Reuse of Construction Materials A study on how a strategic collaboration can facilitate the reuse of construction materials Dana Trabulsi & Milan Sofipour

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DEGREE PROJECT

REAL ESTATE AND CONSTRUCTION MANAGEMENT

REAL ESTATE ECONOMICS AND CONSTRUCTION PROJECT MANAGEMENT

MASTER OF SCIENCE, 30 CREDITS, SECOND LEVEL STOCKHOLM, SWEDEN 2020

Reuse of Construction Materials

A study on how a strategic collaboration can facilitate the reuse

of construction materials

Dana Trabulsi & Milan Sofipour

TECHNOLOGY

DEPARTMENT OF REAL ESTATE AND CONSTRACTION MANAGEMENT

ROYAL INSTITUTE OF TECHNOLOGY

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Master of Science thesis

Title: Reuse of construction materials. A study on how a strategic collaboration can facilitate the reuse of construction materials.

Author(s): Milan Sofipour & Dana Trabulsi

Department: Real Estate and Construction Management Master Thesis number: TRITA-ABE-MBT-20403 Supervisor: Agnieszka Zalejska Jonsson

Keywords: Circular Economy, Construction Material Reuse, Strategic Collaboration, Reverse Logistics

Abstract

The world’s population alongside the general consumption and use of natural resources has grown immensely during the past decade. The construction sector is today one of the industries that has the highest impact on the environment. Therefore, the current linear economy has to be moved towards a circular economy which aims for material- and resource efficiency. The concept of reverse logistics for reuse of construction material and the need for collaboration has been identified as key areas for transitioning to a circular economy and thus has a decisive role in reducing the construction waste. However, due to the construction industry being fragmented, a lack of collaboration amongst real estate developers and other market actors has been identified as a barrier for successfully implementing the reuse of construction materials. Furthermore, the real estate developer is seen as a key actor to utilise the potential of the reuse of construction materials by creating incentives and collaborations with other actors involved.

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Acknowledgement

This master thesis marks the final moment for the five-year Degree Programme in Civil Engineering and Urban Management at KTH Royal Institute of Technology in Stockholm, Sweden. The degree project has been written within the Master’s Programme Real Estate and Construction Management, at the School of Architecture and Built Environment and has been conducted in the spring of 2020 in collaboration with Vasakronan AB.

First and foremost, we would like to sincerely thank our supervisors, Agnieszka Zalejska Jonsson at KTH Royal Institute of Technology and Kubra Ayata at Vasakronan AB, whose important input, guidance, support and commitment made this study possible.

We would also like to thank Vasakronan AB for giving us the opportunity of conducting this study. Furthermore, we would like to thank all the participants in the interview for taking the time to provide us with valuable inputs, reflection and thoughts in this study, despite the ongoing pandemic. Without you, this study would not be possible.

Last, but certainly not least, we would like to sincerely thank all our loved ones for the constant support you have given us during all these years at KTH Royal Institute of Technology. Milan Sofipour & Dana Trabulsi

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Examensarbete

Titel: Återbruk av byggmaterial. En studie på hur ett strategiskt samarbete kan främja å terbruk av byggmaterial

Författare: Milan Sofipour & Dana Trabulsi Institution: Fastigheter och Byggande

Master Thesis number: TRITA-ABE-MBT-20403 Handledare: Agnieszka Zalejska Jonsson

Nyckelord: Cirkulär Ekonomi, Återbruk av Byggmaterial, Strategiskt Samarbete, Omvänd Logistik

Sammanfattning

Världens befolkning har i samband med den generella konsumtionen samt vår användning av naturresurserna ökat avsevärt det senaste decenniet. Bygg- och fastighetssektorn är idag en av de industrier som har störst påverkan på vår miljö. Därav behövs en skiftning från den linjära ekonomin till en cirkulär ekonomi som grundar sig i material- och resurseffektivisering. Konceptet omvänd logistik för ett ökat återbruk av byggmaterial och behovet av samarbete har identifierats som viktiga verktyg för skiftet mot en cirkulär ekonomi och därmed en minimering av byggavfall. Då byggbranschen idag är fragmenterad har bristen på samarbete mellan fastighetsägare och andra aktörer identifierats som en utmaning för att implementera återbruk av byggmaterial med framgång. Vidare ses fastighetsägare som en huvudaktör som kan utnyttja potentialen som finns kring återbruk av byggmaterial genom att skapa incitament och samarbeten med andra involverade aktörer.

Därför var syftet med denna rapport att utreda olika aktörers perspektiv på återbruk av byggmaterial inom bygg- och fastighetssektorn samt vad de främsta barriärer och incitament är för att de ska implementera det. Vidare, genom att få en förståelse för samtliga aktörers perspektiv var målet att skapa en modell för hur fastighetsägarna kan uppnå ett strategiskt samarbete med olika aktörer för att effektivisera processen av återbruk av byggmaterial vid en hyresgästsanpassning.

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Förord

Detta examensarbete markerar det slutliga momentet av det femåriga civilingenjörsprogrammet Samhällsbyggnad vid Kungliga Tekniska Högskolan. Examensarbetet har skrivits inom mastersprogrammet Fastigheter och Byggande på skolan för Arkitektur och Samhällsbyggnad våren 2020 i samarbete med Vasakronan AB.

Först och främst vill vi tacka våra handledare, Agnieszka Zalejska Jonsson på Kungliga Tekniska Högskolan och Kubra Ayata på Vasakronan AB, vars viktiga åsikter, vägledning, stöd och engagemang möjliggjorde denna studie.

Vi vill dessutom tacka Vasakronan AB för att ha gett oss möjligheten att få genomföra denna studie. Vidare vill vi tacka samtliga som deltagit i intervjuerna samt tagit sig tiden att förse oss med viktiga åsikter, reflektioner och tankar i denna studie, trots den rådande pandemin. Utan er skulle denna studie inte vara möjlig.

Sist men absolut inte minst skulle vi vilja tacka våra nära och kära för det konstanta stöd ni har gett oss under alla dessa år på KTH.

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1. Introduction

This chapter aims to present the background to the study, the purpose of the study as well as the research questions this study intends to answer. Furthermore, the limitations of the study are presented in this chapter.

1.1 Background

The world’s population is rapidly growing. In less than a century, the world’s population has grown by over a threefold, to a total of 7,7 billion in 2019 (Roser et al., 2020). Alongside our increase in population, digitalisation and mass production, the general consumption in the world has risen (Dobers & Strannegård, 2005). As the earth’s resources are limited, it is of great importance that the resources are preserved and managed sustainably. Resource efficiency is essential to achieve, as extraction and the production of material has an immense effect on the environment (European Environment Agency, 2016).

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Commission, 2018). However, the percentage rate mainly accounts recycled materials, which distinguishes from reused materials. Recycled materials are existing materials that are turned into raw or processed material which can be used again, normally for another function. While reuse refers to a material product that is used again to fulfil the same function as it was intended for before (European Commission, 2018). In order to achieve the directive framework objective, the European Union issued a waste hierarchy which prioritises the waste management principles in order to prevent harm against humans, environment and wildlife. see figure 1.1. The hierarchy consists of five different management steps; prevention, preparation for reuse,

recycling, recovery and disposal.

Fig. 1.1. EU’s waste hierarchy. Figure inspired by The European Commission's waste hierarchy (2008)

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Fig. 1.2. Illustrations of the material process of linear and circular economy. Source: van der Heijden et al., 2017

There are several research papers investigating the potentials of reuse of construction materials and how to improve the management of construction waste. However, little progress has been made in practice to address the implementation of construction material reuse. There is a consensus among researchers that reuse of building materials in the real estate- and construction sector has a decisive role to play in reducing waste. Previous research has identified the concept of reverse logistics which is a process within reverse supply chain, as an important tool in terms of alleviating environmental issues such as material reuse in the manufacturing and construction industry (Hosseini et al., 2014). However, some of the biggest obstacles in implementing material reuse that need to be addressed are; limited access of secondary materials with sufficient quality, lack of infrastructure necessary and few market actors with low incentives for cooperation (Nußholz et al., 2019). Furthermore, the real estate- and construction sector is fragmented and hierarchical, causing a lack of dialogue between real estate developers, architects, designers, contractors and demolition contractors. Therefore, increasing collaboration and networking may facilitate and expand the knowledge and understanding of life cycle concerns in design and construction. A lack of cooperation of all parties such as real estate developers, contractors, subcontractors, waste contractors, architects and designers are identified amongst others, as a barrier for successfully implementing reuse of construction materials (Nakajima & Russell, 2014).

Raw Materials Production Use Waste Raw Material Production Use Reuse and Recycle

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Previous research in the area of material reuse have mostly been focused on the barriers and the opportunities that arise from implementing it. However, there has been a lack of research on how collaboration amongst different actors can facilitate reuse of construction materials and how such a collaboration can be manifested.

1.2 Problem Formulation

The real estate- and construction sector stands for a high amount of the waste produced in Sweden. Although the European Union has established a waste hierarchy with the goal of having 70% of all construction waste reused or recycled by 2020, only a small amount of all construction waste is currently being reused in Sweden (European Commission, 2018). This indicates an unutilised potential in reusing construction materials and the real estate developer is seen as a key actor to utilise the potential of it by using its influence to create incentives for other actors involved (Miliute-Plepiene et al., 2020; Andersson et al., 2018). The need for a collaboration between different actors in the real estate- and construction sector has been identified as a key driver to further facilitate the material reuse process. However, currently there is a lack of established models which emphasises on the collaboration between a real estate developer and different actors in the material reuse process, which is what this paper aims to provide.

1.3 Purpose

The purpose of this study is to develop an understanding of different actor’s perspectives in the real estate- and construction sector regarding reuse of construction materials and identifying what the key barriers and incentives are for them to implement it. Furthermore, by gaining an understanding of each actor's perspective the aim is to create a framework model for how a real estate developer can achieve a strategic collaboration with different actors to make the process of reusing construction materials in tenant adaptation projects more efficient.

1.4 Research Questions

The research question can be divided into three different questions;

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• How can a real estate developer create incentives for other actors to engage in a collaboration to facilitate the reuse of construction materials?

• How can a strategic collaboration between a real estate developer and other actors be actualised in order to streamline the process of using reused construction materials?

1.5 Limitations

To be able to conduct the study, some limitations have been made. First and foremost, this study is centred around the real estate developer and how such an actor can collaborate with other actors to facilitate the reuse of construction materials. Also, this study and its conclusions is only based on reuse of construction materials for tenant adaptation projects. Secondly, this study is limited to a certain number of actors. Some actors, such as governmental entities, legal representatives and subcontractors have not been taken into account. Furthermore, the survey conducted was only answered by tenants of the real estate company, Vasakronan, who were located in Stockholm, Gothenburg and Uppsala. Lastly, this study examines a collaboration between actors with regards to a general concept of reused material, i.e. this study does not differentiate on whether the collaboration should be approached differently depending on the materials reused.

1.6 Disposition

This report is divided into six different chapters as seen in figure 1.6.

Fig. 1.6. Visualisation of the disposition of this report

The first chapter is the introduction which aims to give the reader a comprehensive understanding of the problem and why material reuse is important, followed by the purpose of this report and the research questions it is intended to answer. The literature review chapter aims to give the reader an understanding of previous research regarding circular economy, reuse of construction materials, reverse logistics, reverse supply chain and inter-organisational collaboration. Thereafter the method chapter is presented, which shows the reader which approaches the authors have taken in order to obtain the results needed. Furthermore, it aims to clarify the chosen method and how it contributes to increased validity and reliability. This is

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2. Literature review

This chapter will provide the reader with previous research conducted in the field of circular economy, reuse of construction materials and inter-organisational collaboration. Furthermore, this chapter presents previous research on models of reverse logistics and reverse supply chain in the construction industry.

2.1 Definitions

2.1.1 Circular Economy

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Korhonen et al (2018) which besides production and consumption system also focuses on the holistic contribution it has on sustainable societal development. The definition that Korhonen has established takes into account the importance of inter-sectoral, inter-organisational management and governance models (Korhonen et al., 2018).

2.1.2 Reuse of Materials

The general conception about reuse is using the same material in construction more than once and for the same function as it previously had (Yuan & Shen, 2011). Furthermore, reuse of materials can also be defined as “new-life” reuse, where materials does not necessarily need to have the same function as it previously had, but is used as raw material for a new function (Duran et al., 2006). In this report, reuse will be defined in accordance to the European Commission Waste Framework Directive (European Commission, 2010);

“Reuse involves the repeated use of products and components for the same purpose for which

they were conceived” – European Commission 2010

2.2 Circular Economy and Material Reuse in the Construction Industry

The concept of circular economy has gained recognition among policymakers in the construction industry. However, research indicates that the building sector is still mostly discouraging the implementation of it because of certain barriers (Nußholz et al., 2019). Limited research on how circular economy and circular business models can enable the reuse of construction materials has been undertaken, therefore there is a need for expanding the research. 2.2.1 Identified Barriers for Implementing Material Reuse

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around the lack of incentives for designing end-of-life issues for construction materials, a lack of market incentives to aid recovery, the low value of products at end of life, warranty issues of using reused materials and a general lack of knowledge (Adams et al., 2017). Furthermore, besides the general lack of knowledge, a major barrier according to Kartam et al. (2004) is the negative perception the final users have on reused materials, which makes a shift in the end-user’s mentality essential.

Enablers to successfully implement circular economy through the reuse of materials includes feasible logistics, the development of higher value markets and clear business models (Adams et al., 2017). While business models for the reuse of materials in the construction industry has been developed, the implementation of such circular business models has been rather slow (Nubholz, 2019). An issue that has been highlighted in previous research is the absence of market incentives and the lack of incentives for cooperation between different actors, which can be illustrated in the current lack of circular business models. In order to promote closed and circular cycles, it is of great importance to include the entire supply chain and involve all parties from the design stage to the material suppliers and the actors operating in the final stage (Leising et al., 2018).

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• The overall cost of reused materials may exceed the cost of building with new or recycled materials, due to the fact that when reused materials come to the market they may require sampling, testing and certification.

• The second-hand market for construction materials is small. This results in preventing reused materials to be applied on a large scale, due to a lack of recovery facilities and information about reused elements from planned and on-going demolitions.

• There is a scarce amount of companies in the market today that are specialised in deconstruction; designers willing to design buildings using reused materials and contractors willing to construct buildings with reused materials.

Economic challenges such as financial metrics and a return on the investment is therefore believed to be one of the biggest challenges with implementing material reuse in the construction industry (Hart et al., 2019; Adams et al., 2017). Despite the economic challenges arising, several studies show that a circular economy implementation has the potential to reduce the total life cycle costs. (Ellen Macarthur, 2017). Mokhlesian and Holmen (2012) show that the implementation of circular economy in the building sector has the ability to decrease the total life-cycle cost. This is further strengthened by Jung et al (2015) who states that the total costs of the entire value chain structure should be considered in the decision-making process of recovering and reusing secondary materials.

Furthermore, it is important to recognise that in order to achieve economic viability, material reuse must be accompanied with appropriate business models capable of commercialising price competitive products that both meet regulatory standards in terms of quality and safety, but also deliver strong sustainability benefits (Nußholz et al., 2020). The economic viability accompanied with the business model also need to sort out other issues of interest in what value the business model creates for the firm and its customers (Wirtz et al., 2016), and for other stakeholders, in terms of environment and society (Massa & Tucci, 2014).

2.3 Sustainability Effects of Material Reuse

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has mostly focused on the environmental and economic impact of reuse in the real estate and construction sector and has thus mostly focused on two of the three E’s of sustainability (Mohamed et al., 2017).

2.3.1 Economic Sustainability

A study regarding the effects of reusing materials in refurbishment projects, more specific, commercial real estates was conducted in 2018 by Lindholm et al. for IVL (Swedish Environmental Research Institute). The study was a case study based on two of IVL’s own offices in Stockholm and Gothenburg and was focused on what the effects of the renovations of the two offices would be from an economic and environmental aspect and was focused on furniture’s and fixed interior building products, compared to what the effects of the renovation would be with new materials. The study found that the office renovations with reused materials ended up with reduced project costs of 1,4 million SEK for the office in Gothenburg and 1,9 million SEK for the office in Stockholm. The biggest reduction in costs came from reduced purchasing of materials, followed by revenues from sales of used products and then reduced costs for waste management. However, the study also concluded that reusing materials in the two offices resulted in an increase of labour cost by 320 000 SEK for the office in Gothenburg and 350 000 SEK for the office in Stockholm. The reason for the increased labour costs was according to Lindholm et al. (2018) the fact that by using reused materials in a renovation project, the overall wage costs increase due to increased planning work from architects and contractors (Lindholm et al., 2018). Furthermore, since there are many actors participating in an office refurbishment project, Lindholm et al. (2018) believes it is of importance to agree on how the new costs and savings for applying reused materials should be divided amongst the different actors.

2.3.2 Environmental Sustainability

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environmental effects on a building with a large proportion of reused materials compared to newly produced materials. The study showed that the environmental impacts were about 55 % lower with reused materials compared to if the materials were new. Of the materials investigated, the study found that the reuse of clay bricks of roofing clay tiles accounted for the main decrease in environmental impact and that these materials could be transported over a long distance and still be environmentally beneficial (Thormark, 2000). Furthermore, a study made by Nußholz et al. (2020) investigated what the environmental impacts of reusing two different products, namely concrete and glass would be, compared to using newly produced materials. The results suggested a carbon saving potential of 56 tons CO2-eq for glass and 11

tons CO2-eq for concrete.

Besides the potential economic benefits from renovating IVL’s two offices in Stockholm and Gothenburg with reused materials, Lindholm et al. (2018) also came to the conclusion that in the events of renovating the two offices with reused materials compared to new, the decrease in waste would be 18 tons for the office in Gothenburg and 12 tons for the office in Stockholm. Furthermore, the decrease in greenhouse gas emission would be 52 tons CO2-eq for the office

in Gothenburg and 41 tons CO2-eq for Stockholm. This corresponds to a gas emission decrease

of around 60 % per office, compared to new purchased materials (Lindholm et al., 2018). 2.3.3 Equitable Sustainability

As previously mentioned, out of the three E’s of sustainability, equity is the one that has been focused least on with regards to reuse in the real estate and construction sector. However, Mohamed et al. (2017) list four potential impacts on social sustainability due to material reuse:

• Creates distinctive communities: Constructing or renovating a building with a primary focus on creating distinctive communities could have the potential to be more successful and have a more lasting impact with using reused materials.

• Acknowledges underserved and vulnerable populations: Reuse that specifically focuses on the needs of underserved and vulnerable communities can help counter the effects of gentrification.

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2.4 Reverse Supply Chain

According to Guide & van Wassenhove (2002) the definition of reverse supply chain is: “The series of activities required to retrieve a used product from a customer and either

dispose it or reuse it.” - Guide & van Wassenhove, 2002

The definition is further strengthened by Prahinski & Kocabasoglu (2006) who states that the scope of Reverse supply chain also involves the collaboration with other parties and actors (Prahinski & Kocabasoglu, 2006). The concept of a reverse supply chain implies that the life cycle of products and materials do not end when being delivered to the end customer, rather, the end-of-used products can be brought back from the end customers to the suppliers in order for it to be reused, recycled or disposed (Álvarez-Gil et al., 2007).

The implementation of a reverse supply chain requires a large initial investment; however, it also causes strategic importance to companies as well as economic benefits (Álvarez-Gil et al., 2007). The strategic importance can be manifested by the “green image” it offers to the company which may increase the company’s competitiveness in the market and with its customers (Álvarez-Gil et al., 2007).

2.4.1 The Process of the Reverse Supply Chain

Important aspects to consider when establishing a reverse supply chain is which activities that needs to be outsourced versus insourced and how to minimise the costs while maximising the recovering value. When implementing a reverse supply chain, it also is of great importance to make rational decisions about the structure of such a chain. Not all reverse supply chains are identical, however Guide & van Wassenhove (2002) identified that the chain could be divided into five key processes.

Fig. 2.4.1. Illustration of the Reverse Supply Chain. Source: Guide & van Wassenhove, 2002 Product

acquisition LogisticsReverse Inspection and Disposition Reconditioning

Re-distribution

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Product acquisition

The term product acquisition refers to the process of obtaining used products, components or materials from the user (Guide & van Wassenhove, 2002). According to Prahinski & Kocabasoglu (2006), there exists three sources of products: those from the forward supply chain which contains returns of defective or damaged products, those from an already established reverse supply chain, also called market-driven systems; or those from the waste stream. Products that enter the reverse supply chain through the waste stream can either be landfilled or reused due to their recoverable value (Prahinski & Kocabasoglu, 2006). Guide & van Wassenhove (2002) believe that the quality, quantity and the timing of the product return needs to be carefully coped with in order to prevent receiving a huge number of returned products with different levels of quality which further decreases the effectiveness of the process. Retrieving the product efficiently is key to creating a profitable chain while coordinating the collection of the used product through collaboration with distributors (Guide & van Wassenhove, 2002).

Reverse Logistics

Reverse logistics refers to the process of retrieving the product from the end consumer by transporting the products to a facility for inspecting, sorting and disposition (Prahinski & Kocabasoglu, 2006). Reverse logistics contain activities such as; transportation, recovery facility, distribution and inventory management. During this process, the key objective is to assess the condition of the return product and determine the level of quality and use a returned product has (Prahinski & Kocabasoglu, 2006). Prahinski & Kocabasoglu (2006) suggested four pre-dominant groups of product recovery strategies, namely, direct reuse, product upgrade, materials recovery and waste management.

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Reconditioning

If product upgrade or material recovery is decided to be the most appropriate and profitable product recovery strategy in the disposition process, then, the product is transferred to the reconditioning process. During this process the product can be repaired, refurbished or remanufactured. Repair refers to the return of used products to its normal order and refurbishing refers to achieving a product specified quality standard, while remanufacturing aims at reconfiguring a product to reach the same quality standard as a new product. (Gobbi, 2011). However, reconditioning and remanufacturing processes are unpredictable as there exists a large degree of uncertainty in the timing and quality of returned products (Guide & van Wassenhove, 2002).

Re-distribution and Sales

If recovered products are to be re-entered into an external market, reconditioned products and products that are usable can be re-sold to the market (Nuss, 2015). Guide & van Wassenhove (2002) proposes that companies that are considering to re-sell products firstly need to determine whether there exists a demand for it or if such a market has to be created (Guide & van Wassenhove, 2002). If a market has to be created, large investments are required to target potential customers. Potential customers for the products can consist of both purchasers within the existing markets such as original purchasers as well as new customers from different markets for instance such customers who cannot afford new products (Guide & van Wassenhove, 2002).

2.5 Reverse Logistics

In the context of supply chain management, the management of reusing products and materials in industrial production processes, also named reverse logistics, was developed to add value to the current manufacturing processes. (Pacheco et al., 2018). Currently there exists no consensus regarding the concept of reverse logistics (Nikolaou, 2013). Several authors and researchers have defined reverse logistics somewhat broadly as the definition of reverse logistics is sometimes referred to as reverse supply chain. However, according to Guide & van Wassenhove (2002) the terms should be distinguished as reverse logistics is the process of

retrieving the product from the end consumer for the purposes of capturing value or proper

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“the process of logistics management involved in planning, managing, and controlling the flow of wastes for either reuse or final disposal of wastes” – Nikolaidis, 2012

The most recognised definition is however proposed by the European Working Group on reverse logistics who defines it as “the process of planning, implementing and controlling flows of raw materials, in process inventory, and finished goods, from a manufacturing, distribution or use point, to a point of recovery or point of proper disposal” (Nikolau, 2013). There exist two different areas where reverse logistics is applicable; after-sales and after-consumption. Reverse logistics in after-consumption which is the area of most importance in this study considers products at the end of their lifecycle, products that can be reused and industrial waste from production processes. A reverse logistics approach should be adapted when products and materials can be reused and whereas materials will only be disposed of when the total reuse is unfeasible (Pacheco et al. 2018).

An effective management of the activities included in reverse logistics as well as financial incentives is essential for companies to adopt a reverse supply chain system. If the total costs related with the retrieval process exceeds the total cost of new materials or products, firms would have smaller financial incentives to invest in such a system (Prahinski & Kocabasoglu, 2006). The design for a reverse logistics network has to be tailored according to the size and frailness of the products and materials involved as well as the economics of their reuse (Guide & van Wassenhove, 2002). Besides transportation and storage costs, companies should also consider how rapidly the value of the returned products will decline as well as if logistics should be outsourced (Guide & van Wassenhove, 2002).

2.5.1 Barriers for Implementing Reverse Logistics in the Construction Industry

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Table 2.5.1. Identified barriers within reverse logistics literature in the construction industry

Intra-Organisational Barriers Inter-Organisational Barriers

• Higher initial costs of adopting Reverse Logistics

• Risks and uncertainties with using reused materials

• Operational difficulties with providing on-site space for materials

• Lack of awareness amongst organisations regarding the potential benefits of reverse logistics

• Lack of recovery facilities, infrastructure and an established market for reused materials

• Lack of technical support such as building standards and guidelines for reused materials • Lack of financial and regulatory incentives • End-users mindset about the lower quality of

reused materials

• Low costs of newly produced materials • Lack of awareness of reverse logistics in the

construction industry

• Lack of competence and experience in the workforce

2.6 Identified Models in Reuse Management

Previous research made in the field of reuse shows that different management models has been created. In the aspect of reverse logistics and how it can be applied to the construction sector, a study was made by Hosseini et al (2014) investigating the appliance of reverse logistics onto the construction industry with lessons taken from the manufacturing industry. By investigating previous research literature, Hosseini et al (2014) created one model on how to apply reverse logistics in the manufacturing industry and another model for applying reverse logistics in the construction industry. Fig. 2.6.1 and 2.6.2 shows the adaptations of the models created by the authors (Hosseini et al., 2014).

Fig 2.6.1. Illustration of Hosseini et al’s model of reverse logistics in the manufacturing industry. Source:

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Fig 2.6.2. Illustration of Hosseini et al’s model of reverse logistics in the construction industry. Source: Hosseini

et al., 2014

Similarly, as Hosseini et al (2014), another research was carried out by Pushpamali et al (2019) investigating how the decision making of applying reversed logistics in the construction sector could be streamlined. Hosseini et al (2014) argues that the primary reasons for reverse logistics are economic factors and the desire for economic gains. However, Pushpamali et al (2019) argues that the construction sector consumes more substantial quantities of scarce and finite natural resources compared to other industries. Therefore, reversed logistics must be adopted in the construction sector, primarily to reduce the negative environmental and social effects caused by upstream construction activities (Hosseini et al., 2014; Pushpamali et al., 2019). Thus, Pushpamali et al (2019) suggests a model (Fig. 2.6.3) for the decision on reversed logistics which emphasises on both forward and reverse flow in order to maximise its environmental, economic and social benefits. This model also emphasises on the fact that reverse logistics decisions must be made during the pre-construction phase where planning and designing takes place (Pushpamali et al., 2019).

Fig. 2.6.3. Illustration of Pushpamali et al’s reversed logistics decision making model. Source: (Pushpamali et

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A study by Da Rocha & Sattler (2009) investigated how the collaboration between different actors in the construction sector could streamline the process of reusing materials from an old building to a new one. Using a theoretical framework of supply chain management and by conducting semi-structured interviews with different actors in the construction and demolition industry, they opted for a model (fig. 2.6.4) for how the process should be (Da Rocha & Settler, 2009).

Fig. 2.6.4. Illustration of Da Rocha & Settler’s supply chain management of reused building materials. Source:

Da Rocha & Settler, 2009

Although the model shows the different ways and actors that can benefit from reused materials, it is mostly focused on the demolition firm’s perspective and not on all the stakeholders. The study by Da Rocha & Settler (2009) further showed that the reuse of building components is primarily supported by economic and social aspects, such as labour costs of deconstruction and demand for reused materials.

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location that enables all stakeholders to efficiently access, read and update it accordingly (Motamedi et al., 2011). Fig. 2.6.5 shows the model for the levels of information flow required for managing reused construction components between the stakeholders (Iacovidou et al., 2018)

Fig. 2.6.5. Illustration of Iacovidou et al’s, information flow model. Source: Iacovidou et al., 2018.

The model by Iacovidou et al. (2018) shows what type of information that needs to be reported and also when it needs to be reported. Therefore, it could prove to be a valuable tool for managing reused construction components between different stakeholders. By providing all the stakeholders with access to view and update the information, the product data can be followed up in real time throughout the entire product lifecycle (Iacovidou et al., 2018). However, the model demands that all the stakeholders have access to RFID, which may not be the case in practice. Also, it would require unified standards and best of practice guidance (Iacovidou et al., 2018).

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2.7.1 Summary of the Models

Table 2.7.1. Summary of the models presented in previous chapter

Models Reference Positives Negatives

Theoretical Framework Reverse Logistics in the manufacturing industry model Hosseini et al., 2014

Takes into account different ways that materials can be

circular

Mostly adapted to the manufacturing

industry and may not be as

appropriate in other industries Reverse Logistics Reverse Logistics in the construction industry model Hosseini et al., 2014

Takes into account different ways that materials can be

circular

Mostly adapted to the construction industry and may

not be as appropriate in other industries Reverse Logistics Reverse Logistics decision making model Pushpamali et al., 2019 Emphasises that decisions regarding reuse must be taken in the early

stages of designing and planning

Requires an early initiative from the

client to use reused materials,

which may not always be of interest for the

client Reverse Logistics Supply chain management for reused construction components model Da Rocha & Settler, 2009 Gives a comprehensive view on the different ways and actors that reused materials can

go

Solely focuses on the aspects of the demolition firms

Supply chain management

Level of information flow for

managing reused construction components model Iacovidou et al., 2018 Shows in a thorough way when the information needs to

be transferred and what it should contain

Requires that all the stakeholders implement RFID into their daily

routines

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2.7 Inter-Organisational Collaboration

Inter-organisational collaboration refers to the process of collaboration between different organisations with a wide variety of stakeholders facing complex issues they cannot solve separately (Franco, 2008). A theoretical perspective to conceptualise inter-organisational collaboration is inter-organisational domain theory, which emphasises on how collaboration can be a response to inter-organisational problem domains. A problem domain is an entity that is socially constructed, arising when a set of actors becomes dependent on each other as the actions that the actors take in response to a problem occurring can generate potential and unpredictable consequences for the others (Franco, 2008). An inter-organisational collaboration between different actors from different organisations can lead to failure, primarily due to asymmetry of interests and goals (Cabrera & Cabrera, 2002), diverse routines, practices and values (Levina, 2005). However, Gray (1989) argues that the differences in actor’s views, interests and knowledge when facing a problem becomes a valuable asset, which enables the actors to develop a shared understanding of the problem. Furthermore, Gray (1985) believes that the perception of the positive outcome of an inter-organisational collaboration can be increased for certain actors when incentives are provided.

Decision-making problems in a construction project is often caused by the complexity and the high number of involved actors which characterises the construction industry (Yamazaki, 2004). Inter-organisational collaboration in the construction industry refers to relationships between and amongst organisations, such as suppliers, customers, contractors and competitors that are pursuing mutual interest, whilst still remaining independent and autonomous and thus maintaining separate interests (Ebers, 2015). Actors in the real estate- and construction sector can actively reach out and collaborate between organisations, projects and resources and activities that are engaged over time (Havenvid et al., 2019). For instance, in terms of the materials and technologies they use within and across projects, the lessons obtained from within and across projects as well as how they develop new solutions within and across projects (Havenvid et al., 2019). However, these gains can only be actualised when collaborative partners trust each other and create business decisions and plans that are mutually beneficial (Daugherty et al., 2006).

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cooperation among different actors (Ruggieri et al., 2016). By investigating how opportunities of cooperation through inter-organisational symbiosis can enable the development of circular approaches to reuse waste, the authors found that inter-organisational cooperation can in fact facilitate the potential reuse of waste (Ruggieri et al., 2016).

Despite the potential benefits of inter-organisational collaboration there exists several barriers to achieving efficient inter-organisational resource management. Nilsson & Baumgarten (2014) has identified barriers structured into five categories;

o The economic factor includes barriers such as high investment costs, low results due to limited access to material and an unstable market.

o The social factor includes barriers such as a social isolation between organisations, lack of time and resources as well as resistance from external factors such as public entities. o The technological factor includes barriers related to materials such as being unsuitable

for reuse and having quality assurance demands on materials.

o The information related factor contains barriers such as limited knowledge about the market, limited information on potential benefits and a lacking communication between companies.

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3. Method

This chapter presents the reader the methodological approaches the authors have chosen in order to conduct this study. Furthermore, this chapter presents the reader with information regarding the respondents interviewed as well as the actions taken to withhold a high reliability and validity.

3.1 Methodological Approach

When discussing methodological approach, there are two general categories of methodologies; quantitative and qualitative. Quantitative methods are more preferable in research questions such as “how much” and “how many in general to a greater amount”. The aim with such a method is to apply a relationship between parameters and variables to a general population (Brannen, 2005). Qualitative methodologies emerged as a criticism towards quantitative methods (Flick, 2014). Flick (2014) argues that qualitative methodologies are more relevant today because people live a more individualised life than before and society today is more diverse for sub-cultures and lifestyles than before. Therefore, according to Flick (2014), a qualitative research strategy is better adapted to subjective research questions.

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change the strategy of the research depending on the questions that might arise during the research (Saunders et al., 2015).

The primary data was obtained by semi-structured interviews with relevant people in the industry as well as a survey to the tenants. The semi-structured interviews were conducted with determined main questions, with the possibility to free follow up questions based on the answers from the respondents. Semi-structured interviews are best suited for subjective questions where the answers from the respondents are based on their own experience and perception. The choice of semi-structured interviews is done based on the premise that the respondents might have different opinions regarding reuse of materials and a semi-structured approach with free follow up questions thus allows for a deeper understanding of the questions and answers between the interviewer and the interviewees.

To get an understanding of the tenants view on reuse, the most ideal approach in this study was to conduct a survey. There is always a risk for bias and error with a survey, but the procedure used has a major effect on the likelihood that the results will be accurate and in terms with reality (Fowler, 2009). In order to minimise the risk of potentially receiving answers that do not correspond with reality, a survey should have standardised questions (Fowler, 2009). To collect enough participants, the survey was internet-based and sent to a total of 400 companies who are tenants to Vasakronan which resulted in a total of 40 responses. To decrease the risk of bias, the survey was anonymous and the only information the tenants had to disclose was which sector their company operates in.

An adequate approach to complete the primary data is to complement it together with secondary data and then compare the results from the two. Saunders et al. (2015) argues that by complement the primary data with secondary data, it is possible to further argue for the data obtained by the primary data, or even discover new results by triangulation (Saunders et al., 2015). Therefore, secondary data has been obtained by an extensive literature review regarding previous research and literature in this topic. The literature review mostly consisted of peer-reviewed scientific journals and governmental reports.

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new framework model for optimising the management of reused materials and how a strategic collaboration between actors can be incorporated in such a model.

3.2 Choice of Respondents

When choosing respondents to interview, a lot of emphasis was put to conduct interviews with relevant actors active in a tenant adaptation project from different fields within the real estate- and construction industry. This was done due to the fact that by interviewing actors from different fields, it would then be possible to locate common challenges these actors face and how each of these actors can collaborate with each other. Therefore, interviews have been conducted with representatives from real estate companies, architectural firms, demolition firms, waste firms, contractors, material suppliers, logistics companies and consultants specialised in reuse of construction materials. The respondents interviewed represents the following companies; AMF Fastigheter, Castellum, Hufvudstaden, Skanska, NCC, Skanska Hus, Ragnsells, Lotus Maskin och Transport, CS Riv och Håltagning, Byggpall, Interface, Nordström Trä, Moelven, Omreda, Kompanjonen, White Arkitekter and IVL Svenska Miljöinstitutet. Table 3.2.1 shows each representative, their role in the company and how the interview was conducted. The questions asked in the interviews will be presented in the appendix at the end of this report.

Table 3.2.1. List of the respondents and their role in the company

Respondent Type of company Role in the company How the interview was conducted Real Estate Developer

1

Real estate company Head of Sustainability Telephone

Real Estate Developer 2

Real estate company Head of Sustainability Microsoft Teams

Real Estate Developer 3

Real estate company Head of Sustainability Microsoft Teams

Contractor 1 Construction company Sustainable Business

Developer

Telephone

Contractor 2 Construction company Research and Innovation

Coordinator

Telephone

Contractor 3 Construction company Project Manager Telephone

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Demolition and

Logistics Contractor 1 Demolition and logistic company Project Manager Telephone

Demolition and Logistics Contractor 2

Demolition and logistic company

Head of Quality and Environment

Telephone

Supplier 1 Supplier of construction

pallets with specialisation on reused

pallets

Project Manager Skype

Supplier 2 Supplier of textile and

floors

Sustainability Ambassador

Telephone

Supplier 3 Wholesaler of wood Sales Manager Telephone

Supplier 4 Supplier of prefabricated

construction modules

Marketing Director Skype

Consultant 1 Independent consultant

in reuse and renovations

Consultant in reuse and renovations

Telephone

Consultant 2 Independent consultants

in reuse of construction materials

Consultant in reuse Telephone

Architect 1 Architectural Firm Architect Skype

Researcher 1 Research institute

funded by the Swedish government

Project Manager Mail

3.3 Reliability and Validity

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• The respondents were chosen based on their expertise and experience within the real estate and construction sector and also within reuse of materials.

• The interviews were conducted in a semi-structured way in order to have a freer interview with relevant follow up questions that adds to a deeper understanding of the questions and answers.

• The interviews were recorded to ensure the minimisation of loss of information from the time of the interviews to when it is analysed and written down.

• The questions were formulated so that the risk of misinterpretation is minimised. • The secondary data from the literature review was obtained from peer-reviewed journals

and governmental reports.

• The survey conducted was anonymous. This will ensure that the respondents will express their opinion more freely, without feeling that they are going against company policies or jeopardising their own interests.

3.4 Ethics

Every researcher has an obligation to conduct research within the frames and aspects of the ethical standards. Therefore, this research was conducted according to Bryman & Nilsson’s (2011) four principles of research ethics:

• Information. The people participating in a research project shall be informed of the purpose of the research. This includes that the participants shall know that their participation is voluntary and not forced upon. They shall also be informed that they have the right to drop out of the research if they want to.

• Consent. The people participating in a research have the right to decide for themselves the level of participation they wish to have. They can themselves choose not to answer a question if they do not wish to.

• Confidentiality. The personal data from the participant will be treated with the utmost confidentiality. This is to prevent unauthorised people from getting access to their personal data.

• Use. The empirical data obtained from the participants will only be used for the purpose of this research.

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4. Results

This chapter presents the reader with the empirical findings obtained from the interviews and the survey conducted. The empirical findings in this chapter is focused on the barriers as well as the incentives required to implement material reuse and participate in a strategic collaboration for material reuse.

4.1 Current Business Models Within Reuse of Construction Materials

To obtain an overview of the present approach of how companies within the real estate- and construction sector works with material reuse and identify potential difficulties with fully implementing a circular approach to reuse, the respondents were asked about their company’s current business model related to material reuse.

4.1.1 Real Estate Developers

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“Focus should be emphasised on constructing and designing to avoid the need to reuse materials, rather than focusing on how to reuse materials. Constructing buildings with a long-term perspective will diminish the need for demolition and reuse of materials.” - Real

Estate Developer 3

4.1.2 Contractors

Out of the three contractors interviewed, two of them are currently developing their business models to implement reuse of construction materials on a larger scale. Contractor 1 mentions that two business models are in progress, however the respondent could not disclose information on the content due to them being in an early testing-stage, only that they differ in two important aspects: purchasing strategy and quality assurance. Unlike previous respondents, Contractor 2 reveals in the interview that the company has an internal digital platform where they can share leftover materials from their own construction sites which can further be reused in other of their construction projects. In terms of quality assurance, the company is currently developing methods to assure the quality of the reused materials, according to the respondent samples of materials are sent to RISE (Research Institutes of

Sweden) for quality assurance.

4.1.3 Demolition and Logistics Companies

Demolition and Logistic Contractor 2 that was interviewed has a fully established circular business model for reusing construction materials. The company has a subsidiary which sells reused construction materials to third party customers. Demolition and Logistics Contractor 2 mentions in the interview that the company and its subsidiary is responsible for dismantling, making quality assurance of the materials and then transporting it to their recovery facility. The company usually plans ahead to match a certain demolition process of a building with a construction process that is going on at the same time, to be able to reuse the materials from the demolition. The company has also applied an own climate calculator to determine and present how much CO2 emissions can be saved by reusing certain construction materials to the client.

Furthermore, the subsidiary company is not only bound to the parent company itself, but also receives materials from external companies and actors.

4.1.4 Suppliers

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contractors making a request to the suppliers that they want their supplies delivered through the company. The supplier then purchases pallets from the company and delivers their goods on these pallets to the construction site. Once the pallets have been used, they are collected on the construction site and purchased as well as brought back by the company for quality assurance and are further restored if required. The model is based on being non-profitable to encourage a circular implementation of reuse, thereby the supplier gets full coverage for the pallet independent of its condition when being purchased back.

Supplier 2 has an established circular business model in their branches in the United Kingdom and in the Netherlands. In the interview, Supplier 2 mentions that they are currently investigating different circular business models in Sweden. However, there is currently no established model for the Swedish market. As of today, the business models that the company uses for the Swedish market consists of partnering with a third-party company in the Netherlands, the same third-party company that the Dutch branch partners with. The floor contractors dismantle the textile rugs which are then transported to the third-party company in the Netherlands which is further responsible for restoring, stocking and then selling the material to a new customer, which in some cases is the original customer. The third-party company also rates the condition of the textile floor which enables the end-customer to choose which quality they prefer. Similarly, Supplier 4 mentions in the interview that they first and foremost work with reuse internally within the facility. Supplier 4 mentions that there is usually a contractor between them and the real estate developer whom the supplier works together with. Additionally, Supplier 4 mentions that they are developing a strategy to bring back the materials for reconditioning more effectively. However, this alternative is considered as the last prioritised option, since reusing internally within the facility decreases logistical demands.

4.2 Construction Materials with the Highest Potential to Be Reused

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mantle it back on, ventilations channels because, according to Contractor 1, they have been standardised since the 1960’s and do not need to be modified substantially. Other materials such as steel and concrete are mostly mentioned because of their environmental impact upon production and would thus be the best material to reuse from an environmental standpoint.

Figure 4.2.1. Materials with the highest potential to be reused according to the respondents.

4.3 Barriers for Implementing Reuse of Construction Materials

4.3.1 Incentives

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Some respondents claim that the environmental benefits that arise with reusing construction materials are crucial and should act as the most important incentives. Therefore, respondents have emphasised that it would be beneficial to create further incentives by demonstrating a CO2

emission consumption for each material which can be reused, contrary to the CO2 emission

consumption of buying newly produced materials of the same kind. During the interview with Supplier 2, the respondent mentions that the company has goals to be climate neutral by the year 2040. Because of the company goals, they are inclined to continue with the present business model for reusing textile floors despite it not being economically feasible today.

“It is acceptable that it costs the same or more right now until the process for reuse has been refined” - Supplier 2

However, many agree that despite the environmental benefits, material reuse cannot be implemented if there is no economic feasibility with it. Both of the reuse consultants interviewed mention that one way to tackle the economic concerns is by adding value to properties that have reused construction materials. However, they suggest two different means to add value to the property. Consultant 1 and Architect 1 suggests that that an office space that has been built of reused construction materials should lead to a higher real estate value and a higher willingness to pay for tenants, while Consultant 2 suggests that real estates with reused construction materials should receive environmental certifications which thus adds value to the real estate and creates incentives for the tenants.

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involvement of authorities may lead to bureaucracy. However, other respondents believe that a combination of legal requirements and incentives can promote a circular economy and encourage the use of secondary construction materials.

4.3.2 Logistics and Recovery facility

A big challenge that was highlighted during the interviews was the issue of logistics and storage. The process for intermediate storage of materials that is indented to be reused by real estate developers is similar to each other. First and foremost, all respondents within the real estate developing companies mention that materials which will be reused are normally stored in the existing facility that is being rebuilt. If no such storage exists, the materials are stored in their own facilities nearby. However, a challenge with this according to the respondents is that it is difficult to find such intermediate storage, especially in central areas. According to Real Estate Developer 3 there exists no free storage in their facilities in central areas due to them having a higher market demand and is therefore fully leased by the real estate owner with no available space. A challenge arising concerning the logistics according to Real Estate Developer 2 is that there should exist large volumes of reused materials for it to be financially profitable. This is further strengthened by Supplier 1 who believes that logistics within a circular economy may enable a negative environmental impact due to the material having to be transported an additional time and whereas a low volume of material will enable a larger amount of transports which would not be cost-efficient. As contractors primarily work with construction materials on construction sites Contractor 1 mentions that questions arise concerning how leftover materials can be transported from one construction site to another and also emphasises on the importance of the quantity of material.

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Consultant 2 mentions in the interview that one possible way to solve the issues of logistics and recovery facility could be by demolition or waste companies expanding their services to also include transport and recovery facility. However, according to Demolition and Logistics Contractor 2, the logistics of material reuse which includes dismantling the materials, requires competence and experience for it to be handled efficiently. Waste Contractor 1 mentions in the interview that despite the fact that they today do not actively work with reused construction material, they do have the capacity to in theory be able to place containers on the construction site where the demolition firms place all the materials which are then transported and possibly also stocked by the waste contractor. However, according to Waste Contractor 1, there has to exists a sufficient market and economic feasibility for them to engage in such a collaboration.

“It could be as standardised as the process with construction waste is today, as long as there is an economic feasibility” – Waste Contractor 1

Demolition and Logistics Contractor 1 states that if they should expand their services to also dismantle, transport and store products, it requires for them to have a recovery facility to hold. Furthermore, a new customer for the dismantled products has to be ensured before the dismantling process begins. According to the respondent this is vital to ensure that both economic and time feasibility is maintained within the project.

A way to tackle the concerns regarding quantities and the low market for reused materials is to increase the incentives amongst actors by increasing their knowledge regarding the economic effects of reused construction materials, according to Researcher 1. Furthermore, Consultant 2 suggests that by planning to reuse at an early stage of the planning process and making an inventory of the real estate owners internal existing stocks could increase the quantities and raise the market for reused materials. Implementing an electronic register of the properties and their inventory, similar to what they have in the Netherlands, that contains information such as age, characteristics and quality could improve the inventory and demolition process, according to Waste Contractor 1.

4.3.3 Quality Assurance and Warranties

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produced materials should be the same for reused materials. The respondent believes that it is of great importance that quality assurances which are relevant to reuse construction materials are created, to ensure a form of safety for the customer. A challenge with this according to the respondent is that a guarantee for newly produced material is associated with it being expected to last for a number of years, while this might be more difficult to do for reused materials. The respondent means that a guarantee for reuse should focus on the characteristics of the material and on guaranteeing a certain level of quality, rather than guaranteeing that it will last for a certain number of years. According to the contractors, challenges also occur for materials that have to be CE marked, which can be difficult to find amongst former components, which complicates the purchasing process of materials.

When managing reused construction materials, making sure the withhold the quality standards issued by regulations is essential. In the interview with Consultant 2, the respondent mentions that eight parameters can be used in determining whether the material is suited for to be reused or not, they are; demand, ability to dismantle, quantity, age, condition, form, foresight and

function. When interviewing the real estate companies, Real Estate Developer 1 and 2

mentioned that their quality assurance on materials is made by hiring a third-party consulting company that performs the quality assurance. The same issues with warranties are mentioned by Contractor 3, where in the interview, the respondent mentions that in order to set a warranty time from contractor to developer, the same warranty time must be set from supplier to contractor.

When being asked about solutions for streamlining the process of quality assurance concerning reused construction material, Real Estate Developer 2 mentions that there exists no building product requirements and standards for circular material today as there exist for newly produced materials. The lack of standards and product requirements puts a restraint on the real estate developer to follow up and measure the requirements that have been set on the contractors. The respondent therefore believes that product declarations and standards for circular materials must be established in order to more easily ensure quality of the reused materials.

4.3.4 General Perceptions of the Tenants’ View on Material Reuse

Reuse of Construction Materials A study on how a strategic collaboration can facilitate the reuse of construction materials Dana Trabulsi & Milan Sofipour

Reuse of Construction Materials

A study on how a strategic collaboration can facilitate the reuse

of construction materials

Dana Trabulsi & Milan Sofipour

Master of Science thesis

Abstract

Acknowledgement

Examensarbete

Sammanfattning

Förord

Table of contents

1. Introduction

1.1 Background

1.2 Problem Formulation

1.3 Purpose

1.4 Research Questions

1.5 Limitations

1.6 Disposition

2. Literature review

2.1 Definitions

2.2 Circular Economy and Material Reuse in the Construction Industry

2.3 Sustainability Effects of Material Reuse

2.4 Reverse Supply Chain

2.5 Reverse Logistics

2.6 Identified Models in Reuse Management

2.7 Inter-Organisational Collaboration

3. Method

3.1 Methodological Approach

3.2 Choice of Respondents

3.3 Reliability and Validity

3.4 Ethics

4. Results

4.1 Current Business Models Within Reuse of Construction Materials

4.2 Construction Materials with the Highest Potential to Be Reused

4.3 Barriers for Implementing Reuse of Construction Materials