The building sector's contribution to global CO2 emissions requires innovative approaches to reduce its environmental impact. Mass timber offers a viable solution due to its lower global warming potential during production and its ability to temporarily store carbon. This storage not only reduces radiative forcing, but also removes carbon from the atmosphere and can help mitigate climate change. The inclusion of biogenic carbon flows in LCA is therefore essential to accurately assess the environmental performance of a mass timber building. However, European standards do not include this in their guidelines for conducting LCA of bio-based materials. A systematic review of LCA studies on mass timber buildings highlighted the low presence of biogenic carbon flows and found the need for an advisory decision tree framework for accounting for these flows. Through an applied case study of a recent mass timber building project in Rotterdam, this research itself demonstrated that prolonged storage periods of wood products in construction can lead to a negative Global Warming Potential (GWP) score, thus supporting the inclusion of biogenic carbon in LCA models. However, the variability of LCA methodologies makes it difficult to compare studies on bio- based materials. To address this, a harmonization process among standardization organizations is recommended. Therefore, the decision tree framework is intended as a first approach to guide practitioners on how to model biogenic carbon, emphasizing the importance of accounting for temporal storage and forest dynamics based on a GWP-bio value.

The building sector in the Netherlands contributes significantly to carbon emissions, with a substantial portion arising from embodied carbon in materials. Despite government efforts, the industry struggles to meet emission reduction targets. This thesis, examines the material selection process during the design phases of building projects to reduce carbon emissions. A qualitative approach, including a narrative literature review and semi-structured interviews, identified key barriers in decision-making, such as delayed decision-making, lack of data, and stakeholder misalignment. The study highlights the preliminary design phase as a critical “sweet spot” for impactful decisions and recommends early goal-setting, stakeholder collaboration, and continuous budget checks to enhance the sustainability of building projects.

Global warming is primarily driven by the emissions of carbon dioxide resulting from human activities. The construction industry, driven by urbanization and population growth, plays an important role in this due to its resource-intensive nature. Buildings account for nearly 40% of global energy consumption and one third of associated greenhouse gas emissions. Additionally, the government’s goal for the Netherlands is to reduce greenhouse gas emissions by 55% in 2030 and to achieve climate neutrality in 2050. The focus to reduce CO2 emissions used to be on lowering operational energy emissions, but due to the increase in energy-efficient and net-zero buildings this focus is now shifting. As operational emissions drop, materials' emissions gain importance, shifting environmental studies toward reducing embodied energy.
One potential solution to address this challenge of reducing carbon emissions is the adoption of circular economy principles in the construction industry. Circular strategies, such as reduce, reuse, recycle, and recover, have the potential of minimizing waste, reducing resource consumption, and reducing CO2 emissions. However, it is unclear how these strategies compare to each other in terms of their carbon footprint.
Therefore, this research aims to assess and compare the embodied carbon benefits of the circular 4R-strategies with different structural materials in the building industry. Through life cycle assessments (LCAs) of case studies spanning a 40-year lifespan, the study evaluates the effectiveness of downsizing, reuse, and recycling strategies in reducing emissions. A 5% reduction in material use led to a 5-10% decrease in emissions, while a 10% reduction yielded a 9-16% reduction. The implementation of a moderate reuse strategy has been demonstrated to result in reductions in emissions ranging from 16% to 24% for timber and steel structures. Moreover, the results showed that it is possible to achieve significant emission savings of around 60% to 70% through the implementation of an extensive reuse strategy, where a greater proportion of materials are reused. The effectiveness of recycling strategies in reducing emissions varies considerably, with potential emission reductions of between 55% and 70% for concrete, between 27% and 70% for steel structures and between 12% and 37% for timber. The effectiveness of this strategy is highly dependent on the maximum percentage of recycled content the material in question can have.
A comparative analysis reveals that timber generally offers superior CO2 reduction over concrete and steel in the short term. However, concrete with an effective circular strategy and a lifespan of around 80-100 years can outperform a timber building with a lifespan of 40 years. Concrete with high recycled content and steel with significant reuse show notable CO2 reduction potential. Tipping points for concrete and steel structures occur around 80 years, where concrete becomes more favourable than steel due to lower replacement rates.
The research contributes to practice through the integration the study’s outcomes in design guidelines and a mathematical optimization decision model, that facilitate informed decision-making among clients, managers, architects, and suppliers during early design phases.

This thesis examines the potential of small, low-carbon, (near) zero-energy dwellings as a solution that would both address sustainability challenges and answer to the growing housing shortage in North-West Europe. It adopts a multidimensional outlook that encompasses institutional, social and technical aspects surrounding the dwellings. The institutional aspect is addressed through an investigation of financial, legislative, technical and cultural barriers to the implementation and uptake of small, low-carbon, zero-energy dwellings. A context specific approach is adopted taking into account contextual peculiarities for the formulation of more refined policy suggestions. The social dimension is addressed first from the perspective of market supply through an investigation of the perceptions of housing professionals. The distinction between perceived versus actual barriers identified by housing professionals is made highlighting a potential desynchronization between policy developments and local practice. Accordingly the study calls for innovation in information dissemination between policy and local practice and between housing professionals themselves. The social dimension is then addressed from the perspective of market demand through an investigation of consumers’ current housing preferences. The assumption stating that, due to an increase in smaller, elderly, and lower-income households, current housing preferences are leaning towards smaller dwellings is refuted underlining the importance of distinguishing between smallest and smaller dwelling sizes. Lastly, the technical dimension is addressed through conducting a partial life cycle assessment that focuses on the embodied carbon of the dwellings. Both downsizing and the use of low-carbon materials such as timber are investigated as embodied carbon reduction strategies. Together, the three dimensions provide a holistic evaluation of the potential of small, low-carbon, zero-energy dwellings as a solution while addressing the complexity in reaching sustainable outcomes.

Environmental harm is an influencing factor in policymaking, as climate pressures are frequently on the global agenda. An important tool to guide decision-making in the construction industry is the life cycle assessment (LCA) methodology, where the quantification of environmental harm is realised. In the method, an estimation of numerous environmental impact indicators can be made by assessing the various life cycles of a product, material, or process. Bio-based materials have been considered a valuable option to mitigate climate change. However, the LCA methodology appears to disregard certain characteristics of the material that could potentially improve their corresponding results. With the growth of bio-based materials, atmospheric carbon is stored as biogenic carbon and subsequently released at the end-of-life, the last life cycle phase of a material. The current methodology is unable to credit such storage, as it models all emissions through the life cycle as if they occurred at the same time. This research aims to explore the various options to comprehend, assess, and credit the storage of biogenic carbon. First, the different approaches to assess the storage of biogenic carbon, that are described in the literature, are assessed. Second, various methods to credit the timing of emissions in the LCA methodology will be elaborated upon. Third, the different currently active European standards are described. For biogenic carbon assessment, three methods were described: the 0/0 method, the -1/1 method, and the dynamic method. Here it was concluded that, respectively, complexity and accuracy increased, making practical implementation difficult but potentially valuable. Especially, the dynamic approach is shown to be a promising tool to accurately assess temporalities within the life cycle of a product. For possible crediting mechanisms, three methods were discussed: the Moura-Costa, Lashof, and ILCD crediting methods. Each method was based on specific assumptions, which resulted in varying credit strengths. In general, each crediting mechanism answered the demand for crediting delayed emissions, but to decide whether one of the methods is better suited than the other, further research is necessary. It is found that the organisational complexity of standardisation within the European Union influences possible alterations in the LCA. However, the research can conclude that the methodology is currently unable to capture the benefits of biogenic carbon storage, and by looking into potential crediting mechanisms, this limitation can be answered. Depending on the demand of our climate and, therefore, of policymakers, possible crediting mechanisms for the storage of biogenic carbon can be considered to be implemented through the LCA methodology.

This thesis project investigates the potential of the 'creative condenser' within the context of Berlin as an approach to the ‘public condenser’, a term introduced by the board of the Public Building graduation studio within the MSc Architecture track at Delft University of Technology.

The built environment is responsible for a substantial amount of energy use and greenhouse gas emissions. To improve energy efficiency and reduce environmental impacts, buildings can be renovated or replaced with more energy-efficient alternatives. Although new buildings often cause less environmental impacts from operating energy use, the higher material requirements cause additional environmental impacts. Housing corporations own more than 25% of residences in the Netherlands and need to decide between different energy efficiency improvement methods for their building stock. Therefore, the proposed thesis has the following research question: What are optimal building renovation or replacement solutions for housing corporations to improve energy efficiency and reduce environmental impacts in the context of the Dutch climate goals? Environmental impacts of materials and energy have been calculated according to the MPG+ method, which follows the life cycle assessment approach. The results show that extensively renovated porch flats and new buildings lead to similar amounts of environmental impacts if both use a collective heat pump and are insulated according to nearly-zero energy building standards. The comparison between the environmental impacts of extensive renovations and building replacement depends on the expected building life span after the intervention, the quantity of solar panels, and the use of sustainable materials. Renovations including lower energy efficiency levels or fossil energy sources cause more environmental impacts. The MPG+ method aligns with the Dutch policy context but lacks transparency, completeness, and data certainty. The alternative scenarios in this study are compared per square meter, so the overall environmental impacts may increase if the relative apartment size per resident is greater in the new building. Considering the Climate Agreement, the housing crisis, and many uncertainties, extensive renovations are recommended as a no-regret solution for housing corporations.

Waste is a natural process, a pervasive material, an invaluable resource; a crucial element in the way human society views, orders, and designs its spaces. The issue of waste is a modern urban invention and a controversial topic for both global culture and urban ecology, and stems from the consumptive habits of modern society and the throwaway culture that promotes the disposability of products. The assumption that the product is more important than the materials that make it up is particularly prevalent in complex everyday items such as electrical and electronic equipment. The waste electrical and electronic equipment (WEEE) stream is the fastest growing waste stream in the world. These complex products, made mostly of glass, plastic and metal, but also of valuable resources such as rare earth metals are destined to be landfilled and if lucky, to enter the recycling loop. Ironically, recycling, a waste practise touted as "the" solution to the waste problem regardlessly encourages consumptive habits and ultimately supports the interests of the same system that creates the waste problem. On the other hand, the issue of urban waste arises from the processes of contemporary urbanisation, economic change and rapid population growth, and spans technical, environmental, social, economic, and political layers. Agglomeration of problems across the layers of waste ecologies results in delays in their spatial synchronisation and waste ecology produces waste landscapes, which are the infrastructures of waste streams and their consequential landscapes.

The municipal waste stream is not the largest; however, it generates the most waste landscapes in the city and therefore an important issue for urban life. London has long joined the global attempts at transforming "take-make-waste" habits and the linear, fixed, closed systems into flexible, complex, circular ones. However, the delay in transforming the monofunctional structures of industrial waste processes into circular multifunctional infrastructures of resource recovery still results in vast, polluted sites of accumulated urban waste. Waste collection, treatment and disposal processes continue to be harmful to the environment. Waste landscapes remain industrial in structure and image, seen as disruption to urban life, and therefore, appear as a strange non-city fabric. The metropolis continues to rely on waste landscapes, producing even more of them and pretending to contribute to the socio-environmental condition of the city.

The research aims to find ways to catalyse an interception in urban waste ecology and generate alternative pathways for material flows in the city. The results of the graduation project prove that waste materials can be reclaimed within the city by linking waste flows with other urban flows and generating opportunities for waste landscapes with new programmes and values. As a proof concept, this coupling is realised for WEEE stream and collaborative work spaces of arts, crafts, and technology, which illustrates a creativity-based alternative to materials recovery in the city.

In this paper, design principles for a co-housing project focused at young adults (18-27 years old) wishing to live in the Tarwewijk in Rotterdam Zuid are being proposed. These principles are based on literary research, reference projects, fieldwork and workshops held for students familiar with the design location. Topics that are touched upon are affordability, co-housing principles and the living wishes of young adults wishing to live in Rotterdam Zuid. While the target group did not perfectly fit the proposed target group, results were interpreted as if they were. The most important findings through different methods of research, among others, include that different types of housing should be realised, the building should contain several shared facilities in rooms which have a flexible floorplan, the neighbourhood should be involved in shared spaces, housing units should be designed as small and with as little walls as possible and that bathrooms and bedrooms should always be private. These results were combined into a design brief specifically created for the Tarwewijk in Rotterdam Zuid, yet the basic principles can be implemented in other affordable co-housing projects as well.

This thesis examines the energy performance of dwellings of Dutch non-profit housing associations towards a future sustainable housing stock. Improving the energy performance of dwellings aims to improve the quality of dwellings and therewith to lower the actual energy consumption. Lowering the actual energy consumption of dwellings contributes to the battle against climate change. This thesis addresses four studies. Study 1 assesses the energy performance progress of over two million dwellings of Dutch non-profit housing associations between 2017 and 2020. It gives insights into the development of the housing stock, the effect of changes of and within the stock, the effect of characteristics of housing associations and it relates the improvement of the energy performance to the sectoral goal. Study 2 assesses advanced models to improve estimations of actual energy consumption of dwellings and therewith to better estimate the effect of renovation measures on actual energy savings. Study 3 assesses the energy performance of dwellings with heat pumps. It gives insights into the energy performance of dwellings with heat pumps as a promising renovation measure towards a future sustainable housing stock. Study 4 assesses the process to create a model to benchmark the energy performance in a changing policy context. The four studies contribute to the understanding of the improvement of the energy performance of dwellings of non-profit housing associations towards a future sustainable housing stock.

This project is about the transformation of a shopping mall called 'the Molenpoort' located in the city centre of Nijmegen. From this location I try to enter in conversation about - and most of all - with architecture. I try to challenge what the change of perspective from people to buildings can mean when looking at a city, to the interrelationships between buildings and building elements and what it can mean for our realisation of time. What can we learn about time and trends we find nowadays in architecture? What time is this place? By anthropomorphizing buildings I try to apply terms coming from social studies on buildings - on architecture. The project will show that a very refined way of looking at several architectural scales is reached while at the same time complexities related to construction, climate design, architecture and urban design are covered. Key terms which are finding their way on all these facettes are reciprocity and kinship.
Moreover, this whole research is done within the theme of our studio 'Bricolage' which encouraged me to intertwine research and different design methods with each other resulting in a very diverse set of products - from film fragments, rendering images, collages, working models to products like technical one-point perspectives drawings made by hand.
In the end, the most important notion for me was that a building as a character is not interesting if it is completely straight, following the engineered rules, like a real person is not interesting without an internal conflict. I dare to say now that the building becomes a speaking character from its peculiar irregularities, strange features, awkward bendings. Let’s embrace and celebrate architecture from here and give it a face.

I decided to upload my work together with the final presentation text and my design journal. In that way I hope that people can follow the experimental and challenging way of looking and - maybe one day - want to share some thoughts with me.

The Urban Heat Island effect increases the air temperature in cities compared to rural areas because cities have a lot more hardened surfaces than rural areas. As the amount of people living in cities increases and the global air temperatures rise, these negative effects will increase and mitigation action has to be taken. This research investigates how technical, household and institutional characteristics influence the adoption of Urban Heat Island mitigation solutions in existing neighbourhoods in the Netherlands. Through a desk study, expert interviews and agent-based model the effect of these characteristic on the adoption of green roofs, green façades, green gardens and cool roofs by households is researched. The results show that several characteristics found in literature do not have a significant effect on the fraction of adopted solutions and that there is no significant difference between the four investigated Local Climate Zones. It is concluded that only the energy reduction effect of a solution has a significant influence, that households with a higher income and households that own their dwelling adopt more mitigation solutions, that households in owners’ association adopt less solutions and that introducing or increasing the subsidy for green roofs or cool roofs increases the adoption of these solutions but not the average air temperature. Furthermore, the results show that households will mostly adopt green roofs. The outcomes of this research can be used by policy makers to differentiate policies between neighbourhoods and the model itself can be adapted to use it for other cities or neighbourhoods.

According to the European Commission, buildings are responsible for approximately 40% of the EU energy consumption and 36% of the CO2 emissions, resulting in the largest energy consumer in Europe. Especially, the reduction of energy consumption for heating of residential dwellings has gained more and more interest in the last decades. Although some reduction has been achieved by implementing passive or active strategies and improving the thermal performance of new or renovated dwellings, the decrease is found to be lower than predicted by the energy performance models. One possible reason is that the existing thermal comfort models, the PMV and the adaptive thermal comfort model, are not appropriate for all different types of buildings and climates, resulting in inaccurate predictions of thermal comfort and leading to amounts of energy use different than the actual ones. In addition, the occupants’ behaviour, which is determined by their thermal comfort preferences might play a significant role on the energy use which needs to be explored. Therefore, the main topic of the current thesis is to explore the relationship that different parameters such as dwelling and installation characteristics, indoor and outdoor climate parameters, household and physiological characteristics as well as occupants’ behaviour have with thermal comfort and energy use.

A measurement campaign took place within the context of the OPSCHALER project and data related to thermal comfort perception, indoor climate and energy consumption was collected for 96 dwellings in the Netherlands during periods ranging from two to twelve months over a one-year period (2017-2018). The gathered data included both quantitative and subjective data. The quantitative data included the indoor climate data (air temperature, relative humidity, CO2, presence), the gas use and the electricity use collected through smart meters and sensors. The subjective data related to comfort was gathered by a comfort mobile application where users recorded their thermal sensation and other comfort related parameters (thermal preference, clothing, metabolic activities, actions), while questionnaires and inspections did also take place. This data was analysed using different types of graphical representation (bar charts, pie charts, stacked bar plots, scatterplots) as well as statistical tests such as chi-square tests, regression analysis, Kruskal-Wallis and correlation tests. Due to limited or unavailable data only 78 dwellings were included in the analysis, while the reliability and generalisation of the results entails some uncertainty due to the number of dwellings and data points available.

All in all, it was found that the thermal sensation is correlated with the four comfort related factors (thermal preference, clothing, metabolic activity, action), the indoor air temperature as well as the energy labels and the ventilation types, while only age was resulted in not being associated with thermal sensation. Indoor air temperature was found to be related with the energy label of the dwellings, but not with their ventilation type. In addition, the results indicated that the heating energy use is related with the outdoor air temperature as well as with the indoor-outdoor air temperature difference, but not with the indoor air temperature. Energy labels and ventilation types were found to be related with the heating energy use, while thermal sensation, actions and income did not show any correlation with it.

Based on the findings it is concluded that the adaptive thermal comfort model is more accurate and closer to the reality of a residential environment in comparison with the steady-state PMV model, where no adaptations take place. However, it is highly recommended that instead of improving the existing thermal comfort models, personalised comfort models could be developed for each single person separately by gathering data using sensors. This would help to trace all different parameters that influence the thermal comfort and the energy use as well and lead to more accurate prediction and lower actual energy use.

Reduction of energy consumption is currently high on the political agenda of many
countries. Because buildings consume a significant amount of the total energy
consumption they form a big energy saving potential. For this reason the EPBD was
introduced. This directive introduced a mandatory energy performance certificate for all buildings in Europe (in the Netherlands implemented as energy label). The initial aim of this directive was to make people aware of the energy efficiency state of the building that they buy or rent.