The increasing frequency of urgent projects, driven by both natural disasters and aging infrastructure, demands a global shift towards enhanced preparedness to build resilience to align with principles of the Sendai Framework for Disaster Risk Reduction (SFDRR) and the Sustainable Development Goals (SDGs). In the context of post-disaster housing in Indonesia, this requires a paradigm shift from a reactive, crisis-driven approach to a proactive one. This transition is supported by converging trends in disaster management, construction, and public procurement, which all show a move towards greater flexibility, collaboration, and proactive planning.

This research addresses the challenge of project delivery delays by developing and evaluating a procurement strategy to accelerate reconstruction. The study employs a three-phase Design-Based Research (DBR) methodology, combining literature synthesis, a comparative analysis of three case studies, and stakeholder interviews. In the first phase, Analysis & Exploration, a novel preparedness framework was developed from literature, identifying seven aspects: Community Involvement, Knowledge, Industrial Resources, Land Planning, Regulations, Funding, and Projects & Programmes. Analysis of current practices revealed a missed opportunity in project governance, where operational capacity is not fully translated into efficient and timely project outcomes, slowing down the overall recovery process. This issue is then addressed in the second phase, Design & Construction, by designing a new procurement strategy. This strategy is centered on a pre-disaster Framework Agreement that integrates design-build delivery with the pre-stocking of modular components (RISHA). In the third phase, Evaluation & Reflection, this strategy was validated and refined through stakeholder interviews.

Utilizing the framework as the assessment tool, the study concludes that a collaborative, customized framework-based procurement strategy provides a tangible mechanism to improve preparedness by shifting institutions from a reactive to a proactive stance. This research contributes to the scientific discourse by providing a practical bridge between high-level international frameworks and the realities of project delivery. For future work, it is recommended to pursue integrated governance reform, particularly establishing national land banks and ex-ante disaster financing, and to pilot the proposed strategy in diverse contexts to further refine its application.

This thesis investigates how contractual and relational governance elements can improve the performance of Bouwstroom initiatives, which are construction programs aimed at accelerating and reducing the cost of new housing construction through standardized housing concepts, collective procurement, and closer collaboration between housing associations and contracted parties. Traditional project based delivery models often lack the coordination and continuity required to meet these complex challenges, prompting interest in more integrated, programmatic approaches. Using a comparative case study of WoonST 2.0 and NH Bouwstroom, this research analyzes contractual documents and stakeholder interviews through a deductive governance framework. The findings highlight governance practices that influence lead time and cost outcomes, with the most critical being the level of standardization, purchasing and capacity guarantees, and the involvement of municipalities. While the study offers both practical and theoretical contributions to construction governance, its conclusions are limited by the focus on two cases and the evolving nature of these initiatives. The research emphasizes the importance of context specific governance strategies and recommends further research across a broader range of cases and objectives, including innovation and sustainability.

As the construction sector remains a major contributor to global emissions and resource depletion, academics, governments and worldwide industries urge for a shift from a linear to a circular economy. Circular strategies such as standardization and demountability are increasingly promoted. However, remountability, the purposeful disassembly, reassembly and reuse of building components into new contexts, remains an underexplored yet critical component of circular reuse. This research investigates how Dutch universities can integrate remountability into the construction processes of their campus buildings, given their long-term spatial commitments, public role and frontrunning ambitions in sustainable innovation.

This exploratory study combines multiple qualitative methods. A literature review, semi-structured interviews and case studies of three university projects are used to identify key strategies, enabling and inhibiting factors and contextual considerations. An expert panel assembled for a validation of the propositions . The findings demonstrate that operational strategies, such as digital documentation, flexible planning, and early contractor involvement, are central to efficient remountable construction. Additionally, cultural and organisational mindset shifts are revealed as crucial conditions for implementation. Based on these insights, the research proposes a process model and a potential analysis to guide and inspire the
integration of remountability in Dutch university campus developments.

The outcomes contribute to both academic understanding and practical application of remountability in construction, offering universities a structured yet adaptable framework to lead in the transition toward circular construction practices.

This master thesis attempts to address the polluting nature of construction industry that faces significant demands due to the trends of population growth and urbanization. The observation is made that the current take-make-dispose way of operation is outdated, unsustainable and needs to be replaced with alternative practices that minimize waste and focus on resource efficiency. To this end, this thesis advocates for the use of Circular Economy (CE) principles in the construction sector exploring the current practice, the barriers in the way of its implementation, and the enablers that can be used to accelerate their implementation.
The paper has focused on first defining the context of the scenario where the problems need to be resolved. Here the research found that the current definition of CE in the sector is extremely ambiguous and diluted with other principles, such as sustainability, reducing the effectiveness of this tool. To combat this, the thesis has developed a construction industry specific definition of CE. Moreover, the paper explored the past applications of this concept identifying previously successful sectors and factors that has led to CE thriving there.
Besides CE, the thesis contextualized the construction industry defining its inherent characteristics and comparing them to the previously defined sectors. Moreover, the research gave information about the lifecycle of construction projects, the ways in which CE principles are used, and the way in which CE affects the sector.
Following contextualization, the paper defines the problem through exploring the barriers. Here the research gave a list of 10 most critical hurdles that need to be overcome arranged in a sequence of importance. Moreover, the thesis gives a comprehensive list of 47 enablers that provide opportunities for overcoming the challenges.
Based on the available information, the study devised a general approach to barrier resolution. Here the research categorized the previously defined variables and connected them with one-another to find unique pathways to solutions. The general approach was used to create 10 targeted preliminary strategies.
The results demonstrate the complexity of achieving a systematic transition of the construction industry in a circular mode of operation. This study provides a solid academic foundation for achieving the final task. The developed 10 preliminary strategies can be used as a starting point for more in-depth solutions. For future research, paper suggests validating the general findings through real-life applications and learning from more industries about implementation and use of CE

The decarbonisation of the built environment is a key challenge in the transition towards a climate-neutral society. In the Netherlands, this sector accounts for about 40% of national CO₂ emissions, with both operational energy use and material consumption playing major roles. As natural gas is phased out, heat pumps are increasingly adopted in utility buildings due to their efficiency and compatibility with renewable electricity. However, while heat pumps reduce operational emissions, they also introduce new challenges related to material use, resource dependency, and circularity.
This research investigates how circular design strategies can support the sustainable implementation of heat pump systems in Dutch utility buildings. A qualitative, exploratory approach was used, combining a literature review with six semi-structured interviews among key stakeholders, including clients, manufacturers, consultants, installers, and policymakers. The study explored current practices, barriers, and opportunities for integrating circularity into design and decision-making processes.
Findings reveal that although technical and regulatory barriers, such as limited modularity, lack of design for disassembly, misaligned incentives, and restrictive legislation, currently hinder circular implementation, there are clear opportunities to transition from a linear to a service-oriented value chain. Key strategies include modular and standardised design, accurate system sizing, digital monitoring, and predictive maintenance. The research also highlights the importance of collaboration and clearly defined responsibilities across the value chain.
The study concludes with a set of circular design guidelines for heat pump systems, providing practical criteria for modularity, repairability, transparency, and end-of-life management. These guidelines operationalise circular principles at both the component and system levels, enabling longer-lasting, value-retaining, and low-carbon heating solutions. Future research should focus on data transparency, supportive policy frameworks, pilot validation, and system-level integration to accelerate circularity in the built environment.

This research investigates the reliability and accuracy of the Environmental Cost Indicator (ECI) in predicting the long-term environmental impact of Dutch infrastructure projects, with a particular focus on the operation and maintenance (O\&M) phase of movable bridges. The ECI is used during tenders to estimate the environmental impact of a structure in a single monetary value, however its predictive accuracy over the asset's lifecycle remains uncertain. With help of a literature review, stakeholder interviews, case study analysis and a sensitivity analysis, this thesis aimed at addressing this knowledge gap.

The results revealed that the ECI provides a rough estimate of the actual O\&M impacts, with discrepancies ranging from 9-16\%, and up to 25\% when considering unplanned renovation. Key limitations of the ECI value included misalignment between time-based assumptions in ECI tools and the condition-based strategy used in practice, exclusion of minor maintenance, incomplete material databases and insufficient monitoring protocols. The results of this study had some limitations that included the small set of case studies and the need for assumptions due to missing data.

To improve the reliability of the ECI, the recommendations included incorporating minor maintenance in standard calculations, expanding material databases, requesting ECI ranges during tenders, improving documentation, integrating environmental impact into asset management methodologies and updating ECI tools to better reflect real-life maintenance strategies. Future research should explore the ECI reliability of other asset types, develop monitoring protocols and investigate the possibilities of an adaptive ECI tool. Improving the ECI's accuracy is critical for supporting sustainable infrastructure development in the Netherlands.

The Recent advancements in digital transformation within the Architecture, Engineering, Construction, Owner, and Operator (AECOO) sector emphasize the potential for creating public value through strategic IT implementation, particularly when driven by public clients. Public clients play a pivotal role in driving digital adoption across the AECOO industry, leveraging procurement practices to encourage sustainable and innovative outcomes. Digitalization, exemplified by tools such as Digital Twins (DT) and Building Information Modelling (BIM), offers the means to achieve long-term sustainability goals, including real-time energy monitoring, lifecycle asset management, and circular economy transitions. However, the transition remains complex due to inherent industry fragmentation and limited integration of digital systems, particularly in the Operations and Maintenance (O&M) phases.
While BIM has demonstrated efficiency improvements during the design and construction phases, its benefits are less pronounced in O&M, where information continuity and integration remain challenging. A socio-technical approach, integrating people, processes, and policies, is essential for effective digital adoption, especially to address organizational silos, behavioural barriers, and knowledge gaps that hinder technological integration. Public clients, positioned as agents of change, must adopt tailored, holistic data management strategies that align with life cycle needs and public values. This research focuses on enhancing BIM's role across the AECOO lifecycle by formulating a comprehensive framework to bridge existing gaps between data requirements, project phases, and client expectations.
Through theoretical research and a case study, this study develops a multi-level framework incorporating hierarchical policy alignment, knowledge management, and information exchange protocols to address the “practical-knowledge gap” seen in digital implementations. Findings suggest that a client-led approach with strong social integration mechanisms is crucial for overcoming industry fragmentation and driving sustainable digital transformation in the AECOO sector.

This research focuses on developing a comprehensive approach to integrating health and well-being strategies into the design and construction of office buildings within the Dutch context. While international standards like the WELL Building Standard offer guidelines for enhancing indoor environmental quality, their applicability in the Netherlands is limited due to differences in local regulations, environmental factors, and cultural expectations. To address these challenges, this study combines insights from literature reviews, expert interviews, and a detailed analysis of Dutch building codes to identify critical elements affecting occupant health and well-being, such as air quality, thermal comfort, lighting, and biophilic design.

The study proposes a framework that bridges the gap between international standards and Dutch building regulations, incorporating local practices and stakeholder perspectives. It guides project teams, well-being consultants, and stakeholders through key project phases— from project definition and KPI selection to construction and post-occupancy—ensuring that well-being considerations are integrated at every stage. The framework allows flexibility in selecting Key Performance Indicators (KPIs) while maintaining mandatory health requirements and promoting real-time feedback and stakeholder engagement.

Validated by well-being experts and industry professionals, this framework provides a scalable, practical solution for enhancing the health, satisfaction, and productivity of occupants in Dutch office buildings. The research contributes to the growing demand for healthier, more sustainable office environments, offering a context-specific solution that aligns with both global best practices and local needs.

The environmental impact of the construction industry has left its mark on today’s society over the last decades, also in the Netherlands. In addition, the Dutch construction industry faces a major challenge in the replacement and renovation (V&R) task of the current infrastructure. Among others, many viaducts will be at the end of their functional lifespan. A transition to a closed resource loop along with the V&R task provides the Dutch construction industry an opportunity to extent the lifespan of elements and objects of end-of-life viaducts and reuse them in new viaducts while reducing the resource flow and its environmental impact. Although many circular initiatives and practices have been researched and developed by companies, there are still certain barriers that prevent the application of them to realise circular viaducts. The objective of this research is to identify the existing barriers that hinder a closed resource loop to enable circular viaducts in the construction industry and contribute to the circular transition.

The main barrier of circular innovations in the construction industry is the balance between supply (availability of materials) and demand (circular requirements in tenders). A sufficient volume of reusable elements must be created. Meanwhile, circular requirements are needed in tenders for the application of these elements in projects, proper assessment tools must be developed, and additional regulations and legislation is needed. In addition, there are still uncertainties with respect to the material specifications, ownership and warranty and the business case. Reusable elements are more expensive as they need to be harvested. Supply chains and collaboration form such as consortia are needed as portfolio contracts will become the new normal. Transparency is needed between the stakeholders in the industry and knowledge should be shared among parties.

A change in mindset is needed. Clients must be willing to pay more for circularity and market parties should accept the uncertainties of the transition. Additional roles and expertise’s are needed within the industry and supply chains must be organized.
Appropriate circular assessment tools have to developed, other design strategies of resource flows may assist the transition to a closed resource loop system, asset management, and additional client perspectives.

The Dutch government has envisioned and is working towards a completely circular economy in the Netherlands by 2050. However, studies indicate that the current progress of the transition is insufficient to achieve set ambitions. Transforming the resource intensive construction sector is vital for the transition to circular economy. Since infrastructure projects are primarily procured by public entities, these client organizations can drive the development of a circular construction economy by boosting market demand through strategic purchasing policies. Incorporating changes to transition from linear to circular way of working place significant demands on client organizations. A notable group feeling this pressure is the Dutch regional water authorities. These public organizations are responsible for water management at the regional level. The 21 water authorities, together build and manage huge numbers of infrastructure assets like flood defences, navigable water ways, pumping stations and waste water treatment plants. These organizations directly deal with the consequences of climate change such as heavier rains and prolonged periods of drought. Despite recognizing the urgency for the transition, the water boards struggle to progress beyond pilot projects, increase maturity levels throughout the organization, and align new policies with daily practices. While the technical know-how for circular economy transition is extensively researched, successful implementation requires organizations to also adapt internally to support the transition. Therefore, this study addresses the pressing need for effective change strategies to adjust the internal organization of public clients to facilitate the transition to a circular way of working. The study proposes an organizational change framework, that provides recommendations on what internal changes can be implemented within the water boards to accelerate their transition to circular construction. With strong theoretical foundations from existing planned change management literature, the study offers practical recommendations for change based on case studies of two water authorities- Hoogheemraadschap van Delfland and Waterschap Vallei en Veluwe.

It is well known that construction is one of the most polluting sectors worldwide. The nitrogen crisis has led to the suspension of numerous projects on multiple occasions in the past. We are also increasingly faced with scarcity of materials and the effects of climate change. Therefore, it is time for change, a transition towards more sustainability in construction. This thesis specifically researched the offshore energy sector where the Dutch and German Transmission System Operator (TSO) is enabling the transition to a more sustainable future by employing partnerships.

This thesis contributes to the current debate on partnerships by researching how a partnership in the offshore energy sector should be set up to enable achieving sustainable objectives. First, a literature review is conducted followed by an empirical research using a single case study originating from the Dutch and German TSO TenneT called the 2GW program. Semi-structured interviews were conducted and followed by a thematic analysis. For the discussion, a form of discourse analysis was deployed, specifically the dialectical-relational approach.

The results indicate that the successful launch of partnerships to enable achieving sustainability goals within the offshore energy sector is currently hampered by several obstacles. The discourse analysis revealed three main obstacles: fear of the unknown, limited market competition, and challenges in implementing the partnership approach.

The conclusion offers a comprehensive roadmap that can be utilised by similar public clients in the offshore energy sector and with some adjustment in other sectors as well (where consideration of environmental factors is essential). The research recommends fostering market incentives to increase competition, promoting clear communication and education about sustainability goals, and encouraging a cultural shift within organisations to embed sustainability into their core values.

Climate change poses a significant challenge to humanity, nature and the environment. Next to climate mitigation, climate adaptation becomes increasingly important to ensure liveable surroundings. Rising temperatures are causing more intense and more frequent heat waves, impacting housing conditions. Housing associations have the duty to provide safe and healthy dwellings for their tenants, which is why it is important to also focus on heat. This research focuses on composing a transition image and transition paths for housing associations in the Netherlands. A literature review, content analysis, and interviews with various stakeholders were conducted to assess the current state, the urgency to act, and the ambition level. 70% of the housing associations are aware of the rising problem and have any form of adaptation. The amount of adaptation is not sufficient to meet the requirement of providing safe and healthy dwellings. To accelerate the process, housing associations must continue refining their policies, stakeholders should collaborate to share knowledge, the frontrunners of housing associations should share their strategies, and differing opinions among stakeholders should be openly discussed. Additionally, housing associations should set up a proper complaints procedure and should implement solutions such as providing cool spaces, appointing tenant complex managers and utilizing the skills and knowledge of tenants with different cultural backgrounds, when technical adaptation is not possible in the short term.

Circular procurement has been found unsuccessful in two-thirds of the cases. Literature indicates that Systems Thinking (ST) is required to boost the transition to a circular building sector. This study focuses on the Initiation and Definition (I&D) phase of building projects. Currently several barriers impede the incorporation of circular ambitions in this phase, the study aims to develop a set of intervention strategies that can be used by Project managers (PMS) to overcome the barriers. ST is used and its contribution is evaluated. The research question address is “How can systems thinking contribute to the development of intervention strategies for the incorporation of circular ambitions in the initiation and definition phase of a building project?”

This is a Research through Design study, in which a Causal Loop Diagram (CLD) reflecting the process of incorporating circular ambition in the I&D phase is developed as an artifact. This CLD is used to gain insights in the dynamics in this process and to formulate intervention strategies.

The study begins with a search into the current barrier to circularity in the I&D phase making use of semi-structured interviews. It commences with the development of the CLD and formulation of intervention strategies in three sessions with a focus group. These results are discussed in semi-structured interviews with practitioners who were not involved in the focus group.

A total of twenty-six barriers were identified. The most cited barriers are the expected higher investment required for circular approaches; current financial models that are not organized for circularity and predetermined budgets that do not consider circularity. In the developed CLD six (6) themes were identified: certainty, knowledge, innovation, budget, materials, and courage. Based on this model eight intervention strategies were formulated.

Five (5) out of the eight (8) intervention strategies are related to knowledge and knowledge sharing, indicating the importance thereof. Although the initial hypothesis suggested that through ST different intervention strategies would be formulated compared to event-based thinking, the findings showed limited differences between the two. However, ST proofed valuable in improving the understanding of the dynamics and challenges in incorporating circularity by making mental models explicit and facilitating communication. Key insights highlighted the central role of ‘experience’ in improving the incorporation of circularity in the I&D phase. ST can also be used as a discussion tool among practitioners. It will help to explore circularity and surface underlying problems that impede the uptake of circularity.

The Dutch government has set climate targets to reduce carbon emissions by 49% by 2030 and 95% by 2050 with respect to the 1990 levels. The construction sector contributes to 38% of national emissions making it a major contributor to climate change. The significant stock of existing buildings in the Netherlands presents a vital opportunity to reduce greenhouse gas emissions, particularly as many of these buildings were constructed before the adoption of sustainability standards. Real estate institutional investors, who manage large portfolios of these older buildings, are key to driving this transition. While their current renovation practices focus primarily on operational carbon reduction, a whole-life carbon (WLC) approach incorporating embodied carbon is essential for meeting the Netherlands' climate targets. Despite recognizing WLC's importance, investors lack practical guidance for implementation. This research investigates how real estate institutional investors can incorporate embodied carbon considerations into their current energetic renovation processes in the Netherlands.
Through literature review and semi-structured interviews with leading real estate institutional investors from the Dutch Green Building Council working group, followed by expert panel validation, the study identifies their strategic roles in driving market demand and shaping sustainability practices, examines their current energetic renovation processes, analyzes key barriers and explores enablers for embodied carbon integration into their current energetic renovation processes.
The study develops a dual-level approach at strategic and project levels to address these barriers while leveraging identified motivators. Key findings reveal that successful WLC integration requires: (1) alignment with current renovation practices through phased implementation, (2) critical stakeholder engagement across the value chain, (3) market-driven strategies as enablers, and (4) knowledge and capacity-building. The research contributes by developing a systematic approach to integrate whole-life carbon into renovation processes, addressing barrier interconnections and stakeholder dynamics, while also offering practical, actionable strategies that align with existing workflows to help investors balance immediate needs with long-term sustainability goals.

As the Western European building stock ages, attention is increasingly allocated to the maintenance of building components, particularly mechanical, electrical and plumbing (MEP) systems. Although the latter are essential in ensuring the correct operation of a building and the safety of its occupants, they remain the crafts where the most defects are observed, resulting in significant material costs. This phenomenon partly finds explanation in the shortcomings of current condition assessment methods for MEP systems, which often poorly describe the actual state of the components.

As a result, novel approaches to estimate the condition of these building elements are investigated by industry participants. Among them, Bayesian Networks (BNs) are probabilistic models that progressively gain momentum for real-life applications. In the context of the present research, their relevance is twofold: (i) their graphical structure allows to visually model influence between large sets of variables, and (ii) they robustly handle missing data. Unfortunately, like most probabilistic models, their quantification requires extensive amounts of empirical data which is extremely sparse for MEP systems. Therefore, this thesis attempts to answer the following question: "How can Bayesian Networks be applied to estimate the condition of mechanical, electrical, and plumbing systems in the absence of empirical data?"

In their `traditional' discrete form, BNs have a limited range of applications. First, they do not allow the integration of continuous variables, which for numerous physical problems is a major drawback. Second, the number of parameters to quantify discrete networks quickly becomes intractable as the number of states and parents increases, again limiting their implementation for complex systems. Therefore, Non-Parametric Bayesian Networks (NPBNs) are adopted in this research, whose formulation is based on (conditional) rank correlations (dependence) and marginal distributions associated to each of the network's variables.

To overcome the challenge imposed by the limited availability of empirical data, several studies have investigated the use of field experts' judgments for the quantification of BNs. While the elicitation of univariate distributions has been thoroughly studied, the assessment of dependence remains an emerging topic in structured expert judgment (SEJ) literature. Consequently, this thesis focuses on the development of a method for the assessment of rank correlations by field experts, whereas a lesser effort is allocated to the elicitation of the marginal distributions.

Existing research has delved into the use of two approaches for the elicitation of dependence: statistical and conditional fractile estimates. Here, the suitability of probabilities of concordance, a third type of probabilistic assessment, is investigated. Under the normal copula assumption, common in the context of SEJ, unconditional rank correlations can be retrieved from probabilities of concordance using a set of closed-form relations. Then, the individual experts' opinions are aggregated using dependence-calibration, a performance-based aggregation method gaining momentum for NPBNs. The application of these approaches to MEP systems in discussed later in this summary.

The first step in the creation of a BN is the definition of a graph. Therefore, a classification of the MEP systems is developed and constitutes the foundation of the network. Subsequently, the factors influencing the condition of the sub-systems classified previously are identified. The literature reviewed suggests a distinction between two types of relationships: those between exogenous variables (e.g. maintenance or environmental conditions) and building components, and those between components themselves. Following the identification of these relationships, a `global' graph encompassing all MEP systems arose.

Before engaging in the quantification of this network, it is crucial to interrogate its feasibility given the time span of this research and the absence of empirical data. With 23 variables and over 30 edges, the assessment of all correlations (leave alone of the marginal distributions) is practically unrealistic solely based on experts' judgments. Therefore, the remainder of the report presents a case study on air handling units (AHUs), for which the elicitation method is implemented. The graph defined for AHUs is illustrated in the figure below.

Questions for the assessment of probabilities of concordance related to the newly created graph are then formulated, taking a similar form as follows: "Two buildings A and B are randomly selected among all non-residential buildings in the Netherlands. Given that the AHU in building A is maintained more regularly than in building B, what is the probability that the coils are in better condition in building A than building B ?"

Similar questions were created for each of the network's edges and presented to a panel of five experts, resulting in five individual correlation matrices. As mentioned previously, the experts were then evaluated using seed questions in the context of dependence-calibration. Additional questions were thus asked to the participants with regards to precipitation in the Netherlands, a choice motivated by the absence of data related to AHUs and mechanical systems for calibration. The respondents' calibration scores were then calculated using their assessments on the seed questions and the correlation matrix retrieved from empirical data. Finally, a combination of the experts' dependence structures was built using their calibration scores in a weighted average, resulting in a unique set of correlations which were implemented in the NPBN.

Lastly, two of the five experts consulted previously participated in the elicitation of the marginal distributions, either by the direct provision of the distribution or through answers to qualitative statements. The resulting model includes both marginal distributions and (conditional) rank correlations, and is ready to be validated.

To conclude, the NPBN is validated. While the lack of empirical data prevents the quantification of the model's predictive validity, a scenario analysis is performed to observe its output under different input combinations. It reveals that the exclusion of the environmental conditions from the network results in unrealistic outcomes, thus refuting an assumption made earlier in this research. Moreover, a global sensitivity analysis is conducted based on Sobol's method, which demonstrates the high contributions of all inputs to the outputs' variances. Consequently, evidence on any of the inputs substantially reduces the uncertainty in the output distributions, a comforting conclusion on the relevance of the chosen factors.

The final result of this thesis is a flowchart illustrating the construction process of a Non-Parametric Bayesian Network. It provides academics and practitioners with a foundational framework for the creation of Bayesian Networks, irrespective of the quantification method selected. While this thesis proposes the implementation of a particular expert-based elicitation method, the most suitable approach should be chosen with regards to the system modelled.

This study investigates the effects of the first phase of the Dutch two phase process project delivery method design on the information risk, the client-contractor
relationship and risk allocation between client and contractor. The two phase process is a collaborative project delivery method which is used for infrastructure projects with the objective to reduce information risk and stimulate cooperation between client and contractor. As this project delivery method is new, knowledge on the effects of the use of this project delivery method is limited.

Using desk and case study research with semi-structured interviews and an organisational behavioural theoretical lens, this exploratory research shows that the first phase of the two phase process project delivery method reduces the information risk, can make good cooperation between client and contractor possible and may help risk allocation between client and contractor. This study recommends public clients to think about the use of a two phase process project delivery method design carefully and incorporate mechanisms to end the first phase.

In traditional models of project delivery, stakeholders have clear assignments of risks, responsibilities, and liabilities. However, in today's large and complex infrastructure projects, these allocations are often uncertain and difficult to determine at the project's outset. Consequently, many of these large projects experience inefficiencies, such as exceeding time or budget. Thus, it is necessary to shift away from a 'predict and control' project delivery approach and adopt a 'prepare and commit' approach instead. Alternative project delivery methods subsequently require other contractor selection tools. This study examines the selection tool of team assessments to evaluate the collaborative potential of project teams during the tendering phase. A team assessment is a tool in which predefined collaboration competencies are assessed by independent assessors using one or more fictitious cases. Prior to constructing the cases the client and assessors identify critical moments that may arise during project execution and integrate these unforeseen moments in the cases. The client should possess a comprehensive understanding of the preconditions and limitations associated with team assessments and identify the project's characteristics and goals. Only then, a proper decision can be made on if a team assessment should be used and how the assessment should be designed and implemented. The crux is that all these considerations should be underpinned and aligned by appropriate substantiation and expert guidance. This thesis provides a framework including preconditions, restrictions, and process steps for the implementation of team assessments. Recommendations for clients, contractors, and assessors involve adequately preparing the assessment, using tailer-made competencies, developing a scoring system in which proper differentiation can be achieved, allocating a sufficient amount of time using a start-up phase to establish collaboration and streamline processes effectively, using lessons learned from the assessment in the design phase, creating consistency by having an assessor as a team coach in the design phase who reinforces the initiated collaboration, properly dealing with team member changes, maintaining a concerted emphasis on collaboration by transparently addressing it, fostering an environment of psychological safety in which mutual expectations and requirements are shared.

Sustainability has gained global recognition due to the detrimental effects of human activities on the environment, resulting in climate and weather extremes. In the Netherlands, the infrastructure sector is a key focus for policymakers, as it is responsible for a significant portion of the country's carbon dioxide emissions due to Factors such as non-renewable material use, machinery energy consumption, habitat destruction, and infrastructure type have contributed to its environmental impact (CO2 En Milieu, 2020). Dutch government has set ambitious goals to make the construction within the infrastructure sector more sustainable, aiming to reduce primary resource usage by 50\% by 2030 and achieve full circularity by 2030. These ambitions are outlined in regulations and policy, thus, form strategic ambitions (Ministerie van Binnenlandse Zaken en Koninkrijksrelaties, 2022). However, these strategic sustainability ambitions are often not fully realised as ambition erosion occurs (CROW, 2011). This research investigates ambition erosion and safeguarding strategic sustainability ambitions in the infrastructure sector within the construction process of the Ground, Road, Hydraulic Engineering sector, contributing to the broader sustainability transition goals and the realisation of strategic sustainability. A combination of theoretical and empirical research methods, including a literature review, semi-structured interviews with practitioners, and a case study based on an approach by Duurzaam GWW, were employed to understand the barriers and challenges associated with sustainability in the sector. The findings highlight the importance of clear and comprehensive definitions of sustainability that incorporate the three pillars of people, planet, and profit. Successful realisation of ambitions requires a clear continuation from strategic to tactical and operational levels within the exploration phase focusing on defining, establishing, specifying, and validating them. The research identifies 28 barriers categorized into capacity building, motivational, collaboration, and process-related themes. A comprehensive framework is proposed to address these barriers and reduce ambition erosion. The framework includes actions, conditions, steps, and instruments to mitigate barriers, enhance collaboration among stakeholders, and ensure a shared understanding of sustainability. The redesigned process focuses on defining, establishing, specifying, and validating strategic ambitions, with additional tools and methods incorporated for effective realisation. The proposed framework improves upon the existing approach by providing extra steps and conditions, identifying necessary actors and roles, and emphasizing collaboration and specific functions required to realize strategic sustainability ambitions. The enhancements contribute to a more effective realisation of sustainability goals at the project-specific level. This research provides valuable insights into reducing ambition erosion and safeguarding strategic sustainability ambitions in the infrastructure sector, contributing to the broader sustainability transition goals.

The Netherlands is facing a housing demand of 1 million homes before 2030. Most of these residences are planned to be built in and around existing cities, causing an increase in urban densities with sub-optimal indoor daylighting conditions as a result. Simultaneously, the daylight assessment methodology for buildings in the Netherlands is set to change from the Dutch NEN 2057 to the European EN 17037. The European norm uses more accurate metrics to express daylighting performance but does not consider urban context (i.e. external buildings) in the simulation models. As a result, a concern is that indoor daylighting in dense urban areas is inadequately protected. Moreover, it is unknown to what extent the urban context affects the well-being of humans, regarding visual and non-visual levels of daylight.

A multitude of daylight simulations is run and analysed in the thesis to better understand the impact of the urban context on indoor daylighting performance. Visual daylighting is assessed following the EN 17037 methodology with urban context integrated. Non-visual daylight performance is assessed using two novel metrics: melanopic autonomy and melanopic isotropy. The results have revealed that the discrepancy between simulations with and without the integration of urban context is up to 90% for realistic residences throughout the Netherlands, depending on urban characteristics and density. On average, indoor daylighting is decreased by 36% when the urban context is integrated with the EN 17037. The non-visual stimulus was found to be sufficient in residences that are compliant with EUmin levels but insufficient for residences that only comply with the Dutch building code. Sky view factor (SVF) and Building Floor were found to be useful indicators of daylighting performance in early design stages. Urban density indicators such as the FSI and OSR seem to be negatively correlated with daylighting performance.

The thesis concludes with the advice to include urban context in daylighting simulations so that bad daylighting can be properly mitigated. Effective mitigation strategies are increasing glass transmission values, interior reflectance values, and exterior building reflectance values. Another effective strategy is to avoid bad daylighting conditions in the first place by not positioning residences on the first 5 building floors in high-density urban areas. The results from this thesis can be used by daylighting designers and architects who are interested in ensuring adequate and healthy daylighting conditions in the residences they design: not only in digital environments but in the real world.

The construction sector's reliance on raw materials and the generation of waste necessitate a shift from the unsustainable linear economy to a circular economy (CE). Adopting Product-Service System (PSS) business models is crucial for achieving this transition. However, contractor companies in the building sector face barriers to implementing PSS, and there is limited knowledge about PSS in this context. This study aims to understand the state-of-the-art in PSS, assess barriers, and propose potential solutions specifically for contractor companies in the building sector.
A qualitative research method was employed, including a literature review and semi-structured interviews. The literature review encompassed 774 studies, with 45 meeting the inclusion criteria. Semi-structured interviews were conducted with professionals in the building construction sector to supplement the literature findings. This study highlighted that PSS in the building sector has the potential to enhance sustainability and circular economy efforts by promoting economic growth, reducing resource consumption, and minimizing waste.
The practical implementation of PSS in the building sector is hindered by challenges such as technological and supply chain changes, lack of financial support, organizational restructuring, establishing new customer relationships, developing new contracts, and adopting new economic models. Insufficient policies and regulations further impede PSS adoption. Nonetheless, this study highlights that sustainability, circularity, and CO2 reduction can drive the adoption and implementation of PSS.
The research identified 41 barriers to PSS adoption through the literature review and 20 barriers through interviews grouped into ten categories. These barriers encompass customers, supply chain financial, organizational, resource, knowledge, regulation or policy, environmental, social, and technology-related challenges. To overcome these barriers, nine potential solutions were proposed, including effective leadership, separated business units, training existing personnel, hiring additional personnel, cultivating long-term relationships, horizontal and vertical integration, leveraging knowledge and experience from other sectors, and learning by doing.
This study contributes to understanding PSS in the building sector and provides recommendations for practice and further research. By implementing these solutions, contractor companies in the building sector can overcome barriers to PSS adoption and increase their chances of successful implementation. The study offers guidance for efficient resource allocation and prioritization of solutions based on their effectiveness in addressing specific barrier categories. Future studies can explore customers' perspectives, conduct in-depth research on specific barrier categories, and focus on specific building systems or products to investigate potential barriers and solutions.