This thesis presents the optimization of a quarter-wavelength tube (QWT) system for the absorption of low frequency sound in the range of 88 to 355 Hz. Low frequency noise, often generated by sources such as traffic, heavy machinery, and HVAC systems, present significant challenges in building acoustics due to the large material thickness required for absorption. This study proposes a compact, efficient, and customizable solution using quarter-wavelength tubes. These tubes can be connected with each other not only in series, but also in parallel. The configuration considered in this thesis is a combination of the two different combination types.

The goal of this research is twofold:
• To maximize the absorption of QWT systems in the aforementioned low frequency bandwidth.
• To minimize the volume of these QWT systems to improve the possibility of incorporating them into sound absorbing panels and to reduce the material use of the systems.

To achieve this, a methodology consisting of three different types of analysis is used.
• Analytical analysis: A Python code is designed for the optimization of the QWT system. This code consists of two parts: The part where the absorption coefficients of a QWT system is calculated using the recursive formulation, and the part where the dimensions and number of tubes of the system are optimized using the evolutionary algorithm DEAP. The most optimal system is used for the next analyses.
• Numerical analysis: Finite element analysis (FEA) was performed in COMSOL Multiphysics (in short: COMSOL), using both Pressure Acoustics physics with Narrow Region Acoustics and Thermoviscous Acoustics interfaces. These simulations provide more accurate absorption coefficient results than the analytical Python code, as three-dimensional thermoviscous effects are considered in more detail.
• Experimental analysis: Scaled prototypes were 3D printed using PLA and tested in an impedance tube to measure their real-world performance.

The final optimized QWT system using DEAP achieved broadband low frequency absorption while being significantly more compact than traditional absorbers. This system consists of one main tube connected in series to five parallel tubes. Optimization caused a decrease of 2731 cm3 of air volume in the QWT system, while the absorption coefficient only slightly decreased. Less air volume in the system means that the different QWTs can be smaller, so less material is needed.

The analytical and numerical results aligned very well, but the experimental results were slightly off. This may be caused by the lack of complete airtightness of the model or the presence of undissolved support material (PVA).

From an engineering perspective, this research showcases how QWT systems can be optimized to effectively absorb low frequencies. Different boundaries can be entered into the optimization code, which makes it possible to design an optimized QWT system for every situation. This is especially useful where space or thickness is limited for traditional sound absorption.

In conclusion, this thesis bridges theoretical acoustics, computational modelling, and practical engineering, resulting in a tunable, space-saving soundproofing solution that can be adapted for real-life application. Further research may include the application of different materials or testing such systems on a large scale.

This thesis explores the upcycling of post-consumer glass waste into functional acoustic panels for architectural applications. Addressing both environmental concerns and indoor acoustic performance, the research investigates the potential of glass foaming and fusing techniques to transform discarded glass, such as soda lime, light bulb glass, and mixed cullet, into porous, sound-absorbing elements suitable for use in the built environment.
The study begins with a comprehensive literature review on glass recycling, classification of glass waste streams, and limitations within current recycling infrastructures, particularly regarding contaminated or mixed glass cullet. The material science behind foam glass production is examined, with a focus on how porosity, pore size distribution, and pore interconnectivity affect acoustic absorption. Kiln-based secondary casting and fusing techniques are also reviewed as accessible, energy-efficient alternatives to primary glass forming processes. In parallel, the acoustic literature is reviewed to understand key performance indicators such as reverberation time, clarity index, and sound absorption coefficient, especially in relation to porous materials. Furthermore, the review introduces the growing use of computational tools in acoustic design, including the use of simulation environments (such as CATT-Acoustic) and parametric optimization workflows (e.g., in Grasshopper), which allow for data-driven decision-making in early-stage material and geometry development.
A series of experimental trials were conducted to evaluate how various glass types respond to foaming, with particular attention paid to their level of contamination. Variables such as foaming agent type (calcium carbonate, eggshells, manganese dioxide), glass composition, particle size, and firing schedule were tested for their influence on pore development and structural integrity. Glass was successfully foamed at 860°C and 790°C. Notably, eggshells showed strong compatibility not only with clean soda lime cullet, but also with more contaminated light bulb glass and mixed cullet, yielding homogeneous pore structures. Re-foaming tests and prototype casting using 3D-printed moulds demonstrated the adaptability and scalability of the method. Selected samples were tested using an impedance tube, confirming their ability to absorb mid- to high-frequency sound, particularly around 1000 Hz, a range critical to both music and speech. The highest absorption coefficients were achieved with soda lime glass; however, the presence of contamination in other glass types did not significantly diminish acoustic performance of the developed material.
To enhance mechanical integrity, fusing trials were conducted to bond the porous layer to a solid glass surface. This was done without compromising the internal pore structure, achieving successful fusion at 705°C for samples made of both light bulb and soda lime glass paired with soda lime float glass.
To evaluate architectural performance, the panels were applied in a digital acoustic simulation of a real-world case study: the 2200 m³ Theatre Hall at TU Delft. The space suffers from excessive early reflections and high clarity index values. Field measurements were used to calibrate a model in CATT-Acoustic, which then informed a parametric optimization process in Grasshopper to determine optimal panel placement. The strategy focused on reducing C80 while preserving reverberation time, maintaining suitability for both rehearsal and performance scenarios. Although improvements in acoustic metrics were modest, they demonstrated that the porous panels successfully reduced problematic reflections without overly damping the space.
Through the integration of material science, real-world measurement, computational acoustics, and parametric design and design optimization, this thesis presents a viable, circular strategy for converting low-value glass waste into functional acoustic components. The findings point to broader potential applications in performance spaces where a nuanced balance between clarity and reverberation is required, offering a solid foundation for further research into sustainable material acoustics.

By 2050, the Dutch construction sector is required to be fully circular, where bio-based materials can play a promising role in this transition. However, the implementation of bio-based materials is currently limited due to a lack of technical design knowledge within the sector. Additionally, the hygroscopic properties are insufficiently understood, which further hinders the integration of bio-based materials into building designs. The main objective of this thesis is therefore to develop validated 1:5 scale bio-based façade wall reference details for residential top-up buildings that perform well in reducing thermal bridges and ensuring effective moisture transport. The research combines a literature review with research-by-design and digital simulations. Initially, the advantages and disadvantages of bio-based construction materials over conventional ones are examined. Following this, five bio-based materials (cork, flax, hemp, straw, and wood) are selected and incorporated into the developed bio-based reference details. Design principles were first established to ensure the correct implementation of these materials. In total, this thesis presents 11 detail configurations, consisting of 33 validated bio-based reference details. These details were evaluated using the simulation software WUFI for moisture transport, mould growth, surface condensation, and thermal bridges. The thesis outlines both the methodology and the results. The first configuration is discussed in detail in the main report, while the remaining ten validated configurations are included in the appendix. In addition, this thesis presents 33 additional reference details which were not validated but are expected to show similar performance to the validated ones. Based on the simulation results, most of the detail configurations meet the requirements for moisture regulation and thermal performance. The isopleth analyses indicate that mould growth does not occur within the tested material layers in most configurations. Furthermore, no surface condensation was observed at the most critical points within the details. The results also comply with Dutch regulations regarding limited thermal bridging, with the measured values comparable to those of the ‘ISSO reference details’. These simulation results hereby demonstrate that the developed bio-based reference details can be effectively used in residential top-up buildings. However, the established design principles and vapour permeability must be maintained. When applied correctly, the selected bio-based materials can prevent mould growth and surface condensation, while keeping thermal bridging to a minimum. Although the simulations provide valuable insights, the validation is limited by the exclusive use of WUFI. Next, only a medium moisture load for indoor climates and the NEN 5060 for outdoor climates are used making the assessments only representative for the Netherlands. Future research could validate the results using alternative simulation software and by considering various climatic and moisture conditions. Before the developed details can be applied in the Dutch market, additional research must explore the remaining building physics aspects and structural requirements. Nevertheless, the developed design principles and validated reference details provide a solid foundation for the further implementation of bio-based construction in Dutch residential buildings.

Modern wall systems are constructed by overlayering toxic, petrochemical materials. Hempcrete can replace this complex stack as a monolithic wall that serves structure, insulation, moisture buffering, acoustic damping and fire resistance in one single material. Hemp shiv and a lime binder form a self-supporting mass whose performance depends parameters like density, compaction methods, binder-to-hemp ratio and shiv orientation. Under a 75% end-of-life recycling scenario, hempcrete removes a net 14 kg CO2-equivalent per functional unit from the atmosphere, making it a carbon-negative building material. Field observation on a full-scale hempcrete wall show that the manufacturing workflow is still artisanal, subjective and weather-dependent, leading to high labour demands and unreliable wall performance.

This research aims to produce a self-standing and insulating hempcrete wall with predictable performance. An experiment is set up, varying manufacturing parameters: layer height, compaction factor, orientation and binder type. Layers thinner than 10cm and compaction above 50% prevented interlayer density gradients, preserving hygrothermal properties and providing a safe mechanical margin. Top-down compaction increased compressive strength exponentially, but showed big settlement. Monolithic hempcrete still needs extra stability. Strategies proposed in this research include altering mix design, section geometry or integrating natural reinforcements. However, life-cycle recalculations show a carbon-neutral ceiling: further increasing density, binder ratio or wall thickness should be done with care, to keep the overall emissions net-negative.

This thesis presents an innovative façade element designed to significantly reduce a building’s operational energy consumption while ensuring full recyclability. It achieves this by dynamically adjusting the thermal insulation of a mono-material facade element.
Given the building sector’s high global energy consumption and waste production, such innovations are critically needed.

The methodology consists of a literature review followed by three design phases: (1) conceptual design; (2) preliminary design; (3) final design. The iterative build–measure–learn cycle guided the development process.

Four different designs were developed for the switchable insulation: auxetic structure, soft robotics, doors and organic tree. The auxetic structure was selected to be further developed because of its low sensitivity to production errors and high thermal performance in the insulating state.

When it comes to the material, thermoplastic copolymer (TPC) was used for the facade, because of its flexibility, flame retardance, UV and moisture durability, compatibility with 3D printing, recyclability, and adherence to ISO and EU standards.

The final design achieves a Rc-value of 4.7 m²K/W in its insulating state and 1.16 m²K/W in its conducting state. Switching the state is done with a pneumatic actuator controlled by a rule-based system, making the facade responsive to its environment.

Future research should focus on optimizing the auxetic structure to reduce actuation force and exploring alternative sustainable materials compatible with the mono-material switching concept.

Recent geopolitical events have driven a sharp rise in gas prices, making it increasingly difficult for households to heat their homes affordably and comfortably. Additionally, the environmental consequences of fossil fuel-based heating underscore the urgency of transitioning to more sustainable alternatives. In response, the Dutch government has set an ambitious target to eliminate natural gas heating in 1.5 million homes by 2030, emphasising the need for viable solutions. District heating (DH) systems, particularly those providing lower-temperature heating (LTH), offer a promising alternative—delivering sustainable and cost-effective heating, especially in densely populated areas. However, with their high heating demands, many existing homes require significant renovations before efficiently transitioning to LTH-based systems. The selection of appropriate renovation strategies is complex, often leading to uncertainty and delays. This research tackles the challenge of preparing Dutch homes for LTH by developing a systematic decision-support framework using a mixed-methods research approach. It is structured around four key research activities. First, it identifies and analyses the critical factors influencing building characteristics, available renovation options and performance indicators. Second, it defines LTH readiness, prioritises thermal comfort and energy efficiency at reduced supply temperatures, and uses a two-step evaluation method to assess a dwelling's readiness and identify necessary interventions. Third, recognising the diversity within the Dutch housing stock, probabilistic sampling and machine learning analyses were employed to quantify the relative significance of building features affecting LTH readiness, accounting for variations across dwelling types. Finally, a structured six-step decision support framework based on multi-criteria decision-making (MCDM) methods was developed and validated through real-world case studies and stakeholder workshops. By providing a clear and actionable decision-support framework, this thesis facilitates energy renovation planning, accelerates the transition to gas-free heating, and contributes to the Netherlands' broader sustainable energy goals.

This thesis investigates the performance of inkjet-printed electrochromic (EC) glass compared to traditional triple glazing with roller shades in an office setting in the Netherlands. The study aims to assess thermal and visual comfort, via a live experiment conducted in a controlled environment. Key performance indicators (KPIs) include thermal sensation & preference, solar heat perception & satisfaction, (day)light adequacy, colour rendering satisfaction, view clarity satisfaction, and glare perception. Results indicate that EC glass outperforms traditional glazing in maintaining thermal comfort, particularly in darker scenarios, although both glazing types keeping room temperatures within a comfortable range. Visual comfort results are mixed; EC glass provided better daylight sufficiency in low-light conditions, while traditional glazing offered better performance in bright conditions. User satisfaction regarding colour rendering and glare did not show significant differences between the two façade types. This study was limited to the winter period of the Dutch climate. Ideally, to obtain a complete picture of the performance between both facades, this experiment should be conducted again during the summer period or in a warmer climate.

Despite its importance to public health, environmental noise and soundscapes are a forgotten topic in urban design. This study crates a framework for a design tool for soundscape design. The aim of this framework is to bridge the knowledge gap of soundscapes for urban designers. This is done by looking at the relationship between design elements and the percevied pleasantness in the soundscape. This pleasantness will be predicted by machine learning methods.
Machine learning methodologies present a promising approach for predicting and evaluating the efficacy of potential solutions aimed at improving urban soundscapes. By analyzing datasets that include environmental factors, noise levels, architectural designs, and community preferences, machine learning algorithms can help identify optimal interventions. Predictive models can also streamline decision-making processes by forecasting the potential impact of proposed solutions on soundscape quality.
This paper investigates the complexities of urban soundscapes, examines the feasibility and limitations of using machine learning to predict viable solutions, and proposes a data-driven framework to guide decision-making in urban development. The goal is to enhance auditory environments in urban areas without the necessity of consulting soundscape experts.
The RF regressor that was used for the prediction model in this research had an R2 of 0.41, explaining 41% of the variance of the model. This framework is tried and tested on a new location to verify its use. The prediction maps and section are a helpful tool in communicating the value of the soundscape pleasantness and understanding the effect that the design elements have on its prediction.

The growing threat of climate change highlights the necessity for long-term solutions in the construction industry. Buildings account for a large share of worldwide energy consumption and carbon dioxide emissions, so there is an urgent need for creative techniques to improve energy efficiency and reduce their ecological footprint. This thesis focuses on this by creating a computational optimization workflow for incorporating hempcrete, a low-carbon construction material, into high-performance structures during the initial stages of design. This approach uses a multi-objective optimization process to offer optimal solutions adapted to various climates and building types, optimizing energy efficiency and daylight while limiting global warming potential. Architects and engineers can get greater performance and sustainability results by experimenting with different layout options and design parameters using parametric modelling, energy analysis, and optimization algorithms. The suggested workflow provides a systematic technique to facilitate decision-making during the key design steps, promoting hempcrete implementation and accelerating the shift to performance-driven architectural design in response to climate change problems.

Architecture is much more than just built forms on a piece of land. Architecture hinges on user experience and comfort. As such, it is up to us, as designers and engineers to be mindful of the quality of the conceptualized space.

Building physics is one such field that addresses the concerns of users. It outlines topics that play an integral role in the quality of life; thermal comfort, ventilation, lighting, and acoustics. The first three factors have something in common. They have evolved and been developed to the point where the user has the luxury of controlling this factors at a scale local to the user itself. This creates an enhanced user experience. Acoustics, on the other hand, poses numerous problems when the topic of personal control is broached. There are many factors that impact the quality of sound in a space. That is, there are simply too many variables one must take into account while addressing the topic of personalised control of sound in a room. Acoustic control systems, while existent, heavily hinge on the usage of technology to provide user control, resulting in bulky or expensive systems that makes this very concept of personalised control a distant reach to the average user.

Schools, particularly primary schools and middle schools pose an interesting challenge. In addition to the varying functions that happen in a classroom over the span of a day or a lesson plan, the users also have differing sound demands. Teachers’ main concern is related to vocal strain and fatigue, while the poor acoustic conditions affect students’ learning and social development.

While acoustic standards are largely enforced in the built environment during and post construction, it is imperative that we acknowledge that these standards are set for adults, by adults. They are values that make sense to a person with fully developed auditory and sensory systems. They are limited by the general function of a space and do not necessarily address the nuances of spatial usage. As a result, applying these standards as an unwavering rule to architectural typologies aimed at children might not be the most ideal approach. The still developing auditory and sensory systems of children, and the resulting requirements must be taken into account in spaces aimed at them.

This thesis aims to explore the possibilities that passive (dynamic) systems offer in the realm of acoustic and sound control set in the context of a middle school classroom. This process is done by theoretical calculations and digital simulations.

Global warming is causing more extreme weathers leading to floods, inundation, high temperatures and increasing of cooling demands. More resilient homes and mitigation of CO2 emissions are needed. This thesis aims to investigate the integration of passive cooling to adaptive flood-resistant homes. The popular stilts houses located in the Mekong Delta are being analyzed: a vernacular home developed by the inhabitants that aims to cope with the local climate and floods. Multiple researchers concluded that improvements need to be made to cope with overheating in homes and for more dangerous floods in the future. According to literature review designs that incorporate insulation, natural ventilation, (moveable) shading and operable windows are the best methods for passive cooling of buildings in humid climates. Amphibious structures enable buildings to adapt to the changing water levels but staying fixed to one place. Simulations demonstrate that transforming a traditional stilt house into a flood-resistant amphibious home can reduce the operative temperature by a maximum of 1 degree Celsius. Integrating insulation in the walls and roof, along with an insulated tropical roof and floor vents, can lead to a maximum temperature reduction of 4 degrees Celsius. As a result; lower indoor temperature, adaptive flood-resistance and reduced energy demand for cooling. Further research and attention is needed to make designing for homes related to flood circumstances more accurate and find more of an approach that lives with water instead of fleeing from it.

The building sector significantly impacts the environment, consuming 42% of the EU's energy and producing 36% of its greenhouse gas emissions. To achieve its climate objectives, the Netherlands must accelerate its home renovation rate to 200,000 annually by 2030. This research addresses the scalability and circularity of façade renovation for these system-built houses, aiming to balance immediate energy efficiency improvements with long-term sustainability.
This research focuses on designing a scalable and circular façade renovation system for post-war Dutch system-built houses. These homes, built between 1945 and 1975, represent around 30% of the Dutch housing stock and are in critical need of energy efficiency upgrades. However, the embodied energy involved in renovations presents a significant challenge to meeting climate goals. The study's primary focus is answering: "How can a scalable and circular façade renovation system be designed for Dutch system-built houses from the post-war period?" The research investigates current façade renovation systems, their limitations, and the potential role of circularity in creating sustainable renovation strategies. It also examines building typologies, highlighting similarities and differences among system-built houses to develop design criteria for scalable and circular renovation. Although time constraints prevented the development of a complete design, the research reveals that many existing façade components, such as brick slip systems and prefabricated frames, already perform well. However, achieving flexibility and scalability remains challenging, particularly in balancing cost, energy efficiency, and building-specific constraints. This work lays the groundwork for future research into developing standardized, adaptable façade renovation systems for the Dutch housing stock, contributing to more sustainable and efficient building practices while addressing the challenges posed by post-war system-built houses.

The study is motivated by the abandonment of vernacular architecture in rural tropics, which has led to greater energy demand due to the higher embodied energy of construction materials and increased use of air conditioning. This research examines how and to what extent bioclimatic strategies in vernacular architecture of dwellings in a tropical monsoon climate can improve thermal comfort. A mixed-methods approach is used, including a qualitative analysis of three vernacular case-study examples and a quantitative simulation of the thermal performance of the three vernacular dwelling compared to a non-vernacular dwelling. Results show that bioclimatic strategies in vernacular architecture are highly dictated by the dominant characteristics of the climate, with a focus on solar shading, natural ventilation, and discharge of rainwater. The simulation results indicate that the non-vernacular building performs poorly in managing heat gain, with thermal comfort only reached in 56.7%, 56.3%, and 53.9% of the simulated instances. The vernacular building performs better than the non-building scenario in most cases, with the exception of Kerala. The study also found that the hourly and monthly plot of operative temperature and relative humidity of the three scenarios do not show any diurnal or seasonal differences from the effects concluded in the psychrometric charts. This is attributed to the tropical monsoon climate, which does not have distinct seasons or diurnal differences in temperature and can be considered quite constant. The research highlights the importance of considering the unique characteristics of a specific climate when

The rise in average surface temperature has intensified the need to explore new
methods to address climate change. Housing sector is one of the leading contributors to the total energy consumption. As a solution, there has been a growing emphasis on the application of passive strategies in buildings that leverage local climatic conditions.

Researchers have been investigating solutions to promote the use of passive design strategies. One promising approach involves integrating Phase Change Materials (PCMs) with certain building components. By possessing excellent thermal and optical properties, PCMs can be integrated into windows to enhance the thermal performance of buildings while guaranteeing light transmittance.

This research specifically focuses on the integration of PCMs trombe walls in
existing residential buildings in the Netherlands. Building upon the findings of
previous studies, the research envisions to explore strategies that can facilitate
the widespread use of PCMs. Currently, the market for PCMs primarily offers
products manufactured on request, limiting their broader adoption.

Through simulations conducted on virtual models, the behaviour of PCMs in
trombe walls is investigated. The analysis focuses their thermal capacity and
light transmittance to strike a balance between the two contrasting building requirements. Multiple room configurations are studied to investigate how the environment impacts the performance of this particular building component.

Finally, the research develops a workflow and identifies trends that can facilitate
the application of PCMs trombe walls across various scenarios.

This report investigates the potential use of Phase Change Material (PCM) technology in poorly insulated lightweight homes in the Netherlands. The aim is to develop a cost-effective and easy-to-install PCM product that can decrease energy consumption through passive heating and cooling. The proposed design involves a multi-layer curtain system with small PET macroencapsulations containing salt hydrate attached to a sheer curtain. The system also includes a secondary insulation layer made of polyester with a reflective aluminum lining as a thermal barrier. MATLAB simulations indicate that this system, with 16 liters of PCM, can reduce heating loads by 7-9% when applied to a living room bay window measuring 4.46 m2 within a 28.8 m2 room. However, the insulation layer provides the most significant heat loss reduction. The simulation results also demonstrate a lower average summer temperature when the insulation curtain is not applied, suggesting effectiveness in both summer and winter. The estimated payback period for the system, based on the Dutch gas price cap of
€1.45 per m³, is 5 - 8.5 years. The report concludes that while the proposed PCM system has the potential to reduce energy usage in lightweight homes, further research is necessary to determine its actual effectiveness.

A master thesis what researched the visualization of phase change materials (PCMs) with augmented reality (AR) for different 3 different user groups. The user groups are researchers, maintenance and customers. The research question is "How does AR contribute to the understanding of the behavior of PCM for science, maintenance and customer groups?". With simulations in Comsol and an experiment the AR possibilities were validated. The AR gave insight in the behavior of PCM and was applicable for each group.

The world is in a climatic crisis. Extreme weather events are stronger and more frequent than ever before, exacerbated by human induced CO2 from energy production and the built environment. Only 5% of world energy is produced by renewable energy sources, presenting an enormous gap between sustainability and greenhouse gas emitting practices. Pledges and agreements aim to curb world emissions through net zero energy buildings and increasing the amount of energy produced by renewable resources. When considering the ‘Energy Hierarchy Pyramid’ the first step is to reduce energy consumption, the second is focused on energy efficiency and the third is focused on renewable energy sources. Computers allow for energy simulations to estimate building operations and their efficiency, aiming to curb energy use during building operation phases. Methods exist, knowledge exists but more often than not the application of such simulations is applied later rather than sooner.

When site and climate are known there are specific design strategies which can be implemented to reduce energy consumption. Passive strategies such as windcatchers, trombe walls, roof ponds, sunshading, sun spaces or solar chimneys are not climate dependent. Their properties, however, change depending on the climate type they inhabit. Design factors such as volume, fenestration characteristic and material choice have an impact on energy consumption and are design decisions taken in early design stages.

Energy simulations have the possibility to inform early in the design stage. This thesis focuses on an optimization workflow which generates and stores simulation data throughout each design step segregating: volume, fenestration, materials and passive strategy integration. The workflow is separated into two potential paths; multi-objective comparison, focusing on comparing design option with other self-defined design options and multi-objective optimization, centered around running genome optimizations through Grasshopper’s Wallacei, minimizing or maximizing fitness values.

The workflow aims at developing knowledge throughout the design process, balancing qualitative and quantitative data to generate a data-informed design. A multi-objective approach strengthens the decision making process and presents the trade-offs required to obtain the design improvement. Ultimately, design is a conscious decision. Expanding knowledge will serve to guide and inform but never to define a design. Reducing energy consumption is a design choice and comprehending the design alternatives will flourish possibilities towards a more energy conscious future.

The built environment contributes in a large extend to the global greenhouse gas emissions. With a growing demand for new buildings another view on building products is required. This thesis focusses on creating a biobased sound absorbing panel made from a mycelium bound biomaterial derived from urban waste. The production method for this panel is 3D printing, since with this production method changing demands can be met.

In this thesis six experiments are executed regarding the development of a printable material from urban waste, the sound absorbing properties of the designed panel and 3D printing. To create a printable paste from urban waste, a couple of urban waste materials have been reviewed. Brewery’s grain came out as the most promising growth medium for mycelium. This material is mixed with flour and water to create a printable paste.

The impedance tube B&K 4206 is used to discover the acoustic properties. For the 3D printing a UR5 robot in combination with a LDM WASP extruder 3.0 XL is used. To control the robot movement, Rhino with Grasshopper in combination with the plug-in Robots is used. For understanding the acoustic behavior of the panels, multiple variables regarding printing and design parameters have been tested.

The final product of this research is a 3D printed panel which can be made with a mixture of brewery’s grain, all-purposes flour, water, and mycelium from the Pleurotus.

Acoustics combined with digital fabrication has been investigated for multiple years. Most research in this area has focused on the combination of acoustics and additive manufacturing. This is mainly due to the ability of this technique to create any geometry, which allows for very high absorption. However, it has the downside that additive manufacturing is quite expensive and the production process is time-consuming. Therefore, this study has chosen to put the geometry first and the performance of the resonators second.
To be able to produce a resonant panel based on Helmholtz resonators some additional knowledge was needed. Therefore, five experiments were performed to gain the knowledge needed to design the panel. The samples were printed using a fused filament printer and tested within an impedance tube located at the Faculty of Architecture in Delft. The experiments were concerned with:
- The position of the neck compared to the cavity: According to the results of the experiments the position of the neck has a minimal to no effect on the performance of the resonator.
- The crosstalk effect: According to the results of the experiments the effect of the crosstalk effect is minimal within the scope of this project. A small change in absorption was noticeable but so small as to be irrelevant.
- The effect of the cavity separation between two resonators: According to the results of the experiments the cavity separation can be removed without a large effect on the absorption of the resonators.
- The effect of the neck length on the width of the absorption curve: According to the results of the experiments a longer neck causes the width of the absorption curve to decrease.
- The impedance of resonators with L-shaped cavities: According to the results of the experiments an L-shaped cavity can be approximated by replacing the L-shaped cavity by a cavity with an identical horizontal section right below the orifice but altering the height, so the cavity has the same volume as the original L-shaped cavity.
After the experiments were done, a computational workflow was designed that is able to produce resonant panels based on the targeted frequency range and the possible size of the panel. The tool was theoretically verified using a case study. For the case study two panels were designed to improve the reverberation time for a room in the Faculty of Architecture. Using the Arau-Puchades method of calculating the reverberation time the panels showed to be effective at absorbing sound at low frequencies.

The anthropogenic demand for food, energy and water (FEW) resources is growing, changing and increasingly concentrating in cities due fast urbanisation worldwide. Carbon dioxide emissions associated with the FEW supply infrastructure makes cities one of the main drivers of global greenhouse gas emissions. Urban food production (UFP) could potentially mitigate city’s carbon emissions by means of direct and indirect emissions cutbacks, respectively through proximity based advantages and recirculation benefits by integration with the urban resource infrastructure. The inherent complexity and comprehensiveness of food production makes it challenging to explore this method during the urban design process and provide holistic evaluations at an early stage.

This research investigates how urbanising the production of food can mitigate the carbon emissions of urban communities. Along the principles of the FEW nexus approach to resource management, a method and platform have been developed that support professionals such as urban planners and designers with the exploration of urban food production in the design process. The aim of this work is to transform cities into more sustainable and resilient places to live. This work hypothesises that urbanising the production of food resources and making urban food production an integral part of the urban resources infrastructure can help the decarbonisation of cities. The objective of this work is to develop a protocol and platform for a non-expert, multi-disciplinary urban design team that can guide the implementation and evaluation of a food production system. The platform, which has been coined the FEWprint, should guide the agro-urban designer during the exploration phase of the design process by providing quantitative feedback on various relevant indicators. The following main research question has been formulated based on the problem statement, hypothesis, research aim and objective: How could the urban food production design process be harmonised with the FEW nexus principles in order to lower the carbon footprint of the city?...