Navigating Towards Circularity Overcoming Barriers to the Use of Circular Aggregates in the Swedish Construction Sector Master’s thesis in Design and Construction Project Management CLARA BERGH VALENTINA JOVIC DEPARTMENT OF ARCHITECTURE AND CIVIL ENGINEERING CHALMERS UNIVERSITY OF TECHNOLOGY Gothenburg, Sweden 2025 www.chalmers.se http://www.chalmers.se/ MASTER’S THESIS ACEX30 Navigating Towards Circularity Overcoming Barriers to the Use of Circular Aggregates in the Swedish Construction Sector Master’s Thesis in the Master’s Programme Design and Construction Project Management CLARA BERGH VALENTINA JOVIC Department of Architecture and Civil Engineering Division of Building Design Dimosthenis Kifokeris CHALMERS UNIVERSITY OF TECHNOLOGY Göteborg, Sweden 2025 I Navigating Towards Circularity Overcoming Barriers to the Use of Circular Aggregates in the Swedish Construction Sector Master’s Thesis in the Master’s Programme Design and Construction Project Management CLARA BERGH VALENTINA JOVIC © CLARA BERGH, VALENTINA JOVIC, 2025 Examensarbete ACEX30 Institutionen för arkitektur och samhällsbyggnadsteknik Chalmers tekniska högskola, 2025 Department of Architecture and Civil Engineering Division of Building Design Chalmers University of Technology SE-412 96 Göteborg Sweden Telephone: + 46 (0)31-772 1000 Cover: Own picture from Swerock’s quarry in Kållered, Gothenbrug 2025. Name of the publisher or Department of Architecture and Civil Engineering Göteborg, Sweden, 2025 I Navigating Towards Circularity Overcoming Barriers to the Use of Circular Aggregates in the Swedish Construction Sector Master’s thesis in the Master’s Programme Design and Construction Project Management CLARA BERGH VALENTINA JOVIC Department of Architecture and Civil Engineering Division of Building Design Chalmers University of Technology ABSTRACT Today the construction sector is a central contributor to global environmental challenges, accounting for a significant portion of resource consumption and greenhouse gas emissions. In Sweden, the urgency for sustainable practices in this industry has become increasingly apparent, particularly as the government pushes for a transition towards a circular economy. This report delves into the complexities of implementing circular material flows within the construction sector, emphasizing the reuse and recycling of aggregates as essential strategies to mitigate environmental impact while enhancing resource efficiency. The primary purpose of this study is to investigate how the Swedish construction industry, with focus on Swerock’s and similar companies' national operations, can strengthen the use of recycled materials and eco-products. By understanding the interplay of legislation, industry practices, and market demand, the study aims to identify practical barriers and opportunities for fostering a circular approach towards material use. Through a comprehensive literature review and an in-depth interview study involving key stakeholders within the construction sector, the research uncovers existing challenges, including insufficient regulatory support, financial barriers, and logistical issues that hinder the integration of reused materials into construction projects. Moreover, it highlights the critical need for collaboration among public authorities, private companies, and other actors to support circular practices. The findings reveal that while the Swedish Environmental Code provides a foundation for sustainable practices, gaps remain in its application that hinders innovative solutions for material reuse. Recommendations for enhancing legislation, encouraging circular practices, and fostering partnerships are provided to facilitate a successful transition into a more resource-efficient construction sector. This research contributes valuable insights not only for Swerock but also for a broader audience in the construction industry, offering a structured approach to promote sustainable material management within the framework of the circular economy. Key words: circular economy, reuse, recycling. II Vägen mot cirkularitet Att övervinna hinder för användning av cirkulära ballastmaterial i den svenska byggsektorn Examensarbete inom masterprogrammet Design and Construction Project management Clara Bergh Valentina Jovic Institutionen för arkitektur och samhällsbyggnadsteknik Avdelningen för Byggnadsdesign Chalmers tekniska högskola SAMMANFATTNING Idag är byggsektorn en central bidragare till globala miljöutmaningar och står för en betydande del av resursförbrukningen och utsläppen av växthusgaser. I Sverige har behovet av hållbara arbetssätt inom denna bransch blivit alltmer påtagligt, särskilt i takt med att regeringen driver på en övergång till en cirkulär ekonomi. Denna rapport belyser komplexiteten i att implementera cirkulära materialflöden inom byggsektorn, med särskilt fokus på återanvändning och återvinning av ballastmaterial som viktiga strategier för att minska miljöpåverkan och öka resurseffektiviteten. Studiens huvudsakliga syfte är att undersöka hur bygg- och anläggningsbranschen, med fokus på Swerocks och liknande företags nationella verksamhet, kan stärka användningen av återvunna material och eco-produkter. Genom att förstå samspelet mellan lagstiftning, branschpraxis och marknadsefterfrågan syftar studien till att identifiera praktiska hinder och möjligheter för att främja ett cirkulärt angreppssätt i materialanvändningen. Med hjälp av en omfattande litteraturstudie och en fördjupad intervjustudie med nyckelaktörer inom byggsektorn, synliggör forskningen befintliga utmaningar. Däribland ingår otillräckligt regelstöd, ekonomiska hinder och logistiska problem som försvårar en smidig integrering av återanvänt material i byggprojekt. Studien lyfter även det stora behovet av samverkan mellan myndigheter, privata företag och andra aktörer för att stärka cirkulära arbetssätt. Resultaten visar att även om miljöbalken utgör en grund för hållbara metoder, kvarstår tillämpningsbrister som hämmar innovativa lösningar för materialåteranvändning. Rapporten presenterar rekommendationer för att förbättra lagstiftningen, skapa incitament för cirkulära arbetssätt samt främja partnerskap, med syftet att underlätta en framgångsrik omställning till en mer resurseffektiv byggsektor. Forskningen bidrar med värdefulla insikter inte bara för Swerock, utan också för en bredare publik inom byggbranschen, genom att erbjuda ett strukturerat angreppssätt för att främja hållbar materialhantering inom ramen för den cirkulära ekonomin. Nyckelord: cirkulär ekonomi, återbruk, återvinning CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 III Contents ABSTRACT I SAMMANFATTNING II CONTENTS III PREFACE ERROR! BOOKMARK NOT DEFINED. ACKNOWLEDGEMENTS VII 1 INTRODUCTION 1 1.1 Background 1 1.1.1 Traditions & Ignorance 2 1.2 Target Group 3 1.3 Aim & Research Questions 3 1.4 Delimitations 4 2 METHOD 5 2.1 Work Process 5 2.2 Literature Review 5 2.3 Interviews 6 2.4 Research Quality 7 2.4.1 Credibility 7 2.4.2 Validity 8 2.4.3 Reliability 8 2.5 Ethics 8 2.5.1 Data Collection 8 2.5.2 Use of Data 9 2.5.3 Use of AI 9 2.6 Limitations 9 3 LITERATURE REVIEW 10 3.1 What is Sustainability? 10 3.1.1 Triple Bottom Line 11 3.2 Steering Laws regarding Reuse in Construction 11 3.2.1 The Swedish Environmental Code 11 3.2.2 The Swedish Waste Regulation (2020:614) 12 3.2.3 Chemical Legislation 12 3.2.4 Circular Economy Act 13 3.2.5 Corporate Sustainability Due Diligence Directive (CSDDD) 13 3.3 Circular Economy 14 3.3.1 Circular Construction 15 3.3.2 ESG 15 CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 IV 3.4 Waste Hierarchy 16 3.4.1 Prevention 17 3.4.2 Reuse 17 3.4.3 Recycling 17 3.4.4 Recovery 18 3.4.5 Landfilling 18 3.4.6 Challenges Connected to the Waste Hierarchy 18 3.5 Life Cycle Assessment 18 3.5.1 Cradle-to-cradle 18 3.5.2 End-of-waste Criteria 19 3.6 Reuse in the Construction Sector 19 3.6.1 Implementation of Reused Materials 20 3.7 Challenges with Reuse 20 3.7.1 Supply 20 3.7.2 Logistics 21 3.7.3 Quality 21 3.7.4 Financial Obstacles 22 3.7.5 Measurability of Reuse 22 3.7.6 Laws & Regulations 23 3.7.7 Innovation Opportunities 23 3.8 Different Stakeholders’ Actions & Responsibilities for Reuse 24 3.8.1 Supplier 24 3.8.2 The Municipality as Client 24 3.9 Potential Solutions to Implementing Circular Economy in the Construction Industry 25 4 EMPIRICAL STUDY 27 4.1 Swerock 27 4.1.1 Eco-concrete 27 4.1.2 Eco-aggregates 28 4.2 Results from the Empirical Study 28 4.2.1 Today’s Regulations & Laws Regarding Reuse & Waste 28 4.2.2 Obstacles with Implementing Reused & Recycled Crushed Aggregates 30 4.2.3 Strategies to Increase the Implementation of Reused & recycled Crushed Aggregates 33 4.2.4 Future Predictions 35 5 ANALYSIS 39 5.1 The Understanding of Reuse & Recycling 39 5.2 Collaboration Among Stakeholders 40 5.3 Challenges in Implementation 41 5.4 Steering Legislation & Municipal Support 42 5.5 Future Predictions & Implementation 43 CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 V 5.6 Summary & Illustration of the Analysis 44 6 DISCUSSION 46 6.1 The Impact of Collaboration in the Swedish Construction Industry 46 6.2 Regulatory Changes to Facilitate the Circular Transition 47 6.3 The Combination of the Three Sustainability Dimensions 49 6.4 Future Potential Actions to Increase Circular Material Flows 49 6.5 Action Plan for Swerock & Stakeholders in the Industry 50 7 CONCLUSION & FUTURE RECOMMENDATIONS 52 7.1 Summary of the Study 52 7.2 Concluding Remarks 53 7.3 Future Research 54 REFERENCES 55 CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 VI Göteborg June 2025 CLARA BERGH VALENTINA JOVIC CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 VII Acknowledgements This study, which covers 30 ECT, was conducted during the spring semester of 2025 by Clara Bergh and Valentina Jovic as an examining part of the Master Program Design and Construction Project Management, civil engineering, at Chalmers university of technology. The aim of our project was to gain a deeper understanding of sustainability processes within the construction sector and how more sustainable materials can be implemented in practice. Sustainability has long been a subject of great interest to us, from environmental, social, and economic perspectives. Working in collaboration with Swerock provided us with valuable insights into current material flows and how they can be improved to support a greener future. Throughout the project, we also came to understand the complexity and challenges facing the industry, and that driving change in sustainability is often a long-term effort even when both the motivation and knowledge are present. This project clearly demonstrated that collaboration is one key to progress, and it has significantly strengthened our knowledge and competence in the field of sustainability. We would like to express our heartfelt gratitude to everyone who contributed to the success of this study. First and foremost, we extend our sincere appreciation to the interviewees who generously shared their time, insights and expertise with us. Their willingness to engage in a meaningful discussion regarding the complexities of reuse and circular economy in the construction sector provided invaluable perspectives that significantly enriched our research. A special thank you goes to our supervisor Dimosthenis Kifokeris, for his strong support and guidance throughout the research process. His expertise and constructive feedback were important in shaping this report and ensuring its academic view. Dimos motivation helped us navigate challenges and refine our approach, and for that, we are truly grateful. We would also like to acknowledge our supervisors at Swerock, Ted Lundberg, Marcus Ljungholm and Frej Hegg, and thank you for making this report meaningful for us and involved actors. With your guidance and encouragement this work has been a joyful experience. As a leading player in the construction sector, Swerock’s commitment to sustainability and innovation inspired us to explore the potential of circular materials in the industry. Lastly, we would like to address our colleagues and peers who contributed their thoughts and encouragement during this journey. Their support made this process not only fruitful but also enjoyable. Thank you all for your invaluable contributions! Gothenburg June 5th 2025 Clara Bergh Valentina Jovic CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 VIII Central Concepts To facilitate the readers understanding a list of key terms is presented below, describing how they are used throughout the report. Circular economy An economic model focused on reducing waste and promoting reuse, recycling and sustainable resource management. Circular materials Materials that are reused, recycled or recovered to extend their lifecycle and reduce the need for raw resources. This includes materials such as excavated masses, recycled aggregates, reclaimed concrete, and other components that are reintegrated into new projects. Procurement Describes the competitive process where contractors bid to secure a contract with a client Quarries Sites where raw materials and aggregates are extracted. Regulatory authorities Agencies responsible for enforcing regulations related to waste management, reuse, recycling and environmental protection. Recycling The process of converting waste materials into new products, reducing the need for raw resources and minimizing landfill use. Reuse The practice of using materials or products again for the same or a new purpose, helping to extend product life cycle and reduce waste. Stakeholder A person, group or organization with an interest or involvement in a decision-making process, project or outcome. Raw materials Natural resources that have not been previously used or processed. CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 IX List of Figures 1.1 Projected future composition of raw materials for aggregate production. (Fossilfritt Sverige, 2024). 3.1 Circular Economy Model (European Parliament, 2023). 3.2 Waste hierarchy (Göteborgs Stad, n.d-b). 6.1 Mind Map of central concepts. Own figure. CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 X List of Tables 1.1 Environmental footprint of the construction sector in 2022. Own figure. Source (Boverket 2025-a). 2.1 This table lists the interviewees along with their roles and companies. 7.1 Overview of a staged action plan outlining key legislative, economic, collaborative and technical measures to drive circular economy practices in the Swedish construction sector. CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 1 1 Introduction The introductory chapter provides a comprehensive overview of the study’s background and the context in which the research has been conducted. It outlines the underlying factors that motivate the investigation, as well as the academic framework to which the study relates. Furthermore, the purpose of the study and the specific research questions guiding the analysis are clearly presented. The chapter concludes with a description of the target groups that are particularly relevant to the study. 1.1 Background The construction and real estate sector play a crucial role in society’s environmental impact, accounting for a significant share of resource consumption and emissions. Statistics from Boverket (2025-a), based on data from Statistikmyndigheten (SCB), indicate that in 2022 the sector contributed between 4% and 39% of Sweden’s total environmental impact, depending on the specific environmental factors being measured, see Figure 1. This makes the construction and real estate sector one of the most resource-intensive industries, with substantial potential to influence national environment and climate policies (Shahid et al., 2024). Furthermore, the shift towards a circular economy in the construction industry is currently in an exploratory phase, where circular construction is secondary and a linear way of working is still the norm (Boverket, 2025-a). An analysis of the sector’s environmental footprint, considering both domestic construction activities and imported building materials, reveals two separate trends over the period 2008-2022 (Boverket, 2025-a). Greenhouse gas emissions and nitrogen oxide emissions have decreased due to improved energy efficiency, advancements in construction techniques and stricter environmental regulations (Ministry of the Environment, 2020). However, other environmental concerns have increased significantly, including higher overall energy consumption and a rising volume of generated waste (Boverket, 2025-a). Table 1: Environmental footprint of the construction sector in 2022. Own figure. Source (Boverket 2025-a). CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 2 While the amount of waste in Sweden is increasing, there is also a distinctly high share in raw material extraction (Sveriges geologiska undersökning, 2023). According to Fossilfritt Sverige (2024), the average Swede consumes 8-10 tonnes of aggregates each year. Of this amount, 90% is extracted directly from rock and moraine, while natural gravel accounts for the remaining 10%. Sweden has set a target to ensure its supply of rock materials is free from fossil fuels by 2045, aligning with the European Union’s climate objectives and addressing the industry’s greenhouse gas emission challenges (Naturvårdsverket, 2024-a). To reach these goals, Fossilfritt Sverige (2024) emphasizes the need for a holistic approach that takes multiple factors into account. Among these, the extraction of raw materials should be reduced, with a stronger focus on preserving natural resources, biodiversity and ecosystem services. The exploitation of raw materials has reached a critical point, necessitating that the industry take action and adopt new approaches, as our previous methods of operation are unsustainable (IISD, 2021). Over the past 30 years, the number of quarries in Sweden has been more than halved, decreasing from 3,440 to 1,117 due to regulations governing material extraction (Fossilfritt Sverige, 2024). The remaining quarries currently produce approximately 90.000 tonnes per quarry. As the number of quarries declines, the need for transportation and environmental impact will increase, as extraction sites become less locally distributed. Figure 1 illustrates the distribution of various materials, showing a downward trend in the use of natural gravel. At the same time, the demand for circular materials is expected to increase significantly over time. Figure 1: Projected future composition of raw materials for aggregate production. (Fossilfritt Sverige, 2024). 1.1.1 Traditions & Ignorance According to Balador et al. (2020), raw materials are often viewed as better and are generally preferred, due to concerns regarding whether recycled materials can perform at the same level as raw materials. While the concept of reuse is well known, many stakeholders still prefer new materials, believing that recycled alternatives may not meet the same standards of quality and functionality. Factors such as a lack of CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 3 trust in secondary materials and the absence of standardized guidelines for their use therefore also influence material selection decisions (European Environmental Agency, 2020). Historically, the construction sector has been strongly reliant on raw materials, making it challenging to shift the focus toward reuse and circular alternatives (European Environmental Agency, 2020). Many stakeholders are hesitant to invest time and resources in developing alternative solutions involving recycled materials, as these often require significant changes in work processes and project management strategies. Attitudes toward change and deficiencies in collective collaboration are also key obstacles to overcome (Boverket, 2024-b). Often, professionals in the sector are reluctant to work when changes in methods and material choices require substantial adjustments (European Environmental Agency, 2020). As a result, the potential benefits of a circular economy, such as increased resource efficiency and reduced waste generation, are not fully realized. 1.2 Target Group This report is intended for stakeholders within the construction sector who are seeking more effective methods for integrating recycled crushed aggregates into their operations. The target group includes both private and public actors, such as municipal authorities and other relevant stakeholders, who have the potential to influence the development of a more sustainable and circular market. By examining the relationship between legislation, industry practices, and market dynamics, the report provides insights that may support both public and private stakeholders in navigating existing regulations and identifying opportunities for improvement. The findings aim to guide efforts toward a more resource-efficient construction sector by highlighting how legal frameworks and municipal strategies can be adapted to promote circular material use. A major company which can take advantage of this report is Swerock, a key player in the construction and civil engineering industry. Given their active involvement in the construction sector, the findings are particularly relevant to Swerock’s ongoing efforts to expand the use of recycled materials within their operations. Swerock has also been a guiding hand and mentor during this work and has provided the report with valuable insights. Therefore, they as a company are also a target group, since the report seeks to understand their operations as well as finding solutions to implement a greater use of recycled crushed aggregates. Given the growing regulatory demands and sustainability goals within the industry, this study seeks to provide insights that support Swerock and similar companies in systematically increasing their use of recycled crushed aggregates. 1.3 Aim & Research Questions The purpose of this study is to examine how the construction and civil engineering industry, with a focus on Swerock’s operations, can promote increased use of recycled crushed aggregates. Furthermore, it will analyze how legislation and municipal guidelines can be adapted to support a more sustainable and resource-efficient development within the industry. The study will therefore analyze how legislation and municipal guidelines can be adapted and changed to support a more sustainable and resource-efficient development within the industry. Lastly, the report aims to look CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 4 into the barriers that hinder today’s development in the area regarding recycling crushed aggregates. The following two research questions will be examined in detail to explore their implications and significance: • What are the main practical and organizational barriers to implementing circular aggregates in the construction process, and in what way could this be improved? • How does the current Swedish environmental legislation affect the possibilities for increased reuse of aggregates in the construction sector, and what changes are needed to facilitate a circular transition? 1.4 Delimitations The delimitations that the study will take into account are to only take the approach from Swerock as a supplier’s perspective and the Municipality of Gothenburg’s role as a client. The study will also only look into regulations in Sweden and how the government and the different municipalities in Sweden decide for the development in Gothenburg city. Information gathered from documents and data should also not be older than 10 years back in time since it’s been a development in reuse the last decade. Another delimitation for the study is that the report will take a general approach and will not examine specific projects where the implementation of reused aggregates may or may not be applicable. CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 5 2 Method This chapter presents the methodology of the study and explains certain strategic choices. Furthermore, it outlines the overall work process, including how relevant literature was identified and selected for review. The chapter also explains the approach taken for conducting interviews and the criteria used for selecting participants. Key aspects of research quality are discussed, with a particular focus on credibility, reliability, and validity. Finally, the chapter addresses the ethical considerations involved in the study, including issues related to the use of AI, data collection, as well as the limitations that affect the study’s scope. 2.1 Work Process The study will take an inductive approach, which aims to create a study based on observations of empirical reality, where general conclusions are derived from specific cases (Collis & Hussey, 2014). Furthermore, this study will be conducted through a qualitative method that aims to gather theoretical data and focuses on understanding concepts, experiences, and processes that cannot be quantified or tested through controlled experiments (Laksham et al., 2000). 2.2 Literature Review A systematic literature review has been used in this study as it aims to compile information within a defined area and since it aims to choose relevant articles specifically (Karolinska Institutet, 2024). We have critically reviewed and carefully selected them to ensure their alignment with the topic, which we ultimately discuss at the end of the study. To ensure the credibility and accuracy of the literature study, primary sources have been used as extensively as possible. Relying on first-hand sources allows for a more direct interpretation of original data, theories and findings, minimizing the risk of misrepresentation. However, in cases where secondary sources have been used, their content has been carefully reviewed and compared with other reliable sources to verify accuracy and consistency. This approach strengthens the reliability of the research by ensuring that the information is derived from its original context and that any secondary interpretations are well-grounded and trustworthy. SO-rummet (2025) points to sources with recent writing and regulatory updates that hold greater credibility, as they provide more up-to-date information. The further removed a source is in time, the more validated it becomes. Based on this, the study has chosen to focus on sources that span a maximum of 10 years to ensure they remain relevant and nuanced and to ensure a trustworthy report, since this subject is in the process of change all the time. The oldest and only exception is Brundtland (1987), as it serves as the foundational reference for sustainability and its definition. Sources lacking a publication year have generally been excluded, with the exception of company websites, such as Swerock’s, where the study assumes the information remains relevant. Furthermore, literature from both Swedish and international publications has been used to receive a nuanced perspective but also to include multiple ways of thinking and reasoning regarding sustainability and reuse. Since the study aims to investigate the Swedish extraction of crushed and ECO-products, regulations and legislation are based on a national level. CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 6 The sources used in this study primarily consist of academic articles and research obtained through Chalmers library, which provided access to reputable databases such as ResearchGate and ScienceDirect. Additionally, information has been gathered from books and academic search monitors, including Google Scholar and Scopus, to ensure a comprehensive literature review. Furthermore, internal reports from Swerock have been analyzed to provide industry-specific insights and practical perspectives, complementing the academic sources and ensuring a stronger foundation for the study. Lastly, information regarding legislation and guidelines was gathered from governmental authorities, such as the European Union and other relevant regulatory bodies. Specific keywords were used to ensure the study included relevant information and made the search process more refined. These keywords included reuse, circular economy, construction sector regulations, sustainability and waste. The keywords were then combined to identify additional relevant articles and provide broader insights for the study. The search was conducted multiple times to ensure the most relevant and up-to-date information was gathered, as new content is constantly emerging. 2.3 Interviews 10 different interviews were conducted, either on site or via Teams, with suppliers and stakeholders within the Swedish construction industry to receive their insight. The duration of each interview was around 1 hour. Different actors besides Swerock were interviewed to gain knowledge from various perspectives. Representatives from Vinnova, Riksdagen, Delphi and Göteborgs Stad were all interviewed. Vinnova, Sweden’s Innovation Agency, was selected to understand the development of circular economy practices in construction from a futuristic point of view. Secondly, Riksdagen, which establishes the legislative framework and regulations in Sweden were interviewed. Their perspectives were crucial in comprehending the creation of laws and regulations. A department specializing in waste and resource management at Delphi, a Swedish law firm, was also a part of the interview study. Lastly, Göteborgs Stad also played a crucial role in understanding the subject of circularity and laws and understanding how they think as a client. In Table 2, all interviewees along with their roles and companies are presented. In chapter 5. Results the interviewees are referred to as respondent 1 to 10 for ethical considerations and to maintain anonymity. See Appendix A for insights into the asked interview questions. The interviews were held with a semi-structured approach to allow space for questions which came up during the interviews but also to follow a common subject and not fall out of line. The semi-structure also made it possible to send the questions to the interviewees beforehand, since they were predetermined, and then follow up questions came up as the interviews went on (Academic Work, 2025). This structure made it possible to adapt the questions regarding who was interviewed. Furthermore, the interview study was based on a thematic analysis to identify repeated patterns and key themes within the interview material (Klang, 2024). The process began with systematically coding the transcribed interviews, where relevant statements were highlighted to capture essential insights. These coded segments were then categorized based on their content, allowing for the identification of overarching CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 7 themes. Through a successive process of comparing and refining these categories, a deeper understanding of the key challenges and opportunities related to the implementation of reused crushed aggregates emerged. This structured approach ensured that the analysis remained grounded in the data while allowing flexibility to incorporate new perspectives that became apparent during the process. Table 2: This table lists the interviewees along with their roles and companies. 2.4 Research Quality Ensuring the quality of a study is a crucial aspect of research. Therefore, three key criteria have been used to evaluate the report’s research quality, which are credibility, reliability and validity. Andersson et al. (2024) define reliability as the ability of a measurement method to produce consistent results when applied repeatedly under the same conditions. On the other hand, Andersson et al. (2024) describe validity as the accuracy with which a method captures its intended measure. High validity indicates that the results accurately represent real-life conditions, whether in a physical environment or a social setting Ensuring both reliability and validity is essential for assembling the last criteria, credibility, where focus is to produce a credible and trustworthy report through research findings (Andersson et al., 2024). Reliability can be further divided into several types, such as internal reliability, which assesses the consistency of results within a study (Middleton, 2025). Another described part is the external reliability, which examines whether the study can be replicated with similar outcomes in different settings. Similarly, validity can be categorized into internal validity, which focuses on the accuracy of the relationship between variables within the study. External validity determines whether the findings can be generalized beyond the specific research context. 2.4.1 Credibility The interviewees selected for the study were considered credible, as they are all engaged in circular practices and sustainability in some capacity. Several of them also possess in-depth knowledge of laws and regulations, providing a deeper understanding of how these legal frameworks influence the transition toward increased circularity in the construction sector. To enhance the study´s credibility, the interviews were recorded and transcribed to ensure the highest possible accuracy in the presented material. A total of ten interviewees were selected as a minimum of CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 8 participants to ensure a diverse range of responses, as the answers reflect individual perceptions and opinions, creating personal bias. 2.4.2 Validity To ensure the validity of this report, the interviews were conducted to also detect current challenges within the field. Regarding potential sources of error, one limitation concerns the number of interviews. Including additional participants would have introduced a wider range of perspectives on the topic and contributed to a more nuanced view of opinions regarding the implementation of circularity. Furthermore, a greater number of interviewees would have strengthened the study’s validity by incorporating more voices, thereby offering a clearer and more representative picture of the current situation. Another perspective of this, could have been to find more specialists from the client’s side. The answers from the municipality were general and therefore this could have been an error, since the answers were not always aligned within the specific area of circular aggregates. 2.4.3 Reliability The questions asked during the interviews have been thoughtfully written to make the interviewees answer freely, without being affected by biases. What questions suit the report the most and contribute to answering the research questions has been reflected on when writing them. Therefore, nothing has been selected in a way to hide relevant information for the readers. Similarly, the sources included in the literature review were selected based on the same principles of transparency and relevance. Efforts were made to ensure that the literature was as up to date as possible, and no perspectives were deliberately excluded. Moreover, if this study were to be replicated under the same conditions and without the emergence of new research, the results would be expected to remain consistent. 2.5 Ethics This study has been conducted with careful consideration of ethical principles to ensure transparency, integrity and respect for the individuals involved. 2.5.1 Data Collection To maintain ethical standards in data collection, all interviews have been recorded with the informed consent of the participants. Prior to the interviews each participant was provided with the interview questions and informed about the purpose of the study ensuring that they had sufficient time to prepare and understand their role in the research. Furthermore, the study has been conducted with an objective approach, ensuring that neither the selection of sources nor the interpretation of results has been influenced by bias. Efforts have been made to include diverse and credible sources, critically evaluating them to provide a balanced and reliable foundation for the research. CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 9 2.5.2 Use of Data To uphold ethical integrity, all interviewees were given the opportunity to review, read and provide feedback on their responses before the study’s publication. Their consent was obtained at multiple stages, both before and after the interviews, ensuring that they were comfortable with the way their input was presented. They were also informed that they did not have to answer questions they were uncomfortable answering. Additionally, to protect the privacy of the participants, all individuals are presented anonymously in the text. This measure was taken to ensure that no personal or identifiable information is disclosed while maintaining transparency in the study’s methodology. 2.5.3 Use of AI AI, in the form of ChatGPT version 4.0, has been used primarily to translate words and sentences from Swedish to English, as well as to check grammatical structure. It has also been utilized to find synonyms for selected words to create a more formal tone in the report. AI has not been used to generate text or answer topic-specific questions, as its reliability cannot be ensured. Since the report is fact-based, AI cannot guarantee that responses are derived from a single, consistent source or that the information is up to date. Additionally, ChatGPT generates different responses depending on how questions are formulated, which is another reason why the reliability of its generated answers cannot be ensured. 2.6 Limitations Several limitations of the study have been considered when writing the report with time being the most significant. The research was conducted within a limited time frame of 6 months, which inevitably have affected the scope of the investigation. This could also have influenced the findings, as certain potential important perspectives and angles could not be explored. The limited period also impacted the data collection process, particularly the ability to identify and conduct interviews with a broader range of relevant stakeholders. Given more time, more interviews could likely have been included, enabling a more comprehensive understanding of the field with more insights. With more time, efforts could have been made to ensure a greater diversity of voices thereby improving the reliability of the conclusion. Since the report is based on exploring the Swedish regulatory frameworks other countries’ solutions have been excluded. By not incorporating international perspectives or comparative approaches the research may have missed potentially valuable insights or alternative methods. International best practices or innovative solutions implemented elsewhere could offer inspiration or serve as benchmarks for the circular development in the Swedish construction industry. However, due to its national focus the study does not explore whether international approaches could be effectively integrated into the Swedish regulatory context. This limits the study’s ability to evaluate potential strategies used abroad, which could have added a wider dimension to the analysis and strengthened the recommendations. CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 10 3 Literature Review Chapter 3 provides a comprehensive overview of current research in the field, divided into several main sections that collectively highlight key aspects of the subject. The chapter begins by introducing the concept of sustainability, followed by an overview of the legislative frameworks that govern reuse in the construction industry, thereby enhancing the understanding of the regulations that influence current practices. Next, the importance of the circular economy and the principles underlying this model are discussed. The chapter also addresses the waste hierarchy and its various levels, highlighting sustainable methods for managing waste. A crucial part of the chapter is dedicated to explaining what reuse entails in practice, as well as identifying the main challenges associated with its implementation. Furthermore, the chapter analyzes the actions and responsibilities of various stakeholders in promoting reuse. Finally, a range of potential solutions is presented to contribute to addressing these challenges and promote a more resource-efficient and sustainable construction sector. 3.1 What is Sustainability? A widely recognized definition for sustainability stems from the report Our Common Future, published in 1987 by the World Commission on Environment and Development. This report, also known as the Brundtland Report, defines sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” (World Commission on Environment and Development, 1987, p. 54). This definition of sustainability emphasizes the two key principles: needs and limitations (Kreye, 2023). The concept of needs focuses on securing a minimum standard of living, particularly for the most vulnerable populations, while limitations refer to the constraints imposed by current technology, social structures and the Earth’s biocapacity. The report also highlights the importance of fairness between generations, making sure that future generations can live on a planet that supports a good quality of life (Brundtland, 1987). Expanding this framework globally, sustainability can be understood as creating the condition in which all people, now and in the future, have access to the resources and environment necessary for survival and prosperity. These ideas have formed the basis for today’s discussions about sustainability and show how environmental, social and economic aspects are closely connected. Agenda 2030 is a vision that includes the UN’s 17 sustainable development goals, aiming to create a better world by 2030 (FN-förbundet, n.d). These 17 main goals are further divided into 169 measurable targets, making it easier to study and track progress. Many of these targets address the three dimensions of sustainability, economic, social and environmental, to create an inclusive and comprehensive vision. Agenda 2030 applies to all countries and societies worldwide, regardless of their level of development, ensuring that everyone is equally committed to achieving a sustainable future. According to Boverket (2024-c), the Swedish construction sector must adapt its industry based on some of the 17 sustainable development goals to promote circularity and the creation of a sustainable future. These include goal 8: decent work and economic growth, goal 9: industry, innovation and infrastructure, goal 11: sustainable cities and communities, goal 12: responsible consumption and CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 11 production, goal 13: climate action and goal 15: life on land. Based on these six goals, Sweden has established a generational goal, aiming to create a society where major environmental issues are resolved before the next generation takes over. 3.1.1 Triple Bottom Line According to Kreye (2023), sustainability encompasses a broader perspective, which includes not only environmental issues but also social and economic dimensions. This broader approach is summarized in the theory known as the triple bottom line (TBL), a framework that evaluates sustainability through three key components: profit, planet and people (3Ps). The idea behind the TBL framework, introduced by John Elkington in 1994 as noted in Kreye 2023, was to encourage companies to consider three separate bottom lines in their operations rather than focusing solely on financial profits. These bottom lines represent the financial, social and environmental performance of a company over time. By incorporating all three dimensions, TBL aims to provide a more comprehensive understanding of the true costs and impacts of doing business. 3.2 Steering Laws Regarding Reuse in Construction The construction sector must comply with numerous sustainability regulations to safeguard the world’s resources and living standards, and this includes applying a life cycle perspective and reporting a building’s climate impact (Boverket, 2020). Targets have been established for waste management to enhance ecological sustainability and improve efficiency (Boverket, 2025-b). 3.2.1 The Swedish Environmental Code The Swedish Environmental Code (Miöjöbalken), which was enacted in 1999, serves as a legal framework designed to support sustainable development and guarantee that future generations can enjoy a healthy environment (Riksdagen, 1998). The aim with the Swedish Environmental Code is also to emphasize individual and collective responsibility for protecting nature (Göteborgs Stad, n.d-a). The Swedish Environmental Code is a consolidation of 16 environmental laws that were used in Sweden during the 20th century, with the first enacted in 1964 and the last in 1994 (Riksdagen, 1998). To enable a broader application this was developed to cover all types of measures, including those related to individuals’ daily lives and commercial activities. The Swedish Environmental Code highlights five key areas, one of which emphasizes the importance of reusing and recycling materials, raw materials and energy (Riksdagen, 1998). The goal is to create a long-term sustainable cycle where resources are used efficiently and environmental impact is minimized. Chapter 15 of the Swedish Environmental Code addresses waste management and the regulations governing how different actors should handle, transport and process waste. These provisions are, according to Riksdagen (1998) crucial to ensure that waste is managed in a way that reduces negative environmental effects and promotes a circular economy, where resources are reused and recycled instead of being wasted. Additionally, Chapter 15 in the Swedish Environmental Code outlines how waste should be managed. Waste management includes physical handling such as collection, CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 12 transportation, sorting, recycling or disposal. Measures should also be taken to facilitate these processes, even without direct physical interaction, for instance, by organizing transportation or transfer of ownership. 3.2.2 The Swedish Waste Regulation (2020:614) The Swedish Waste Regulation (avfallsförordningen) was made to complement the Swedish Environmental Code and contributes with a broader understanding for waste (Riksdagen, 2020). According to Göteborgs Stad (n.d-a), the Swedish Waste Regulation builds upon the Swedish Environmental Code of 1998 by specifying and clarifying regulations for waste management in Sweden. While the Swedish Environmental Code establishes overarching principles such as the waste hierarchy and the distribution of responsibilities, the Swedish Waste Regulation provides detailed provisions regarding waste management and the classification of hazardous waste. Because of the Swedish Waste Regulation, waste can be categorized as either hazardous or non-hazardous, which Riksdagen (2020) further determines how it should be handled and treated. Hazardous waste (FA) contains substances that pose a significant risk to human health and the environment, requiring more strict handling, disposal and recycling measures. Non-hazardous waste (IFA), on the other hand, poses minimal risks and can be managed with less restrictive regulations to ensure environmental safety. According to Naturvårdsverket (2009), a model has been developed to establish guideline values for contaminated soil. The model is based on two main land use scenarios: sensitive land use (KM-känslig markanvändning), such as residential areas, and less sensitive land use (MKM-mindre känslig markanvändning), such as industrial areas. These categories, while not legally binding, guide the management of waste and contaminated soil and serve as a reference for risk assessment. If contamination levels exceed the general guideline values, it does not actually indicate a risk, but further investigation may be required to determine appropriate actions. 3.2.3 Chemical Legislation Chemical legislation aims to provide more comprehensive control over the risks associated with chemicals, both for human health and the environment (Riksdagen, 2007). The legislation seeks to enhance corporate competitiveness by establishing a common market within the European Union. Under this legislation, companies today bear significant responsibility for reporting their usage and assessment of chemical substances in the market. They are also required to demonstrate that these substances are handled safely and that monitoring is conducted for hazardous substances affecting health and the environment. In 1999, the Swedish Parliament decided to implement 15 environmental quality objectives, with an additional objective introduced in 2005 to promote a healthier and safer environment (Riksdagen, 2007). Among these objectives, A Non-Toxic Environment, aims to eliminate substances and metals that are man-made or extracted by humans and that pose a risk to both human and biodiversity. CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 13 Managing resources in a circular economy is difficult, as different legislations regulate products and waste separately (Naturvårdsverket, 2024-c). While chemical legislation applies to the production and use of materials, waste legislation governs how discarded materials are handled and processed. This distinction is crucial for ensuring both environmental protection and sustainable resource management. Companies must act in accordance with these regulations carefully to comply with legal requirements while promoting efficient use of materials and at the same time minimize waste. 3.2.4 Circular Economy Act The Circular Economy Act is an action plan, published by the European Commission, whose purpose is to facilitate the work on implementing circular products, secondary raw materials and waste (European Commission, 2025). As part of this plan, the Commission aims to set standardized criteria defining when waste is no longer considered waste, making it easier to transform it into valuable secondary raw materials. Additionally, it will simplify and strategically expand producer responsibility while increasing demand through guidelines for public procurement. The Commission also highlights that to further strengthen circularity and enhance recycling capacity, they are also considering new measures to make recycling of critical raw materials within the EU more attractive than exporting them. This aligns with the 25% recycling target set in the Critical Raw Materials Act. Moreover, efforts will be made to reduce landfill dependency by improving separate collection systems and promoting reuse and recycling initiatives. 3.2.5 Corporate Sustainability Due Diligence Directive (CSDDD) In the middle of 2024, the European Union’s new regulation corporate sustainability due diligence directive (CSDDD) regarding corporate sustainability responsibility came into action (European Commission, n.d-a). The purpose of the directive is to strengthen corporate accountability for sustainability by ensuring that companies operate in an ethical and environmentally sustainable manner. Businesses covered by the regulations are now required to actively identify, prevent, and address risks related to negative impacts on both human rights and the environment. According to the European Commission (n.d-b) the new CSDDD law serves as a reinforcement of the Corporate Sustainability Reporting Directive (CSRD). The CSDDD, which instead expects companies to take measures to prevent adverse environmental impact, links CSRD’s reporting obligation to that responsibility. The new law focuses on regulating companies’ actual actions to ensure long-term sustainable and responsible business practices. The legislation reviewed in this chapter presents the current legal framework governing environmental responsibility, waste management and sustainability within the construction sector (Naturvårdsverket, 2024-d). Together, these laws aim to ensure safer handling of materials, promote recycling and reuse, and guide companies toward more responsible practices. However, different laws regulate different stages of a material’s life cycle, such as product use and waste handling, which can affect how reuse is approached in practice. It looks like the laws are not comprehensive enough to inform about problems regarding reuse and recycling. As of today, the laws CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 14 are not theoretically informed enough to address these issues. The following chapter introduces the concept of circular economy, which serves as a broader strategy for supporting more sustainable resource flows and complements the legal framework presented here. 3.3 Circular Economy Circular economy is utilized as a strategy for transitioning toward a more sustainable and resource-efficient future (Naturvårdsverket, 2024-e). It helps guide society in the right direction toward achieving desired environmental and climate goals. The principle of a circular economy is based on using a material or product for as long as possible, including the possibility of breaking it down and transforming it into a new product. Figure 3.1 illustrates the concept of circular economy. In this way, sustainable thinking and actions are promoted in a reality that is currently unsustainable. Within a circular economy, a product gains an extended lifespan, and its utility is carefully evaluated to ensure a sustainable transition (Naturvårdsverket, 2024-e). Figure 3.1: Circular Economy Model (European Parliament, 2023). According to Naturvårdsverket (2024-e), implementing a circular economy is essential for transitioning society toward greater sustainability and resource efficiency. The focus lies on conserving raw materials, energy, water and land, while prioritizing the design of products that can be repaired and upgraded. It aligns with the notion that today’s products become tomorrow’s waste, and by reusing materials, society can significantly reduce waste generation. Further, Naturvårdsverket explains that the concept behind a circular economy is for a material to keep its worth while circulating as long as possible with the same high quality. Naturskyddsföreningen (2021-a) also emphasized that acting sustainably and implementing a circular economy must be incentivized. Policy instruments are needed to encourage CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 15 individuals to adopt innovative approaches where reuse becomes the obvious choice. Additionally, such instruments are required to create favorable pricing conditions, as it is often more expensive today to repair than to purchase new products. 3.3.1 Circular Construction According to Stockholms Stad (2021), circular construction is based on the principles of the circular economy and waste hierarchy. Similar to the circular economy, circular construction aims to optimize the use of existing materials, reduce waste generation, and improve the recycling of resources. Moreover, circular construction plays a crucial role in reducing both economic and environmental costs by promoting resource efficiency and sustainable building practices. Stockholms Stad therefore emphasizes the dire need for new regulations and approaches to make circular construction a reality. The aim of a circular economy is also to implement reused and recycled materials in the building sector, and by 2025, 70% of demolition waste should be reused (Boverket, 2024-e). Buildings should also be evaluated in terms of their lifespan; the goal would be to reduce waste and material loss, ensuring that materials retain their purpose even beyond their original intended use. According to Göteborgs Stad (2019) in the year of 2030, 50% of all used aggregates in Gothenburg should consist of reused or recycled materials. The implementation of circular aggregates must be further expanded to achieve a more sustainable production chain and economic viability (Fossilfritt Sverige, 2024). This approach also includes reducing the use of raw materials to preserve natural resources and biodiversity, thereby protecting nature and the environment. The holistic perspective aims to decrease the extraction of raw materials and instead focus on expanding the production of circular raw materials, as circular aggregates contribute to greater climate benefits and reduce transportation needs. According to Gorgolewski et al. (2008) a circular process should be planned from the outset to ensure a fully closed- loop system with zero waste. To achieve this, they state that it requires thoughtful design, clear structures, effective methods and a well-integrated system that enables the reuse of all materials, giving them a new purpose. The Circular Economy Act, which will be published in 2026 by the European Commission, is a way from the EU to implement a circular economy faster and to create an internal market (European Commission, 2025). According to the Commission, some enhancements to the steering law is to create a freer movement of circular materials and waste simultaneously while increasing the supply of high- quality recycled materials. With this law the Commission hopes to drive the demand for recycled resources by introducing clear requirements in public procurement. From this, the new law will establish common guidelines for when waste is transformed to usable secondary raw materials, making both recycling and reuse easier. 3.3.2 ESG ESG stands for Environmental, Social and Governance and serves as a framework for guiding organizations and companies toward a more sustainable future (RISMA, n.d.). This framework facilitates companies in measuring their climate and environmental impact while aligning with the United Nations global sustainability goals. The three pillars encompass areas such as the management of natural resources, relationships CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 16 between organizations and employees, and corporate governance. As sustainability remains a highly relevant topic, it is essential for companies and organizations to engage with these issues and align with societal developments to ensure long-term business success. Additionally, RISMA highlights that there is an increasing discussion about the possibility of ESG regulations becoming mandatory. Consequently, actively addressing these matters is even more critical for companies aiming to maintain a competitive edge in the future. 3.4 Waste Hierarchy In Europe, the construction industry consumes more natural resources than any other industry and is a major source of waste (Zhang et al., 2021). It is responsible for nearly 50% of all raw material extraction and generates more than one-third of the total waste produced (European Commission, n.d-c). Based on this significant impact, construction and demolition waste has been identified by the EU as a priority area for waste management. To make the construction sector more sustainable, circular economy principles have been incorporated into this topic, aiming to enhance material reuse and recycling (Zhang et al., 2021). According to the Swedish Environmental Code (1998) waste refers to “any substance or object that the holder disposes of or is obligated to dispose of”. Furthermore, it is stated that a substance or object that arises unintentionally in a production process is considered a by-product rather than waste if it: is intended for continued use, can be used directly without additional processing beyond standard industrial procedures, has arisen as a natural part of production and does not violate any laws or pose a risk to the environment or human health. Naturvårdsverket (2022), on the other hand, emphasizes that the material conditions can change over time since they can’t guarantee that a risk will not occur in a later stage. Further on, when it comes to the assessment of whether the material poses a risk to the environment or the human health, the intended use location matters. In accordance with this, the implementation of circular materials is slowed down by regulations on waste and by-products, as their classification varies between different cases (Naturvårdsverket, 2024-b). Another factor that slows down the use of circular materials is, in some cases, that it is quickly classified as waste (Fossilfritt Sverige, 2024). Therefore, legislation needs to be clarified and ensured to prevent such obstacles and to avoid laws themselves becoming a barrier to environmentally sustainable development. According to Naturskyddsföreningen (2021-b) the waste hierarchy is a model used within the EU to guide waste management in the most environmentally friendly way possible. It is part of Swedish environmental legislation and aims to reduce the impact of waste on nature by prioritizing different handling methods. The hierarchy consists of five levels, with the top steps being the most sustainable and the bottom ones being the least desirable, see figure 3.2 for illustration (Göteborgs Stad, n.d-b). CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 17 Figure 3.2: Waste hierarchy (Göteborgs Stad, n.d-b). 3.4.1 Prevention In the waste hierarchy, preventing waste is considered the most sustainable approach (Naturskyddsföreningen, 2021-b). In the construction sector, waste prevention is primarily measured by reducing the total mass of construction and demolition waste, which can be evaluated using indicators such as raw material consumption and waste generation (Zhang et al., (2021). According to Boverket (2025-c) the requirements for waste in Plan- och bygglagen were revised in 2020 to include a broader range of waste categories and to facilitate recycling and reuse efforts. 3.4.2 Reuse One of the key strategies for reducing construction and demolition waste is reuse, which extends the lifespan of materials and reduces the demand for new raw materials (Göteborgs Stad, n.d-b). According to Ericsson et al. (2024) reusing materials is often more expensive than using new ones, mainly due to high costs for transport, storage, refurbishment and assembly, especially in countries with high labor costs. Additionally, Ericsson et al. emphasizes that the taxation on reused materials further reduces their economic viability by increasing costs for businesses and discouraging investment in circular economy initiatives. 3.4.3 Recycling Recycling involves converting waste into new materials or products, reducing the need for raw material extraction and thus saving resources and energy (Naturskyddsföreningen, 2021-b). In the construction sector, recycling often includes processing construction and demolition waste so that it can be used in new building projects (Göteborgs Stad, n.d-b). According to Sveriges Miljömål (2023) the Swedish Waste Regulation outlines various requirements for sorting, applying to both producers and collectors of materials, to minimize incineration and landfill disposal as much as possible. CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 18 3.4.4 Recovery Energy recovery is a step in the waste hierarchy where waste that cannot be reused or recycled is converted into energy through processes such as incineration or biogas production (Naturskyddsföreningen, 2021-b). In Sweden, waste incineration is mainly used for district heating and electricity production, reducing dependence on fossil fuels. However, while energy recovery continues to be a more efficient waste management system, it is still considered less sustainable than waste prevention, reuse and recycling. 3.4.5 Landfilling Disposal is the least desirable option in the waste hierarchy and should be used as a last way out when no other alternatives are possible (Naturskyddsföreningen, 2021-b). Sweden has one of the lowest landfill rates in Europe due to strict regulations and investments in recycling and energy recovery (Avfall Sverige, 2023). However, certain materials, such as hazardous waste and contaminated soil, may still need to be disposed of in landfills to minimize environmental impact. 3.4.6 Challenges Connected to the Waste Hierarchy Criticism of the waste hierarchy, according to Fossilfritt Sverige (2024), revolves around the need for clearer definitions of what should and should not be classified as waste, as there is currently a lack of consistent assessments among regulatory authorities in Sweden. This is intended to promote a greater utilization of waste materials and remove the “waste” label, as it hinders progress within the circular economy. 3.5 Life Cycle Assessment Boverket (2024-f) defines a Life cycle assessment (LCA) as a method used to examine how a product impacts the environment throughout its entire life cycle, from cradle to grave. Meaning from the extraction of raw materials from nature to the point where the product is no longer in use and is managed as waste. By conducting an LCA, it is possible to identify which phase of a product’s life cycle contributes the most to environmental impacts. This information can be used to plan and lay the foundation for building in a more sustainable and efficient way. According to Kreye (2023) an LCA consists of three main steps. First, the goal and scope of the analysis are defined, which means setting the boundaries for the study. The next step is to conduct an inventory, where data on environmental impacts from the different stages of the products life cycle is collected and analyzed. The final step is to assess the environmental impacts, examining how various factors such as energy consumption affects the environment. 3.5.1 Cradle-to-cradle In contrast to the cradle-to-grave approach, cradle-to-cradle ensures that a product’s life cycle continues beyond its initial use (Kreye, 2023). Instead of being disposed of as waste, the product or its materials are recycled or repurposed to create new products or components, fostering a circular and sustainable system. According to CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 19 Mohajan (2022) the cradle-to-cradle strategy is viewed as a comprehensive approach that integrates economic, industrial and social aspects. Its goal is to develop systems that are not only efficient but also completely free of waste. 3.5.2 End-of-waste Criteria According to the European Commission (n.d-d), fostering a strong recycling market requires reducing regulatory barriers for high-quality and waste-derived materials so they can circulate freely like primary raw materials. To achieve this, it is necessary to determine the stage in the recovery process where such materials cease to be classified as waste. This is governed by end-of-waste criteria, which are established through detailed assessments of technical, economic and environmental factors to ensure safety and market viability (European Commission, n.d-d). End-of-waste criteria determine the point at which a material stops being considered waste and is instead recognized as a usable product or secondary raw material (European Commission, n.d-d). Materials can be reclassified from waste to product after undergoing a recovery process, such as recycling, if it meets the following four conditions: • It serves a clear and recognized purpose. • There is an existing market or demand for it. • It meets all necessary legal, technical and regulatory requirements for its intended use. • Its use does not pose risks to human health or the environment. While these criteria aim to streamline the transition from waste to resource, their practical implementation presents challenges (Naturvårdsverket, 2024-d). Sweden’s national waste plan for 2024-2030 highlights several difficulties in aligning with both EU and national environmental targets. The plan underscores that many key stakeholders lack the necessary insight into how they can contribute to more efficient waste management and circular resource use. One of the main obstacles described is the complexity of evaluating when a material should no longer be classified as waste. 3.6 Reuse in the Construction Sector Reuse involves the potential to repurpose a product or material for a new application once its original purpose has been fulfilled (Boverket, 2024-g). The material must not wear out or degrade too quickly but should remain fully functional over a long lifespan, even as a reused material. Reuse also refers to the process of developing a new product or material, with considerations from the outset regarding how the material can be repurposed after serving its primary function. This process, presented by Boverket (2024-g), includes preparations for reuse, regardless of whether a product is reused directly without ever being classified as waste or if it has previously been considered waste but undergone a process to once again be defined as a product. Sweden’s high greenhouse gas emissions, caused by the construction sector, highlights the critical importance of implementing new policy instruments for construction materials (Boverket, 2025-a). The Nordic Council of Ministers established, in September of 2023, a new declaration aimed at strengthening Nordic CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 20 collaboration on low-carbon construction to ensure a greener way of working as well as promoting circular principles within the construction industry. A system based on reused materials creates long-term and sustainable opportunities for materials to serve new purposes (Byggfakta, 2023). Construction and infrastructure projects continuously generate surplus rock materials, which can be reused as filling materials, base layers and reinforcement layers (Fossilfritt Sverige, 2024). By harnessing the recycling potential of these materials, essential raw materials can be utilized more sustainably while also reducing transportation needs. Recycled materials play a crucial role in securing a region’s material supply, making it essential to take full advantage of these resources. To achieve this, Fossilfritt Sverige highlights that better insights and statistics on the availability and use of excavated rock and soil materials are needed. 3.6.1 Implementation of Reused Materials By sorting and recycling materials such as concrete, wood, and metals, climate impact can be significantly reduced, and resources can be used more efficiently (Boverket, 2024-h). Boverket also emphasizes the importance of identifying barriers to recycling, such as a lack of standardisation and logistical infrastructure, in order to increase recycling rates and foster more sustainable construction. According to Bygg Naturligt (2023), the construction industry generates large amounts of waste, much of which can be recycled or reused, thus reducing the need for new raw materials and minimizing the waste sent to landfills. Additionally, reusing construction materials can be more cost-effective than purchasing new ones. They also highlight the importance of carefully inventorying and quality-checking materials before reuse to ensure safety and sustainability. The extraction of natural aggregates is becoming increasingly restricted due to urban expansion, zoning laws, rising costs and environmental considerations (Wilburn & Goonan, 1998). Recycling converts waste into a usable resource and offers several benefits: 1) it helps conserve natural resources by extending their availability, 2) it minimizes environmental impact near construction sites and 3) it supports the sustainable management of raw materials. Traditional aggregate material can often be recycled with relative ease, either by reusing them as they are or by crushing larger pieces into smaller fractions (Dawson, 2014). 3.7 Challenges with Reuse The concept of reuse isn’t something new to the construction sector, it is rather the implementation process that is often considered challenging (RISE, n.d-a). According to Byggfakta (2023), one of the key challenges of reuse and recycling is achieving industry-wide collaboration and transitioning from a linear to a circular approach. 3.7.1 Supply According to Boverket (2024-g), the availability of reused building material is increasing, and interest in them has also accelerated. However, their use remains limited in scope. This is largely due to the perception that the market for reused building materials is still immature and there is a lack of knowledge regarding how to CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 21 implement reuse effectively. While reused materials are currently being utilized, their adoption remains relatively low compared to raw material extraction. To expand the supply of reused materials, greater market knowledge is required, along with new business models that incentivize the conservation of reused products. Furthermore, Boverket (2024-g) highlights that supply constraints can be addressed through reuse, particularly by repurposing existing structural building components, such as wood, steel and concrete. This could lead to costlier projects and delays, since these components are essential for construction projects. This could, according to Boverket, be mitigated if the necessary materials are already available as reused resources on the market. Reuse can therefore reduce project vulnerability by ensuring that critical components are readily accessible while simultaneously making projects more environmentally sustainable through their implementation. 3.7.2 Logistics One of the main challenges is the difficulty in connecting suppliers with those in need of reused materials, since the reuse market is often seen as fragmented and lacking a well-structured network (RISE, n.d-a). This disconnect can create inefficiencies, making it harder for reclaimed materials to be redistributed effectively and used to their full potential. In the construction industry, a major issue is that surplus material does not always have an immediate use or a clear receiver (Trafikverket, 2022). Without efficient systems for storage and coordination, this therefore becomes problematic when valuable resources risk being rejected rather than repurposed. Currently, it is also often up to the individual projects to identify opportunities for reuse, such as finding other projects or maintenance operations that could benefit from the leftover materials. Additionally, as more quarries shut down their operations, the distance to remaining suppliers and their products increases, further complicating access to raw materials and driving up transportation costs (Fossilfritt Sverige, 2024). Although there is a strong ambition to phase out fossil-fuel-based transportation and transition toward more electrified alternatives, time remains a critical factor in the industry. Transporting materials over long distances is not only costly but also unsustainable in the long run. Therefore, there is a growing emphasis on finding more localized solutions, potentially even on-site processing and reuse, to reduce dependency on long-distance transport and create a more efficient and circular construction process (Naturskyddsföreningen, 2021-c). 3.7.3 Quality A significant challenge in increasing the use of recycled construction and demolition waste materials is the trust in their quality (European Commission, 2018). Industry stakeholders remain hesitant to adopt secondary materials due to concerns about their reliability, consistency and performance compared to raw materials. There is a lack of confidence, which slows down the transition to more sustainable building practices and limits the demand for recycled products. The lack of comprehensive and reliable data on both existing and historical buildings also makes it difficult to determine the exact composition of materials recovery during demolition (European Environmental Agency, 2020). This uncertainty can lead to challenges regarding sorting and processing, ultimately affecting the quality of reclaimed materials. Without accurate CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 22 records, materials may be mixed, damaged, or contaminated, which limits their potential for reuse. In an interview study carried out by the European Commission (2018), it was found that one of the biggest obstacles to the increased use of recycled construction and demolition waste (CDW) is the opinion that these materials are of lower quality. Many stakeholders still view CDW as waste rather than valuable resources, which creates resistance to incorporating them into the design and construction of new elements. However, more recent research indicates that recycled materials can indeed meet the same performance standard as new ones (Chen et al, 2024). In fact, recycled materials used in construction adhere to the same quality standards as raw materials, ensuring that they meet all necessary codes and regulations. A key concern is also the lack of long-term data on the durability and performance of these materials over time (European Commission, 2018). There is a lack of long-term usage data on recycled materials, so their lifespan and function compared to raw materials is uncertain. In contrast to this, Chen et al. (2024) emphasizes that recycled products are regulatory tested to ensure they match or exceed the required criteria for safety, durability and efficiency. 3.7.4 Financial Obstacles Financial barriers to reuse, according to Fastighetsägarna (2024), primarily stem from the immature quality control processes currently in place on the market. Due to the limited availability of reused materials, these controls are not being sufficiently developed, making them both time-consuming and costly. Therefore, investment in research is needed to establish standardized methods for conducting quality assessments, ensuring that each project does not require its own unique and specific evaluation process. Furthermore, Fastighetsägarna emphasizes the need to update procurement and business models to promote the use and profitability of reused building materials, as current models tend to favor raw materials. Both the adoption and market expansion of circular materials are further constrained by current costs, as it remains cheaper to purchase new materials than to buy reused ones (Naturskyddsföreningen, 2021-a). With this in mind, economic benefits must be considered, as reuse aims to reduce purchasing costs, as recycled materials are expected to become cheaper over time than newly extracted ones (Boverket, 2024-a). It also lowers waste management costs for society as a whole. This leads to a desired circular economy where reuse is a key component of such a system, where resources are kept in use for as long as possible. 3.7.5 Measurability of Reuse Sustainability is primarily measured through life cycle assessments, circular economy models, and a product’s carbon emission, with the process for reused materials following the same frameworks (Larsson et al., 2016). According to Boverket (2023), a study was conducted during 2020 to assess the climate impact of new construction. The collected data was intended to serve as reference values for climate impact, providing an indication of how new construction affects Sweden’s emissions and the industry’s overall carbon footprint. Climate declarations are among the key tools used CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 23 to measure sustainability impacts in various building materials and these declarations can potentially be compared to assess the effectiveness of reused materials. However, to enable fair and meaningful comparisons, the framework behind climate declarations must be further developed to account for the specific characteristics and benefits of reused materials (Boverket, 2023). Byggföretagen (2022) also highlights climate budgeting as an additional method for measuring the sustainability impact in different building materials. A climate budget involves calculating a project’s total emissions, assessing its environmental costs and identifying how sustainable decisions can be made. Climate budgeting includes key elements previously mentioned, such as LCA, carbon emissions and the collection of environmental product declarations. While these methods enhance the efficiency of sustainability assessments, they are not specifically tailored to reused materials. Boverket (2024-a) highlights that requirements concerning the reuse or recycling of materials can present challenges within the construction sector. In accordance with this, there is currently no clear method for calculating the proportion of reused materials and their environmental impact. This absence of clear guidance creates uncertainty for both clients and contractors, who may struggle to demonstrate environmental performance in a consistent or comparable manner. Furthermore, Boverket (2024-a) also presents that it is not defined whether all materials should be valued equally in such a calculation. This lack of differentiation complicates both documentation and evaluation in sustainability efforts regarding reuse. 3.7.6 Laws & Regulations Swedish legislation on waste and waste management is based on EU regulations, which guide how member states implement and manage waste. (Naturvårdsverket, n.d.). According to the Swedish Environmental Code, all waste must be handled in a manner that safeguards human health and the environment, ensuring that neither people nor nature are harmed in the process. One of the main barriers to implementing reuse is the legal restrictions surrounding waste and materials, which make it challenging for companies to effectively integrate reuse into practice (Naturvårdsverket, 2024-e). According to Trafikverket (2022) it would also be preferable to further develop the requirements that encourage future reuse and recycling from a more practical perspective. This could include setting specific standards for design and construction methods that facilitate dismantling, sorting and material recovery at a later stage. 3.7.7 Innovation Opportunities By challenging traditional construction norms and embracing a circular economy, along with new legislation, new visions for a greener future can be promoted (RISE, n.d.-b). Previously, legislation in Sweden hindered the implementation of reuse, but progress is being made with new regulations that aim to encourage the choice of reusing materials. The EU is also imposing requirements on eco-design within the construction sector, creating financial incentives for the reuse and recycling of materials wherever possible. Further factors that can drive innovation opportunities include various types of certifications, which can motivate companies to improve and promote reuse. However, according to RISE, the challenge of innovation in reuse lies in the numerous barriers that obstruct forward progress. These include difficulties in CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 24 knowing what materials are available to work with, as they may come from diverse sources. 3.8 Different Stakeholders’ Actions & Responsibilities for Reuse A holistic approach to reuse requires active participation from all actors along the supply chain (Tabas et.al, 2024). Each stakeholder has a distinct yet interconnected role, ensuring that materials and products are efficiently repurposed rather than discarded. A well-functioning reuse system depends on seamless collaboration, where responsibilities are distributed rather than resting solely on one actor. By integrating reuse into the entire supply chain, businesses and municipalities can create more resilient and resource-efficient systems that align with circular economy principles. 3.8.1 Supplier Suppliers can promote sustainable practices and execution in projects by reducing material usage in processes, minimizing energy consumption and ensuring sustainable transportation (Worldfavor, n.d.). Additionally, they need to strengthen their value chains, meaning their connections with organizations and clients, to facilitate sustainable operations both socially and environmentally. To remain competitive and compliant, suppliers must integrate sustainability into their working methods and mindset, failure to do so may lead to challenges with regulatory authorities and customers. It is also crucial for customers to monitor suppliers’ efforts, guiding future sustainability improvements and assessing past performance to optimize their process chains. According to Business Region Göteborg (2021), an early-stage strategy is essential for implementing reuse and sustainability in construction processes, with suppliers playing a key role. A critical factor is that both property owners and construction companies must function as suppliers of materials while also acting as buyers to support circular practices. Business Region Göteborg further emphasizes that industry actors must be capable of both purchasing and selling reused materials, as well as improving the management of existing resources during potential demolitions, where waste may be generated. To implement greater reuse in the process, suppliers and more stakeholders need to increase knowledge about its benefits, including the economic, environmental and waste-related savings it generates. 3.8.2 The Municipality as Client The clients are the project owners and have the main responsibility of the overall planning and implementation to receive the wanted outcome of the project (NFU Mutual, n.d.). They also finance the construction project which does make them the ones with the final say in decisions. Achieving the desired outcome requires a combination of well-thought-out design, effective planning and high-quality construction. According to Albarami et al. (2020) clients must ensure complete satisfaction, to foster a clear understanding of quality requirements throughout the process. CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 25 When the client obtains land and takes responsibility for the construction, they may sometimes be required to meet specific conditions. For example, this includes adopting a sustainable mindset in which clients are required to use sustainable products and minimise waste (SKR, 2023). Such requirements are often part of broader urban planning policies aimed at promoting sustainability or environmental responsibility (Government Offices of Sweden, 2018). By enforcing these conditions municipalities ensure that new developments align with long-term community goals and regulatory frameworks. Certain initiatives driven by the client may also qualify for subsidies from the municipality (United Nations, n.d.). These financial incentives are often provided to encourage sustainable conditions. By offering subsidies, municipalities aim to support projects that align with the urban planning goals and environmental policies, making it more feasible for clients to meet specific requirements while reducing overall costs. Municipalities play a central role in all construction projects, serving both as direct clients and as key regulatory authorities (Boverket, 2024-i). Even when they are not directly responsible for a project, they oversee the permitting process and ensure that developments align with the detailed development plan. Their involvement extends beyond administrative oversights, as they also carry significant responsibility for promoting sustainable construction practices. They can for example promote projects and procurement by setting requirements for materials and working methods (Boverket, 2024-a). It is important to acknowledge that municipal policies and regulations are not established independently but are instead shaped by national objectives and legislative frameworks (Vanhuyse et al. 2023). In Sweden, municipalities are required to align their guidelines with the country’s overall sustainability and development goals. These national directives are further influenced by higher regulatory frameworks at a state level, often guided by European Union policies and international agreements (Government Offices of Sweden, 2021). With this in mind, municipal decisions regarding urban planning, environmental standards and resource management are integrated into a broader system of governance, ensuring adherence to both national and international sustainability objectives. 3.9 Potential Solutions to Implementing Circular Economy in the Construction Industry As of today, both nationally and in the EU, the producer is not responsible for waste management for their own products (Boverket, 2024-a). Through this, the producers have low incentives for driving a change where it is easier to reuse and recycle their materials. This means they do not account for the costs of managing the material once they become waste. A major issue is materials that often end up in landfills, where they cannot be recycled or reused, resulting in high costs for their disposal at waste management facilities. Therefore a solution presented by Boverket is an implementation requiring producers to take responsibility for their products even after they have been used. By offering take-back systems, old products can be collected, recycled and reused instead of becoming waste. This reduces the need to extract new raw materials and encourages better methods that make recycling easier. CHALMERS, Architecture and Civil Engineering, Master’s Thesis ACEX30 26 Today, the negative environmental impacts are not included in the price of using newly extracted materials, which makes it difficult to make recycled or reused materials profitable (Boverket, 2024-a). This means that producers and consumers do not consider the long-term environmental costs when purchasing or using materials. As a result, the use of materials increases, which can lead to greater environmental and climate impacts, especially if the materials are harmful to the environment. To address this, Boverket highlights that it may be necessary to implement measures where those who produce and sell building materials also take responsibility for the costs that arise when the product becomes waste and needs to be recycled. This could involve companies paying for the management and recycling of the materials when they are removed from the site. A solution from Naturvårdsverket (2022) is to look into the definition of waste to facilitate the implementation of reused and recycled materials. Naturvårdsverket emphasizes the importance of a management approach that facilitates the creation of a resource-efficient cycle, which in turn will lead to a broader circular economy. Through a clarification of the waste concept in different scenarios, a consistent assessment can be ensured nationwide, and this will contribute to predictability for the affected operators. Another solution that Naturvårdsverket (2022) is actively working on is an analysis of the criteria that determine whether a material should be classified as waste or not. This involves assessing in which situations a material must be treated as waste. For example, when someone disposes of waste, intends to dispose of waste or is obligated to do so, and when waste can be exempt from waste regulations. Naturvårdsverket is currently developing a comprehensive guidance document, which they hope will provide clearer guidelines on how the definition of waste and other key related concepts should be interpreted and handled. To promote a greater implementation of reused materials, Boverket (2024-a) has proposed that requirements concerning building permits should be incorporated into the Planning and Building Act (PBL) to regulate the use of reused materials in new construction. To ensure a successful implementation, Boverket emphasizes the need for financial policy instruments to encourage sustainable production of circular products and facilitate the transition from linear to circular business models. This proposed transition would incentivize companies to develop more competitive business models while increasing resource efficiency and contributing to reducing environmental and climate impacts. CHALMERS Architecture and Civil Engineering, Master’s Thesis ACEX30 27 4 Empirical Study The following chapter presents the empirical study that forms the foundation for the research question of the thesis, focusing primarily on Swerock as the main stakeholder. The chapter begins with a brief overview of Swerock as a company, including its historical development. This is followed by a more in-depth exploration of the company’s sustainable product offerings, such as eco-concrete and eco- aggregates. Lastly, the results from the conducted interview study will be presented. 4.1 Swerock Swerock was founded in the 1920s and is part of the PEAB Group, one of the largest construction and civil engineering companies in the Nordic region (Swerock, n.d-a). The company is one of Sweden’s largest suppliers of aggregate materials and currently operates approximately 150 quarries across the country. In the Gothenburg area, Swerock operates two quarries, Arendal and Kållered. The Kållered quarry was opened in the 1930s and has grown to become one of the largest in the country, extracting approximately 1 million tons of aggregate materials every year (Swerock, n.d-b). Swerock is therefore one of Sweden’s largest companies in the construction and civil engineering sector, supplying materials such as concrete, aggregates, material recycling, soil remediation and more, with a clear focus on reducing the overall climate footprint of the industry. Swerock places significant emphasis on transitioning and working towards the 2030 climate goals, prioritizing the reduction of the construction sector’s climate-impacting emissions by half (Swerock, n.d-c). They contribute to this by setting their own climate targets and adopting a circular, fossil-free approach to create a greener industry, where every stage of the supply chain becomes more climate-conscious. To achieve these goals, the company focuses on innovation, transparency and measurability, including the implementation of eco-concrete and eco-aggregates, which collectively help to reduce climate impact. Swerock also accepts various types of residual materials, such as concrete, asphalt and other waste materials from different construction projects (Swerock, n.d-d). Through the reception and sorting of materials, their work aims to reduce the amount of waste sent to landfill and instead recycle these materials into new products. The idea is also that consumers who drop off surplus materials should be able to take new materials with them, promoting a circular economy and reducing the number of transport movements. 4.1.1 Eco-concrete Swerock is currently transitioning into a more sustainable operation, with their eco-