| 1. |
- Mathern, Alexandre, 1986
(författare)
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Addressing the complexity of sustainability-driven structural design: Computational design, optimization, and decision making
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Being one of the sectors with the largest environmental burden and high socio-economic impacts sets high requirements on the construction industry. At the same time, this provides the sector with great opportunities to contribute to the globally pursued sustainability transition. To cope with the increasing need for infrastructure and, at the same time, limit their sustainability impacts, changes and innovation in the construction sector are required. The greatest possibility to limit the sustainability impact of construction works is at the early design phase of construction projects, as many of the choices influencing sustainability are made at that point. Traditionally, an early choice of a preferred design is often made based on limited knowledge and past experience, considering only a handful of options. This preferred design is then taken on to the successive stages in the stepwise design process, leading to suboptimization. Alternatively, many different design choices could be considered and evaluated in a more holistic approach in order to find the most sustainable design for a particular application. However, finding design solutions that offer the best sustainability performance and fulfil all structural, performance and buildability requirements, require methods that allow considering different design options, analysing them, and assessing their sustainability. The aim of this thesis is to explore and develop methods enabling structural engineers to take sustainability objectives into account in the design of structures. Throughout this thesis, a number of methods have been explored to take sustainability aspects into account in the structural design process. As a first step, highly parameterized computer codes for sustainability-driven design have been developed. These codes interoperate with FE analysis software to automatically model and analyse design concepts over the whole design space and verify compliance with structural design standards. The codes were complemented with a harmonized method for life cycle sustainability performance assessment, in line with the state-of-the-art standards. Here, sustainability criteria were defined covering environmental, social, economic, buildability and structural performance for multi-criteria assessment of design concepts. To identify the most sustainable designs within the set, multi-objective optimization algorithms were used. Algorithms that address the high expense of constraint function evaluations of structural design problems were developed and integrated in the parameterized computer codes for sustainability-driven design. To ensure the applicability and validity of these methods, case studies based on real-world projects and common structural engineering problems were used in this thesis. Case studies for bridges and wind turbine foundations as well as a benchmark case of a reinforced concrete beam were investigated. The case studies highlight the potential of the methods explored to support the design of more sustainable structures, as well as the applicability of the methods in structural engineering practice. It is concluded that it is possible and beneficial to combine computational design, life cycle sustainability assessment, and multi-objective design optimization as a basis for decision making in the design phase of civil engineering projects. A wide adoption of such a sustainability-driven design optimization approach in structural engineering practice can directly improve the sustainability of the construction sector.
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| 2. |
- Shadram, Farshid, 1987-
(författare)
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Assessment and optimization of life cycle enrgy use in buildings
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Buildings account for 40% of all energy use in European countries. The European Union (EU) therefore encourages member states to adopt Energy Efficiency Measures (EEMs) and implement energy-efficient practices during building design to minimize the energy use of buildings. However, recent studies have shown that energy-efficient buildings may not always outperform conventional buildings in terms of Life Cycle Energy (LCE) use. This is mainly due to the trade-off between embodied and operational energy, and a reliance on EEMs that reduce operational energy while sometimes increasing embodied energy and LCE use. To improve buildings’ environmental performance, the impact of different EEMs on buildings’ energy use needs to be assessed from a lifecycle perspective, and methods for identifying optimal combinations of EEMs that minimize LCE use should be developed. Ideally, these methods should be integrated with building information modelling (BIM) to enable seamless data exchange and to help Architecture, Engineering and Construction (AEC) practitioners make optimal design decisions relating to EEMs. The work presented in this thesis had two overall objectives: (1) to explore the scope for developing BIM-supported method(s) for assessing and optimizing the impact of EEMs on buildings’ LCE use during the design process, and (2) use the BIM-supported method(s) for exploring the impact of various EEMs that are implemented and modified during the building design process on the buildings’ LCE use.The work presented in this thesis is based on an exploratory research design involving iterative cycles of (1) problem identification, (2) method development, (3) method examination, and (4) theory suggestion. In step 1, problems were identified by conducting literature studies and workshops with AEC practitioners, and analyzing archival data. In step 2, prototyping was used to develop methods to overcome the identified problems. In step 3, the applicability of these methods (or prototypes) was tested in case studies on actual and hypothetical building projects. Three case studies were conducted – one dealing with a low energy dwelling located in Kiruna, Sweden; another dealing with a multifamily residential building in Uppsala, Sweden; and a third dealing with a hypothetical multifamily residential building in Stockholm, Sweden. In step 4, the results were compared to existing theories to strengthen existing knowledge and identify previously unrecognized findings.In relation to the first objective, the results obtained show that the factors and activities required to develop BIM-supported method(s) for assessing and optimizing the impact of EEMs on a building’s LCE use during the design phase are:• A database that stores external and building project data (e.g. BIM data) and links it to be used for assessment and optimization, providing access to the data whenever needed.• The development of interfaces using middleware applications to ensure interoperability and seamless automated exchange of information between BIM and other systems.• Predefined objects (i.e. building part and component recipes) that are stored in a database and linked to inventories and Environmental Product Declarations (EPDs) for the relevant materials, enabling assessment of the buildings’ embodied energy and LCE use.• The application of multi-objective optimization techniques (e.g. Pareto-based genetic algorithms) to identify optimal solution(s) for EEMs that minimize (optimize) the building’s LCE use.In relation to the second objective of the thesis, the results obtained indicate that:• EEMs that are implemented and modified during the detailed design phase have much less influence on the building’s LCE use than those implemented in the early design phase. Highly influential EEMs related to the early design phase which were tested herein were the building’s shape, orientation, Window to Wall Ratio (WWR), and the selection of materials used in the building envelope.• Generally, thickening roof insulation has a strong beneficial effect on LCE use for buildings in Sweden.• For buildings using energy sources with high primary energy factors, the most effective way to reduce LCE use may be to implement many EEMs that reduce operational energy use. However, this approach may be less helpful for buildings using greener energy sources because in such cases the embodied energy may have a greater effect on the final LCE use.• The embodied energies of materials in the same class can vary significantly between suppliers. Such differences in embodied energy can be identified by considering the suppliers’ EPDs, the energetic contributions due to their mode of transportation from the site of production, and the distance between the site of production and the construction site.• If the developed optimization approach is used to identify optimal combinations of EEMs in the early design phase, designers can freely choose from a wide range of building shapes without greatly affecting LCE use. However, without early phase optimization, designs that use different building shapes may exhibit significantly different LCE use values.The results provide both theoretical and practical contributions that may be useful to researchers and AEC practitioners seeking to develop BIM-supported design processes and to reduce buildings’ LCE use by adopting appropriate EEMs. The results also show that embodied energy can be a major component of a building’s LCE use if the building’s design relies heavily on EEMs designed solely to reduce operational energy use. Policy makers and governmental bodies are thus advised to update regulations and building codes to reflect the importance of embodied energy so as to minimize the LCE use of new and retrofitting building projects.
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| 3. |
- Nägeli, Claudio, 1987
(författare)
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Bottom-Up Modeling of Building Stock Dynamics - Investigating the Effect of Policy and Decisions on the Distribution of Energy and Climate Impacts in Building Stocks over Time
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In Europe, residential and commercial buildings are directly and indirectly responsible for approximately 30–40% of the overall energy demand and emitted greenhouse gas (GHG) emissions. A large share of these buildings was erected before minimum energy-efficiency standards were implemented and are therefore not energy- or carbon-efficient. Consequently, buildings offer significant potential in terms of energy efficiency and the reduction of GHG emissions compared to the status quo. To make use of this potential at scale, targeted policy measures and strategies are needed that should be based on a quantitative assessment of the feasibility and impact of these measures. Building stock models (BSMs) have long been used to assess the current and future energy demand and GHG emissions of building stocks. Most common BSMs characterize the building stock through the use of archetype buildings, which are taken to be representative of large segments of the stock. The increasing availability of disaggregated datasets—such as building registries, 3D city models, and energy performance certificates—has given rise to building-specific BSMs focusing on describing the status quo as an input to energy planning, primarily on the urban scale. Owing to the availability of building-level data, BSMs can be extended beyond policy advice and urban planning, to the assessment of large building portfolios. Thus far, the advances made in building-specific BSMs on the urban scale have not been transferred to the national scale, where such datasets are often not available. Moreover, the focus on an increasingly detailed description of the existing stock has left approaches for modeling stock dynamics without much development. Stock dynamics, therefore, are still primarily modeled through exogenously defined retrofit, demolition, and new construction rates. This limits the applicability and reliability of model results, as the influence of economic, environmental, or policy factors on stock development is not considered. This thesis addresses these shortcomings and advances modeling practices in BSMs. The thesis with appended papers provides a methodology for how the modeling of national building stock can be further developed in terms of building stock characterization through synthetic building stocks as well as stock dynamics through the use of agent-based modeling. Furthermore, the thesis extends BSM applications to inform the strategic planning of large building portfolios through the integration of a maintenance and renovation scheduling method to project the future development of building portfolios.
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| 4. |
- Amiryarahmadi, Nata
(författare)
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A Virtual Design Studio for Low-Frequency Sound from Walking in Lightweight Buildings
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In recent years there has been a growing interest for building lightweight multistorey woodenresidential buildings in countries like Sweden with large and renewable forests. While positive aspectsof these buildings, such as sustainability, ease of construction and lightness, motivate building more inwood, poor acoustic performance is a risk which concerns the wooden-building industry.Low-frequency impact sound from walking of the neighbors upstairs is the main source of complaintsabout the acoustic performance of these buildings. The disturbance caused by walking sounds,transmitted through lightweight wooden floors, results in acoustic discomfort and impairs theperceived quality of the building; sometimes even when the building has fulfilled an acoustic classhigher than minimum requirement, according to the national standard on sound classification and itssingle number ratings. The standard methods for objective evaluation of impact sound insulation offloors cannot predict, at a satisfactory level, the walking sound annoyance that the inhabitants ofwooden buildings experience. This causes an uncertainty about the resulting perceived quality of thesebuildings, which greatly concerns the building manufacturers and demotivates them from choosinglightweight wooden elements over heavyweight building materials such as concrete. This uncertaintycan be overcome by evaluating the perceived acoustic quality of the building prior to its construction.One solution is to build test houses where the subjective acoustic performance of floor samples can beevaluated in advance to the building construction. However, building a test house is expensive;besides, for evaluating the effect of every design modification on the experienced acoustic comfort ofthe building, a real floor sample has to be built and installed in the house, which would be timeconsumingand costly. An alternative solution is to use virtual acoustic test facilities.In this thesis a virtual design studio for impact sound is developed. It is a tool that facilitates creatingand listening to the acoustic field generated by impact forces such as footsteps on lightweight floors. Italso provides the possibility to evaluate the acoustic performance of floor elements in an early designphase, and to investigate the correlation between design parameters and the perceived impact soundinsulation of the floor. The tool is demonstrated and a very first listening test shows that one can obtainresults which are in good agreement with the results in literature. Loudness, reverberation andthumping are shown to influence the annoyance. It is also shown that there is a difference in judgementof walking sounds by persons who have experience with lightweight floors at home and by those whodo not have that experience.
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| 5. |
- Danielski, Itai, 1973-
(författare)
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Energy performance of residential buildings : projecting, monitoring and evaluating
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Energy security and climate change mitigation have been discussed in Sweden since the oil crisis in the 1970s. Sweden has since then increased its share of renewable energy resources to reach the highest level among the EU member states, but is still among the countries with the highest primary energy use per capita. Not least because of that, increasing energy efficiency is important and it is part of the Swedish long term environmental objectives. Large potential for improving energy efficiency can be found in the building sector, mainly in the existing building stock but also in new constructions.Buildings hold high costs for construction, service and maintenance. Still, their energy efficiency and thermal performance are rarely validated after construction or renovation. As energy efficiency become an important aspects in building design there is a need for accurate tools for assessing the energy performance both before and after building construction. In this thesis criteria for energy efficiency in new residential buildings are studied. Several building design aspects are discussed with regards to final energy efficiency, energy supply-demand interactions and social aspects. The results of this thesis are based on energy modelling, energy measurements and one questionnaire survey. Several existing residential buildings were used as case studies.The results show that pre-occupancy calculations of specific final energy demand in residential buildings is too rough an indicator to explicitly steer towards lower final energy use in the building sector. Even post occupancy monitoring of specific final energy demand does not always provide a representative image of the energy efficiency of buildings and may result with large variation among buildings with similar thermal efficiency. A post occupancy method of assessing thermal efficiency of building fabrics using thermography is presented. The thermal efficiency of buildings can be increased by design with low shape factor. The shape factor was found to have a significant effect on the final energy demand of buildings and on the use of primary energy. In Nordic climates, atria in multi-storey apartment buildings is a design that have a potential to increase both energy efficiency (by lower shape factor) and enhance social interactions among the occupants.
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| 6. |
- Franzén, Anders, 1965
(författare)
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Skiftenas skede: laga skiftets handlingar som källmaterial för byggnadshistoriska studier med exempel från Småland 1828-1927
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis evaluates the archive records created in connection with the Swedish agricultural reform known as the Laga Skifte, the legislation for which was in force between 1828 and 1927. That legislation applied to the greater part of the country, but the analytical areas for the present these are located in the province of Småland. My main purpose is to investigate whether, and if so how, Laga Skifte documents can provide new information for settlement history research. In particular, over and above a basic source-critical discussion of the nature and reliability of the material, my interest focuses on two areas. Firstly, I analyse the different types of information which can be extracted from the source material, focusing on buildings and building. In this context the source character of Laga Skifte documents is discussed in relation to the character of other sources. Secondly, I explore the ability of the source material to shed light on relocations resulting from the Laga Skifte. The study is above all concerned with two questions, namely which households were obliged to move and which agents played a part in the work which relocation involved. Three case studies are presented, by way of testing the reliability of the Laga Skifte records as a historical source. Very often the data in the different sources concur, and I take this to mean that the Laga Skifte records contain reliable information. In certain cases, though, this congruence is lacking. When the sources do not provide similar data, I class this as omissions, inconsistencies or contradictions. I also examine the feasibility of using Laga Skifte records as a principal source for studies in vernacular architecture. A broad picture of the history of farm buildings is given, based on the Laga Skifte records. Each area of analysis is studied separately to begin with, using the building categories occurring on the farms. The investigation ends with two summaries. One of them is a synthesis of settlement, contrasting the characters of the different areas of analysis. The province of Småland, which has previously been portrayed as fairly uniform, turns out to include many different types of settlement. The second summary is a concrete comparison with previous research, and through this the potentialities and weaknesses of the Laga Skifte records can be made clear. One chapter considers the information obtainable from the Laga Skifte records as to which households are relocated on account of the Laga Skifte and which agents take part in the relocations. Previous research argues that small farmers with poor buildings had to move out of the hamlets in connection with the Laga Skifte. My studies show that this was commonly the case but that there were many exceptions. I open my discussion of who participated in relocations by considering the concept of day-works. Basically, they can be divided up into skilled day-works, done by professional craftsmen, and less skilled day-works which could be performed by the common man. Generally speaking, I conclude from the relocation costing estimates that unskilled day-works predominate in the early, pre-1850 redistributions, but that bricklayer day-works also occur. Bricklayers took part in the construction of chimneys and hearths for dwelling houses. After the mid-19th century it becomes common for other craftsmen also to be involved in house removals. Rural building, in other words, appears to undergo a gradual process of professionalisation. A time-geographic study shows the time of year when building work was done, and suggests that the households in a hamlet were in a position to do much of the work of relocation themselves. Any external manpower engaged comes from the vicinity, i.e. from within the parish. A surviving day-work ledger compiled during the relocation of a hamlet in about 1880 suggests that relocation assistance was rendered by the neighbouring households and that external labour was used mainly for the skilled operations involved.
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| 7. |
- Liu, Linn, 1985-
(författare)
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A systematic approach for major renovation of residential buildings
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In Sweden, buildings are responsible for about 40 % of total energy use and about 10 % of total CO2 emissions Today more than 60 % of existing Swedish residential buildings are over 40 years old and are in need of major renovation. In addition, 15 % of all multi-family buildings and 27 % of all single-family houses were built before 1945. The increased energy use and threat from CO2 emissions of the building sector create a need for energy efficiency. The important role that renovation of residential buildings will play in reducing the total energy used by the Swedish building sector as well as in reducing primary energy use and CO2 emissions on both the national and global levels has been the impetus for the studies included in this thesis.The aim of the current research is to develop a methodology from a system perspective which can be used to analyze the energy use, optimal life cycle cost (LCC), energy efficiency measure (EEM) package, indoor environment, CO2 emissions, and primary energy use of a building or a community during major renovation. The developed methodology accomplished at three different levels, i.e. building level, cluster level and district level. The methodology considers both energy efficiency and economic viability during building renovation and will also play an important role in overall urban planning. The studied buildings include both non-listed and listed residential buildings and the tools used include building energy simulation (BES), survey, technical measurements, LCC optimization and building categorization.The results show that the combination of BES, technical measurements and surveys provides a holistic approach for evaluation of energy use and indoor environment of the studied residential buildings. The results from the current study also show that the 2020 energy target, i.e., reduction of energy use by 20 %, for the building sector can be achieved by all the studied building types and that the total LCC of these buildings are below the cost-optimal point. In comparison, the 2050 energy target, i.e., reduction of energy use by 50 %, for the building sector may be achieved by the non-listed buildings, but when the constraints relevant to listed buildings are added the cost-optimality changes as some EEMs in direct conflict with the building’s heritage value may not be implemented.The investigation of primary energy use and CO2 emissions by the residential buildings show that the higher the energy saving, the lower the primary energy use becomes, and vice versa. With the same energy saving, the heating system with higher primary energy factor results in higher primary energy use. From a CO2 emissions point of view, EEM packages proposed to help buildings connected to a CHP based district heating system, to reduce the energy use or LCC are not consistently effective. Since these EEM packages will reduce district heating demand, the electricity produced in the CHP plant will also decrease. When the biomass is considered a limited resource, measures such as investment in a biofuel boiler are not favourable from the CO2 emissions point of view. The current study has also shown that combining building categorization method and LCC optimization method will help the community to reduce its energy use, primary energy use and CO2 emissions in a systematic and strategic way.
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| 8. |
- Reindl, Katharina, 1984-
(författare)
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Implementing energy measures in renovations for multi-family dwellings : Influence and practice of professionals
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aging buildings will sooner or later be in need of renovation, which opens opportunities to reduce energy use. Even if economically feasible energy measures or technologies exist, they are not always implemented, leading to an energy efficiency gap. This dissertation deals with how energy measures are handled and why they are enabled or disabled during the planning and design of renovations. During renovations, different kinds of building professionals are engaged, here referred to as middle professionals. The meeting practice of the professionals is investigated, with a focus on how the middle professionals exert influence from the middle-out and to the top and bottom, and how and why they enable or disable measures aimed at energy efficiency or reduction. Three renovation projects are followed in the municipality-owned housing company Stångåstaden, in Linköping, Sweden. The housing company’s goal is to reduce the amount of purchased energy by 25% by 2025. Methods applied during the research are semi-structured interviews, participant observations and document analysis. The conclusions show that energy measures were implemented, but more can be done in renovations. Predefined meeting agendas make the process efficient but not flexible, thus it can be difficult to introduce innovations and alternative ways of thinking into the process. The professionals usually selected measures they had used before. Energy calculations attracted little interest compared to the aggregated knowledge from previous projects, and experience and tacit knowledge were highly valued. This and more lead to a renovation process where it is difficult for energy to enter the current meeting practice.
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| 9. |
- Wallbaum, Holger, 1967
(författare)
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Denk- und Kommunikationsansätze zur Bewertung des Nachhaltigen Bauens und Wohnens anhang der Ökologischen Wohnsiedlung Flintenbreire in Lübeck
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- It is the aim of the present study to detect the reasons for these grievances, taking as an example the new Ecological Housing Estate Flintenbreite, and to demonstrate alternative solutions. For this purpose, different concepts of assessment are employed which meet the requirements of a full life cycle analysis. From the ecological perspective, these are the software tool GaBi of the University of Stuttgart, the MIPS concept of the Wuppertal Institute for Climate, Environment, Energy as well as the software tool GEMIS from the Eco Institute. In order to assess the quantity and quality of the area consumption, a special calculation method was developed on the basis of “Hemerobiestufen”, which illustrate the degree of naturalness of a surface area. The BKI Kostenplaner of the Baukosteninformationszentrum is used to analyze the economic factors. In order to assess social aspects, a special assessment method on the basis of national and international discussions is developed and applied. Apart from taking into account generally accepted ecological indicators, this study also attempts to develop economic indicators as well as indicators for measuring social sustainability of housing development concepts. By means of a working example the practicability of these indicators is examined. For assessing the degree of sustainability reached at the Ecological Housing Estate Flintenbreite 15 indicators are used. These are:•The Total Material Requirement (TMR)•The Accumulated Expenditure of Energy (KEA)•The Global Warming Potential related to 100 years (GWP 100)•Area consumption•Water consumption•Planning and implementation costs•Costs of construction and production•Costs of utilization including maintenance costs•Costs of pulling down, disposal and restoration•Average renting costs•Age composition of the residents•Income structure of the residents•Unemployment rate of the residents•Quota of women employed•Possibilities of participation of the residentsFor assessing and visualizing the several indicators, the COMPASS method, developed at the Wuppertal Institute, is applied.Since the process of construction at the Ecological Housing Estate Flintenbreite has been delayed as a result of the insolvencies of two of the developing companies, up to date only 26 of the planned 119 housing units have been completed. Therefore, in order to obtain valuable results the scientific approach had to be reduced in the course of this study. As the central elements of the approach the building above ground and the sewage concept, which has been used on a larger scale for the first time and which is based on a vacuum technique, are focused on. Apart from savings in water (only 1 liter per flush), this trend-setting, integrated sewage concept takes into account the utilization of nutrients and the energy content of excrements and biological waste. For that purpose, the flows grey water (residues without excrements), black water (toilet residues), rainwater and biological waste are dealt with separately within the whole concept. Through the fermentation of biological waste and excrements, biogas is won which is then used for power production in the housing estate’s own cogeneration plant. Three filters (constructed wetlands in the form of sand filters planted with reeds) are used for clearing the grey water. Using hollows on the 4.9 hectare wide housing development area, rainwater can seep away directly. The liquid manure remaining after anaerobic treatment is collected in a reservoir and used for agricultural means. Thus, nutrient cycles can be completed.Despite partly positive results it must be stated that these building measures, with regard to the building above ground, do not make a valuable contribution as far as more sustainable building is concerned. The sewage concept appears to be more apt to meet this requirement, although optimizing steps have yet to follow.Stakeholders from many different fields can take such steps in their respective discipline but also with regard to the interdisciplinary perspective. The chance to act beyond the boundaries of one’s own discipline, the ability to communicate as a key to joint action as well as the ability to see and open up new paths require new approaches and possibilities of acting. Thus, it is the duty of private persons, functionaries and elected candidates alike to help ensure corresponding education and qualification.Apart from that, on the international level, it is essential to initiate a changed, honest and consistent orientation of the rules of the WTO, the ILO and the UNEP without which a sustainable development will continue to be a utopia. And perhaps we may even have to go one step further and overcome an economy of interest and compound interest that is destroying resources, in order to be able to live the dream of a sustainable economic system.
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| 10. |
- Gontia, Paul, 1984
(författare)
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Material metabolism of residential buildings in Sweden: Material intensity database, stocks and flows, and spatial analysis
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Construction materials are used for the expansion and maintenance of the built environment. In the last century, construction material stock has increased globally 23-fold. Given the current situation, the accumulated stock can be viewed as a repository of anthropogenic resources, which at the end of life could be re-circulated through the economic system to minimize the inflow of raw materials and the outflow of waste. A major step toward increased material circularity is the development of the supporting knowledge infrastructure. For this reason, research has focused on developing methods intended for exposing the material metabolism, namely, estimating the stocks and flows and analyzing the spatial and temporal dynamics of stocks and flows. Residential buildings comprise a large share of the built environment. However, the material metabolism of these structures has remained unknown in many geographical contexts. Therefore, in this thesis, a bottom-up approach is employed to uncover the metabolism of residential buildings in Sweden. This goal is achieved through three methodological steps. First, a material intensity database is assembled based on architectural drawings of 46 residential buildings built within the period 1880–2010 in Sweden. Second, the stocks and flows are modeled with spatial and statistical inventory data and the developed material intensity database. Third, new spatial analysis approaches to the stocks and flows are conducted within urban and national boundaries. For the urban context, material stock indicators defined at the neighborhood level are clustered with well-known algorithms. At the national level, eight settlement types are considered to indicate the spatial dynamics. The developed database indicates historical trends in terms of the material intensity and composition for residential buildings in Sweden. Moreover, the results contribute to establishing a global database and, through an extended international cross-comparison, to the understanding of how the material intensity and composition of residential buildings differ geographically. Furthermore, the stocks and flows are estimated in million metric tons at different administrative boundary levels. Among the six categories considered, mineral-binding materials, such as concrete, comprise the largest share of the accumulated stock. Finally, spatial differences in material stock composition are depicted in urban geography and nationally, among the eight settlement types. At national level, densely built-up corridors are identified, which should be used for enhancing material circularity. This thesis contributes with data source exploration, methodological development, and critical analyses, relevant to researchers, policy makers, and practitioners interested in a more sustained metabolism of construction materials in the built environment.
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