of variance of factor scores, the main finding of the study was that, in the construction industry, collaboration is an independent component in integrative and collaborative practices that can be reliably assessed in research. Furthermore, this study provides evidence suggesting that both traditional and integrated project-delivery methods might lead to collaboration over time. The third finding is that different project-delivery methods were not significantly different in terms of the dimensions of integration and collaboration, except in the component of inclusive decision making within the building team and for strategic partnering. The findings suggest that relying on the type of project-delivery method is not sufficient for managers communicating about the level of supply chain integration and collaboration.@en

This paper presents a research endeavouring to model site work in a 4D BIM model. Next simulations are performed with this model in 5 scenarios including specific interventions in work organisation, notably changing positons of facilities for site workers. A case study has been done in a construction project in the Netherlands. The research has showed the possibility to model time use of site workers in 4D BIM. Next the research has showed potential to perform and calculate specific interventions in the model, and prospect realistic changes in productive time use as a result.@en

The way in which construction logistics is organised has considerable impact on production flow, transportation efficiency, greenhouse gas emissions and congestion, particularly in urban areas such as city centres. In cities such as London and Amsterdam municipalities have issued new legislation and stricter conditions for vehicles to be able to access cities and city centres in particular. Considerate clients, public as well private, have started developing tender policies to encourage contractors to reduce the environmental impact of construction projects. This paper reports on an ongoing research project applying and assessing developments in the field of construction logistics in the Netherlands. The cases include contractors and third party logistics providers applying consolidation centres and dedicated software solutions to increase transportation efficiency. The case show various results of JIT logistics management applied to urban construction projects leading to higher transportationefficiencies, and reduced environmental impact and increased production efficiency on site. The data collections included to-site en on-site observations, measurement and interviews. The research has shown considerable reductions of vehicles to deliver goods and to transport workers to site. In addition the research has shown increased production flow and less waste such as inventory, waiting and unnecessary motion on site.@en

The vast amount of previous research on project management competence does not provide a basis for educational needs. Analyzing previous research poses two challenges: the lack of a uniform list of competences, necessitating a taxonomy, and the use of importance as a criterion, favoring general important competences. Criticality is introduced as the competence a project manager adds to the team. Validation research using criticality and the taxonomy among experienced Dutch project managers is more comprehensive and provides a lesser focus on general important competences than previous research. Criticality focuses more on the essence of the profession.@en