Review of Material Passports and Their Application in Industrialised Construction: Enhancing Material Circularity in Construction

Abstract

Construction industry largely produces long-life, unique, and inflexible products; and combined with dispersed supply chains, it makes material tracking difficult. Thus, to achieve a circular economy (CE) in construction, there is a need for managing material information at the asset level to support reuse and recovery. This study explores the solutions for a CE in construction, and adopts a critical review, and a systematic search and review process. Initially the critical review for CE solutions revealed that maintaining authentic material information via material passports (MPs) and adopting industrialised construction (IC) for resource efficiency and flexibility are the key actions for CE implementation. As initial findings suggested the implementation of MPs in IC as imperative for a CE in construction, it was deemed necessary to develop a framework for MPs’ creation and management in IC. Thus, a further critical review was conducted to explore MPs and IC in detail, and a systematic search and review process extracted the actual information that goes into MPs, which was further categorised under various IC lifecycle processes at different stages of lifecycle, to present the incorporation of MPs into IC. The knowledge of MP processes and information in IC from this review is the vital component for the development of a necessary information management framework for MPs. This study can also be a basis for further research on the application of digital technologies and managerial actions required to realise operational MPs in IC, which is required for material circularity in construction.

1. Introduction

The construction industry is one of the biggest consumers of raw materials and generates a significant amount of waste. The construction industry uses 35% of the extracted raw materials [1]. Just the demolition waste amounts to 30% of the solid waste globally [2]. On top of that, the construction industry is also responsible for 38% of the global energy-related CO₂ emissions [3]. These necessitate sustainability actions in construction, and the circular economy (CE) has been identified as the way to increase sustainability in construction [4]. Through resource efficiency and waste management, the CE can lead to sustainability in construction and a reduction in CO₂ emissions [5].

The most prominent definition of a CE provided by Ellen Macarthur Foundation (EMF) describes a CE as a restorative and regenerative industrial system by intention and design. The adoption of a CE means eliminating waste through superior design and exclusion of toxic chemicals impairing reuse. A CE requires making use of renewable energy in most cases, and the business models adopted need to align with CE principles [5]. Materials need to be at their highest utility and value possible at all times [6] and should be recirculated through processes like maintenance, reuse, refurbishment, remanufacture, recycling, and composting [7]. Kirchherr, et al. [8] based on a literature review have found common actions for CE to be 4Rs, namely, reduce, reuse, recycle, and recovery. Potting, et al. [9] has suggested a framework labelled the 10Rs including additional actions, namely, refuse, rethink, reduce, reuse, repair, refurbish, remanufacture, repurpose, recycle and recover. The list above mentions the least resource-intensive action first, followed by actions that require more resources than the prior. That makes ‘refuse’ the least resource-intensive action and ‘recover’ the highest resource-intensive action. The EMF has also put forward a framework called ReSOLVE for CE strategies, which is an abbreviation for regenerate, share, optimise, loop, virtualise, and exchange. The two frameworks are the prominent ones among all and include all the required actions leading to circularity [6].

Studies have highlighted that the circularity actions like the ones mentioned above can only be achieved if there is the sharing of information about products and processes [10,11]. Honic, et al. [12] and Munaro, et al. [13] mention that the lack of such information at the end-of-life stage hinders the adoption of a material for circular use. Material information is necessary for the operation and maintenance of assets to maintain utility, and necessary to decide the suitable course of action among the 10Rs above for any material at its end of life [14,15]. Therefore, a system capturing and managing information throughout the lifecycle of the asset is necessary [16]. A material passport (MP) is such a tool for material information management [13,17]. In addition to the above, other basic CE actions like the elimination of waste and toxic materials through selection and design, and the use of an efficient resource production process can be achieved through the adoption of industrialised construction (IC) [18]. IC comprises both prefabricated and modular construction, which are the necessary ways to achieve flexibility in design and use for circularity in built assets [6,19]. Thus, material passports (MPs) and IC are the imperatives for a CE in construction industry, which points to the apparent need for study exploring the application of MPs in IC and develop a framework guiding the creation and management of MPs in IC. As the initial step and key component of the framework, a comprehensive list of information to be included in MPs has been developed and shortlisted according to the IC lifecycle processes that generate or update the information. The information related to MPs has been listed by other studies previously. Munaro and Tavares [20] have listed MP-relevant information for newly constructed buildings, whereas Çetin, et al. [21] have listed MP-relevant information for existing buildings, while both lists are for generic buildings. Although Kedir, et al. [16] have listed information for MPs in IC, their list lacks a complete list of information, which needs to be captured and managed throughout the lifecycle, including the operation and maintenance stage. Building on existing works, this study intends to develop a comprehensive list of information for MPs of IC assets covering the whole of their lifecycle. The list of information is one of the key components and the initial step for developing an MP framework to create and manage MPs to facilitate circularity in built assets.

The next section (Section 2) further explains the key requirements for material circularity in construction and the importance of a review on MPs and their application in IC. Section 3 describes the research method adopted in undertaking this review. Section 4 elaborates on MPs and their necessity for the CE through a critical review. Section 5 critically reviews IC features and lifecycle stages. Finally, Section 6 explores the application of MPs in IC and offers a detailed list of MP information required throughout IC lifecycle stages. The final section offers the conclusion and implications of this review.

2. Issues and Solutions for Material Circularity in Construction

A circular economy (CE) in construction is a way for preventing new resources’ extraction, while optimising materials already in-use within the construction industry. The relevant circularity actions are not limited to recycling and reusing, but also include reducing the overall need for resources in construction [22,23]. However, the literature analysis by Norouzi, et al. [1] revealed that recycling, waste management and sustainable development occurred more frequently than other equally important aspects of reducing and reusing of materials [24] and design considerations [25]. Regarding material management for a CE, the main goal is the reduction in use of finitely recyclable construction materials, while subsidiary actions like effective and cost-optimised dismantling, sorting, transportation, and recovery are also essential [26,27]. Nevertheless, the implementation of a CE in construction requires specific actions pertaining to the nature of the construction industry.

The most contrasting aspect of the construction industry compared to industry in general is the long life of products, disallowing the business models of short- or medium-lived products such as ‘taking back options by manufacturer’ [25]. Another specific aspect is the industry is fragmented in the form of different projects carried out in their own silos, inhibiting the material flows between such projects and making it difficult to track the provenance and ownership of the material [28]. In the construction sector, mostly the products created are unique, resulting in complex supply chains around each project. The uniqueness of a product leads to companies focusing on short-term goals rather than having a long-term view of sustainable deconstruction and the reuse of materials at the end of their lifecycle [29].

Therefore, the decentralised production system, building assets with a long lifecycle, involving multiple stakeholders with varying responsibilities and ownership throughout the lifecycle of a single asset, is typical in the construction industry. Material circularity for CE implementation requires that the constructed built assets be the source of construction materials. However, such built assets are unique, as each asset has its own different design and construction details. The above issues hinder material circularity by causing a lack of uniformity in materials and processes adopted and complicating the tracking of material provenance throughout the lifecycle [30]. Two necessities identified from the literature to tackle issues hindering the implementation of a CE in construction are discussed further in the following two sub-sections.

2.1. Need for Material Information and Material Passports

Circular economy (CE) implementation starts at the design stage [31], with design setting the path for various circular strategies to be implemented at later stages of the lifecycle till end-of-life deconstruction [32]. One such action is the plan for the reuse of materials at their end of life from the early design stage. The building can be designed considering future deconstruction at the end of life or adaption for modified use prior to deconstruction [23]. The buildings designed or materials incorporated can be analysed using the Life Cycle Assessment (LCA) method to understand their environmental impacts and make design decisions [14,33]. Achieving circularity would require considering the whole of lifecycle right from the design stage to construct and operate a building as a material bank [31,34]. While the material information about any newly constructed building is collected early on from the design stage, information about materials of already existing buildings is also required to ensure their next use [14]. Information about deconstruction, disassembling, storage and processing requirements for their next use should be known for the adoption of such materials in future design and construction [28].

In addition to implementing circularity actions at the building level, the circular flow of materials at a regional scale is also essential to achieve a CE in a built environment. For such circular flow to happen, it is imperative to conduct Material Flow Analysis (MFA) at a regional scale, determining the potential urban metabolism and planning accordingly [28,29,35]. This involves understanding the relationship between entities involved while considering them as systems and estimating the effect of local/regional material flow and waste management [14]. Modelling the flow of materials (input–output) from system to system allows for CE evaluation and effective implementation at a macro scale [28]. Therefore, calculating the quantity of material required for MFA and subsequent modelling is fuelled by authentic material information.

In all above cases, the material information needs to be maintained throughout the lifecycle of the asset. Second-hand materials in construction are unique because of the difference in production and/or use of the materials. This results in complexity for material reuse because every material’s unique information should be known to decide on further actions. Thus, it is necessary to manage the unique information for each material that is feasible for another use in their stand-alone form for each asset to realise a circular material flow at a regional level. Material passports (MPs) has been identified as one such tool for information storage and analysis. MPs facilitate different processes discussed in this sub-section. For example, MPs enable material identification [36], the analysis of environmental impacts [14,23], and the tracking of material utility throughout the lifecycle of the building [34]. The development of MPs for any built asset starts from the design stage as the information about the assets begin to finalise, and such information has to be updated throughout the lifecycle to achieve the circularity actions intended [20,21]. MPs will be discussed further in later sections.

2.2. Need for Industrialised Construction

Managing of supply chain processes including production or product type is also necessary for CE implementation in construction. Managing of those processes is necessary to solve issues such as a lack of standardisation [37], and short-termism among supply chain actors [14,28]. Additionally, buildings that are adaptable and flexible to changes in use have a longer service life and can allow for any modification in an asset’s use in a resource-efficient manner [25]. Moreover, the initial production process of a building material itself should be as resource-efficient as possible [38]. Prefabrication or modular construction has been suggested as a suitable method for flexibility, adaptability, resource efficiency and easy deconstruction [6,28]. It would also allow for the standardisation of the building materials. Therefore, industrialised construction (IC), comprising both prefabrication and modular construction, should be adopted as the way forward for a CE in construction. In addition to the above features, IC also facilitates supply chain integration resulting long-term supply chain relationships in construction [39].

In addition to the facilitation in supply chain processes, IC also favours information management. With the standardisation and integration of the supply chain, IC develops a predefined product platform for production, which can be the source of information about standardised products and processes. The integration of a supply chain also enables collaboration for the effective collection and sharing of information [16,34]. The development of MPs is largely eased by the presence of these information-readying mechanisms. Furthermore, the availability of authentic, complete information supports better lifecycle management, as the planning and conducting of maintenance works are resourced by credible information. Therefore, robust information management through MPs and the adoption of IC are a prerequisite to a CE in construction. Issues in CE implementation have been mapped with CE actions that can solve these issues and further such actions of key solutions of MPs and IC as realised in the literature. A mapping of issues with possible CE actions facilitated by MPs and IC is presented in Figure 1. CE actions are colour coded in Figure 1, and lines connecting to issues that can be solved through an action are coded with colour representing the action. A similar colour-coding approach is taken to present the actions that can be achieved through the adoption of any solution. The adoption of MPs in IC will be discussed further in later sections.

3. Research Method

The literature review type adopted for this study is a critical review [40]. The critical literature review started with reviewing the seminal literature on the CE, and the CE in construction using a relevant keywords search in Scopus and Google Scholar. As the review progressed, a snowballing approach was taken to select further keywords and studies from the review of the literature obtained from the initial search. The keywords search for critical review about any topic started with the ones naming the topic itself. For example, a search regarding the CE and construction included the keywords “circular economy”, “construction industry” and “built environment”. Similarly, a review for IC involved keywords such as “industrialised construction” and “circular economy”, and later keywords such as “resource efficiency”, “material passports” and “information flow” were added as initial results pointed to the use of those words. The highly cited studies from the initial results and the literature commonly cited by highly cited studies were selected as the seminal ones to begin the review. Critical review included the review of both the academic and grey literature. Grey studies were selected based on the ones cited in academic ones. In addition to the critical review, a systematic search and review was conducted for shortlisting the literature related to MPs for the CE in construction [40]. Using the systematically obtained academic articles, manual qualitative content analysis was undertaken to list the information related to MPs. The research method adopted for this review is presented in Figure 2.

The background literature review, as discussed in Section 2, established the need for MPs and IC for material circularity in construction. Independent critical reviews on MPs and IC further identified circularity features and specific processes for MPs and IC, which are presented in Section 4 and Section 5, respectively. Simultaneously, following a systematic search, a list of MP-relevant information was obtained from general MPs in the construction literature (see Figure 3). This was later arranged according to IC lifecycle processes to specify MP management and application in IC (see Section 6).

Figure 2. Overall research method.

Figure 2. Overall research method.

Regarding the systematic search for MP-relevant information, the search strategy as suggested by PRISMA methods checklist was adopted [41]. The eligibility criteria set was that the study should be a published paper discussing the developing and implementation of MPs for a CE in construction. Papers published until December 2024 were taken reviewed. The paper types were restricted to research articles, review articles, conference proceedings, and book chapters. The Scopus database was selected as the source for this review, and the search string was entered as “Circular economy” AND (“Material passports” OR “Material Banks”) AND ({buildings} OR Construction OR “built environment” OR {building sector} OR {building industry}). The keyword search was limited to title, abstract and keywords of the article. The Scopus database was adopted because it is the largest database, and generally provides more articles than any other database [42]. The literature related to the CE and MPs were mostly published in recent years, i.e., in and after 2019. As the Scopus database maintains a wider coverage of all articles among the latest publications, including all paper types, conducting a search in it would suffice to produce an exhaustive list of articles [42].

At the time of the search (in December 2024), the total number of articles obtained was 98. This was obtained after an initial screening of paper type and publication year. The selection of papers from the initial list was performed based on a review of the abstract to specifically short-list papers meeting the eligibility criteria mentioned above, i.e., those about MPs for a CE in construction. Finally, after reviewing the abstracts of all 98 papers, 23 articles were selected to undertake qualitative content analysis to list out MP-relevant information. The outline of the systematic search and review is shown in Figure 3. The content analysis was manually conducted, and the selected papers were thoroughly read to list out information that authors believed should be included in MPs. The information list developed from the review of earlier papers was populated with newer information from successive paper reviews. When information was repeated in a new article, a citation was added on to the prior listed information. The authors separately reviewed the literature, and the information list was critically analysed to validate results and compile a final list of MP-relevant information.

4. Material Passports for Circular Economy

MPs, as mentioned in Section 2.1 and Figure 1, are the tool for managing material information throughout lifecycle of the asset. Material information maintained right from the early stage of the asset lifecycle allows us to keep a record of a material’s provenance and keep track of its utility throughout its lifecycle. Authentic updated records of information create conditions to consider built assets as material banks for later trading and use of materials. Further MP features abetting circularity and key considerations for the material and information flow for MPs are discussed below in this section.

4.1. Circularity Features of Material Passports

MPs are digital datasets consisting of information about materials [30]. An MP of a material contains necessary information, ranging from its identification details to its chemical composition, assembly and disassembly procedures [15], determining overall CE potential and future pathways for the next use of a material [43]. MPs store and track all circularity-related information [21], and should be available and updated as required throughout their lifecycle [44]. MPs not only include material condition information, but also the process information of material reuse and recovery [45]. Generalising information based on material types such as wood, plastic, and metal will not be sufficient to maintain the utility required to ensure the reuse of components [30].

Material data should be generated and managed at hierarchies of material, component, system, and building levels [46,47], implying that the word ‘material’ means an asset at any level that can be taken into the next use in its stand-alone form. Among these hierarchies, materials and components are the fundamental elements for which the information is created, and for hierarchies other than these, it would be the accumulation of information from the former two. Thus, MPs created for these two hierarchies (materials and components) are the basic building blocks of information for MPs of higher hierarchies. While the information about materials and components facilitates decision-making and selection for the next user, information about a system would also include information related to resource- and energy-efficient operation, for example, HVAC, lighting, water usage, waste management and so on. While such information regarding operation should be considered to achieve overall circularity, the key objective of MPs is achieving material circularity. MPs contain information that is both quantitative and qualitative, collected at different stages. Quantitative information is generally information involving numbers like dimensions and material composition, whereas information about handling, assembly, disassembly, safety, and maintenance instructions is qualitative information [12,16].

At the initial stages of the project, MPs of the building materials supplied by the manufacturers provide information about material properties and manufacturing processes, which makes MPs useful as design optimisation tools to compare the circularity and environmental performance of different design options [21,48]. Information in the early design stage is useful to minimise the resource impact during the primary use and to assess the potential for reuse [16]. With information beforehand, it also allows us to foresee the lifetime of the asset and set sustainability targets accordingly [20]. Actual MPs of the materials embedded in the assets are eventually finalised after either the procurement or construction of the asset. Such MPs would also act as lifecycle management tools as they help to keep a record of information about maintenance renovation and repair, keeping track of a material’s utility throughout its lifecycle [21]. MPs provide information to conduct the circularity assessment of assets, as a complete set of MPs of all materials and components within the assets would include all the information required for such assessments [49]. With all the information stored in MPs, the buildings can be considered as material banks, where buildings act as storage for materials and components for multiple uses. The information about existing materials enables the next use at the end of each lifecycle [20,50]. Different options for the next use of a material cascading from reuse to repair, refurbishment, and recycling is decided using the cascade potential determined based on information from MPs [15,20]. In the end-of-life stage, MPs can support the accurate estimation of waste quantity for planning demolition, waste management and its logistics [51].

MPs also enable information flow between stakeholders, who are part of the asset at different stages of its lifecycle. Information generated by actors at the early stage of the project is utilised by stakeholders at later stages of the lifecycle [30]. MPs, as the body of information of every material entity, would further be a basis for city/region-wide non-virgin materials’ cadastre [51]. Therefore, MPs would not only ensure the quality of materials by enabling to maintain the highest residual value, but also upon accumulation at a city-scale would allow us to keep track of the supply of such recovered resources required for MFA and to keep track of the metabolism of cities to realise a CE at a regional scale [52]. This would also help to meet and nurture more demand for non-virgin materials. Moreover, city-wide information will help with waste reduction overall while also reducing the eco-footprint resulting from the waste management process [43]. The next section discusses differences in material flow and information flow patterns, and types of information to be dealt with at different lifecycle stages.

4.2. Material and Information Flows in Built Asset’s Lifecycle

The MP information is created and updated at different lifecycle stages. Considering the distinction between the material flow and information flow at different stages, the lifecycle stages can clearly be distinguished into three stages: design and construction, operation and maintenance, and end of life. As the material flow direction varies at different stages of the lifecycle, similar directions would be followed by the flow of information about materials. These different lifecycle stages are considered based on material flow and information flow, and are distinct based on the different information types to be managed for MPs at these lifecycle stages. The different categories for information types are taken from previous work [53]. Previous categories of information suggested by Munaro and Tavares [20], Çetin, et al. [21], and Kedir, et al. [16] were reviewed and a further comprehensive classification for MP-relevant information was put forward in [53]. Different categories of information thus obtained are general, health and safety, environmental, design, construction, operation and maintenance, and next use. The ‘General’ category comprises information related to material identification, dimensions, and properties, basically all-purpose information about the materials. The ‘Health and safety’ category comprises information about safety aspects of material storage, handling and use. The ‘Environmental’ category includes information related to measuring and managing environmental impacts caused by the production and use of the material. The ‘Design’ category includes information that is useful for design process, while the ‘construction’ category includes information required for the production and construction process. Similarly, the ‘operation and maintenance’ category includes information that is necessary for operation and maintenance works, and ‘next-use’ comprises information that is necessary to decide and act on another suitable use of the material at the end of a particular lifecycle.

Table 1. Different lifecycle stages and related material information types.

Lifecycle Stages with Distinct Information Flow	Material Information Type Generated and/or Updated	MP-Relevant Information Flow
Design and construction	- General - Environment - Health and safety - Design - Construction - Operation and maintenance - Next-use	Material passports added
Operation and maintenance	- Environment - Operation and maintenance - Next-use	Material passports added and dispersed
End-of-life	- Next-use	Material passports dispersed

lists different lifecycle stages and respective MP information flow patterns and categories.

The sources of information contained in MPs are diverse. They could be external third parties such as manufacturers, and suppliers, or can be created by teams working within the project. The collecting and creation of information also takes place at different stages of the lifecycle. Some information that is created at earlier stages of the lifecycle is updated in later stages of the lifecycle. During the design and construction stage, information about different materials is either created or is collected from the manufacturers and suppliers. For the materials designed and constructed within a project, information comes from in-house project teams. Information keeps adding up during this stage and MPs of those materials and products are created. In the operation and maintenance stage, the material and components might be both added and removed from the existing asset, and so is the information. The information about newly added products is used to create their MPs, whereas for a material removed from the assets, its MP are handed over to the new user. Finally, materials and components are dispersed in the end-of-life stage. Therefore, their information is also transferred with their MPs.

During the design and construction stage, general information about the materials such as identification, dimensions, physical properties, composition, etc., is developed through the design or collected from the manufacturers/suppliers. In addition, information about environmental performance, health and safety information about a material’s usage and handling, and instructions for construction and installation, are also generated during the design and construction stage. This stage also includes the development of operation and maintenance information, and material next-use information, although the next-use information might be updated in later lifecycle stages. During the operation and maintenance stage, MPs for newly added products are developed as carried out for new materials in the design and construction stage. However, the predominant information dealt with at this stage is operational information of the tracking and updating of environmental performance and the developing and/or updating of operation and maintenance instructions. As discussed in first the paragraph of Section 4.1, information related to resource-efficient operation is part of the information managed, but generally the information related to maintenance leading to the update of information about building components is emphasised more for the transfer of materials to the next user. Such materials’/components’ information also includes the developing and/or updating of next-use information of materials added or that have undergone maintenance work. Finally, in the end-of-life stage, the information to be managed is what is necessary for deconstruction and what facilitates the next uses of materials. The material and information flow patterns along with the information types at different lifecycle stages are presented in Figure 4.

Figure 4 is the diagrammatic representation of the above discussion in this sub-section and the contents of Table 1. Three lifecycle stages with distinct variations in material information flows have been presented, where the arrows show the direction of the material flow as discussed previously. Letter M represents materials and letter C represents components, two fundamental asset elements for which MP information is generated. The figure shows how the number of materials and components in any built assets, represented here from 1 to n, is accumulated into the asset. The first material (M1) would be added in the “design and construction” stage, whereas the last material (Mn) would be added to the asset in the “operation and maintenance” stage. The dispersion of a material might begin at the operation and maintenance stage, and dispersion is completed during the end-of-life stage. The information types that are either created or updated during each lifecycle stage are mentioned in the part of the figure portioned for that stage.

5. Industrialised Construction for Circular Economy

As mentioned in Section 2.2 and Figure 1, IC is the resource-efficient method of asset delivery and asset operation. In addition, the standardisation of products and processes facilitates the trading and reuse of materials, and an integrated supply chain allows us to keep track of and ensure material quality. Thus, IC stands out as a suitable construction method considering circularity. Further features of IC abetting circularity and consideration for lifecycles are discussed below in this section.

5.1. Circularity Features of Industrialised Construction

Industrialised construction (IC) basically has two main key aspects, the standardisation of the construction process and products [54,55] and the implementation of manufacturing principles in the construction [56]. IC intends to have a continuous flow of production with minimum waste [57]. It involves integrating design and optimisation tools used in manufacturing for construction purposes [19]. An integrated supply chain (design and production process) also reinforces collaboration among stakeholders and vice versa [57]. A long-term supply chain relationship, with advanced supply chain management and logistics, is part of IC [16]. Mass production or repeated production takes place in a controlled environment and on a predefined platform for production [55]. Kedir, et al. [16] describe it as the other way around, i.e., with a predefined product platform being the tool for standardisation, which in turn allows for mass production. There is a general tendency to automate the production process in IC, and also the intention of continuous improvement in the process through feedback between stakeholders [57]. The automation and mechanisation require extensive digitalisation to develop detailed digital models to facilitate the mechanised production [16,58]. Prefabrication is the integral process in IC and a product can be of various forms such as panels, trusses, metal frames and precast concrete [19]. Although there are limitations to customisations in circularity for delivering an entirely unique product, as discussed earlier in Section 2.2, there are many benefits of IC implementation such as better efficiency, safety, and quality [19,56]. Resource efficiency through IC involves not only reducing the extraction of virgin and non-renewable resources, but also a reduction in production waste and the prolongation of the product’s life [18]. IC allows for better traceability of origin and supply chain aspects of the materials as the supply chain is more integrated and transparent in IC [59,60]. The integration and collaboration provide ground to work and decide on non-toxic, renewable and reusable materials for construction [61]. Figure 5 represents different features of IC as discussed above.

Most of the above-mentioned IC characteristics support material circularity. Resource efficiency actions happen majorly during design, manufacturing, and logistics stages of the lifecycle, and as they start early on from the design stage, they can undertake tasks like designing out negative externalities, and preserving natural capital [18]. Having the option to design and select materials well ahead of time allows us to decide on and select the most regenerative option. Apart from that, resource efficiency can also be achieved by ensuring the reusability and recyclability of a material at end of its lifecycle through conscious design. Supply chain collaboration that can be achieved in IC can allow grounds for innovation and adoption for circularity practices [56]. The traceability of products throughout their supply chain can help determine the exact environmental impacts. Digitalisation in IC allows us to virtualise design and managerial processes. Flexibility and adaptability are the key characteristics abetting the optimised use of a built asset while also enabling later the deconstruction and reuse of components [6].

IC, as discussed earlier in Section 2.2, also favours information management. IC needs robust information management to facilitate the core actions of IC. Regarding efficiency and productivity, the information management needs to be capable enough to control production processes to optimise resource use and reduce waste. The bi-directional flow of information between client, engineering, production, and assembly teams is required for the factory-based production of a construction component, and for any customisation required or to define the limits of customisation [62]. Jansson, et al. [58] argues that the scale of predefinition of the product determines the scale of information flow and digitisation required in IC projects. Knowledge and processes within the organisation need to be fully assessed to develop such an information management system and employ digital information and communication technologies (ICTs) for such a purpose [62,63]. The collaboration and close business relations between stakeholders require a sound information flow between stakeholders, which is aided through the digitalisation of products and processes [64]. Therefore, information flow in IC can be maintained based on product platforms, ICTs, and supply chain integration. As discussed previously in Section 2.1, material information is necessary to facilitate circularity strategies. From resource efficiency to the transferring of end-of-life materials to the next owner, information flow among involved stakeholders is vital. Such information flow has been labelled as circular information flow, and MPs have been mentioned as a tool for material information management. In IC, information management to manage the production processes and supply chain also facilitates the circular information flow [16,39]. The exact information for MPs with their origin and use in IC for circularity is discussed in a later section (Section 6).

5.2. Lifecycle Stages of Industrialised Construction

The IC lifecycle differs from conventional construction in terms of priorities about actions to be undertaken for a particular project. A generic construction lifecycle as suggested by the Royal Institute of British Architects (RIBA) plan of work [65] would comprise the following lifecycle stages: planning, design, detailed design, manufacturing and construction, handover and use. However, in IC, the design process in not undertaken from scratch, and selection or customisation is carried out based on existing design and building components. The supply chain and logistics make up a significant part of the work undertaken as the manufactured materials need to be transported and managed to be available as required at a site. With components majorly produced offsite, thorough coordination between factory production, on-site works and logistics management is required [66]. According to Ribeirinho, et al. [66] and Wuni, et al. [67], the project delivery stages with the adoption of IC can be listed as planning, design and procurement, manufacturing and product development, supply chain and logistics coordination, assembly and final building. However, to achieve circularity by ensuring the reuse of materials at the end of their life, MPs once created are to be tracked and updated as required throughout the lifecycle of the asset. Thus, the whole of the lifecycle has to be considered, i.e., considering the operation and maintenance (O&M) stage and the end-of-life stage in addition of asset delivery stages (see Figure 6) to cover the whole process of MP creation and management for the built asset [16]. While the O&M stage is the same as the use stage mentioned in the RIBA plan of work, the end-of-life stage is the necessary addition required for MPs’ update and for the possible creation of MPs for entities to be obtained after deconstruction, as some existing as-built entities might have to be traded in a transformed form. While the initial stage of planning, design and procurement is executed chiefly by the client and consultant, the following two stages of asset production and delivery are conducted through an offsite manufacturing facility [67]. The building elements are then assembled by on-site contractors in the assembly stage and handed over to the end user. The first four stages in Figure 6 fall under the “Design and construction” stage mentioned in Figure 4, while the remaining two are the same.

6. Application of Material Passports in Industrialised Construction

Suitability of IC for a CE has been discussed in Section 2.2. Also, the facilitation provided by IC features to information management has been discussed. While the types of information to be managed might be similar to those in conventional construction, IC features like standardisation, digitisation and an integrated supply chain would enhance the availability and authenticity of information. Similarly, streamlined processes for IC would also enhance robust information capture and management for MPs. As the IC processes vary from conventional construction, the information creation and use would vary in of IC. There might be some adding or removing of some information, and/or the information might be interpreted differently in IC than in conventional construction. To achieve a list of information to be contained in MPs for IC, firstly, the list of information that would generally go in an MP was obtained from a literature review as discussed in Section 3. The MP-relevant information thus listed was further adapted and sorted under different IC lifecycle processes through (during) which the information was generated. Circularity-enhancing features of IC such as resource efficiency, information management, and flexibility are enabled through MP information generated during the IC lifecycle processes.

The list of information developed is presented in

Table 2. Information generated through different lifecycle processes of IC.

Group 1: Executive stakeholder—Client
Lifecycle Stages	Processes	Information	Identifier
Planning and Procurement	Scoping of work [66,67]	Building’s name/type/location [21]	G-1
	Selection of design or building components [16,66,67]	Drawings, dimensions, and BIM models [21,50,68]	G-2
	Selection of materials/product [16,18,67]	Design with material specifications [16,69]	G-3
		Physical properties (dimensions, weight, density, fire resistance, required storage conditions) [13,16,17,20,21,43,49,50,68,70,71]	G-4
		Chemical/material composition [13,17,20,21,30,43,71]	G-5
		Product quantity [21,50,72,73]	G-6
		Toxicity and hazardous substances [13,20,21,50]	H-1
		Product function [16,20]	G-7
	Decision on environmental performance [18]	Environmental performance information (Life Cycle Assessment, Environmental Product Declarations) [12,15,17,48,72]	E-1
		Percentage of renewable materials [16,20,21,49,70,72]	E-2
		Percentage of recycled/reused materials [16,20,21,49,70,72]	E-3
		Embodied carbon [16,49,73]	E-4
		Reuse potential [16,17,20,21,30,49,70,72]	E/N-1
		Recycle potential [16,17,21,30,43,44,49,70,72]	E/N-2
		Disassembly potential (properties, actions, environmental and financial impacts of disassembly work) [43,45]	E/N-3
		Disposal options/decomposability [20,21,49,70]	E-5
		Cost measurement of environmental impacts [49]	E-6
		Sustainability certification labels [16,20,69]	E-7
	Selection of manufacturers and suppliers [66,67]	Components’/products’ commercial name [13,16,20,30,49,70,73]	G-8
		Manufacturer details [16,20,21,30,49,69,72,73]	G-9
		Manufacturing process and techniques [20,73]	E-8
		Manufacturing waste [16,17,73]	E-9
		Product cost [49,50,72]	G-10
		Safety certifications [20,73]	H-2
		Product picture [20,21]	G-11
		Product safety data sheet [13,21,43,44,73]	H-3
		Security information (warning and recommendation) [20]	G-12
		Take-back options [16]	N-1
		Expected lifetime [13,16,20,21,30,49,70]	G-13
		Warranties [16,20,69]	G-14
	Material transportation planning [67]	Handling instructions [16,20]	C/O-1
Group 2: Executive stakeholder—Manufacturing facility
Lifecycle Stages	Processes	Information	Identifier
Manufacturing and production	Manufacturing/ Production [16,66,67]	Manufacturing date [16,20,21]	G-15
		Use/handling instructions [13,16,20]	C/H-1
		Installation and assembly instructions [13,16,20,30]	C-1
		Product code number (unique product ID) [17,21,45,72,73]	G-16
		Product Picture [20,21]	G-17
		Sustainability certification labels [16,20]	E-7
		Safety certification labels [20]	H-2
	Ensuring resource efficiency [18]	Manufacturing waste [16,17]	E-9
		Percentage of renewable materials [16,20,21,49,70,72]	E-2
		Percentage of recycled/reused materials [16,20,21,49,70,72]	E-3
		Reuse potential [16,17,20,21,73]	E/N-1
		Recycle potential [16,17,20,21,73]	E/N-2
		Disassembly potential (properties, actions, environmental and financial impacts of disassembly work) [43,45]	E/N-3
		Disposal options/decomposability [20,21,49,70]	E-5
	Real-time tracing of production process and material information [16]	Embodied carbon [16,49,73]	E-4
		Energy consumption [20,21,47,50,73]	E-11
		Water consumption [20,73]	E-12
		Environmental performance (impact) information [12,15,17,48,72]	E-1
		Material specifications [16]	G-3
Supply chain and logistics coordination	Transportation and storage of materials [18]	Embodied carbon [16,49]	E-4
		Energy consumption [20,21,47,50]	E-11
		Environmental performance (impact) information [12,15,17,48,72]	E-1
Group 3: Executive stakeholder—Contractor
Lifecycle Stages	Processes	Information	Identifier
Assembly	Efficient and safe installation of works [18]	Connection details [13,20,21,30,50,68,71]	C/O-2
		Disassembly potential (properties, actions, environmental and financial impacts of disassembly work) [43,45]	E/N-3
		Disassembly instructions [13,16,20,30,45,71]	O/N-1
		Maintenance instructions [13,16,21]	O/N-2
		Safe handling instructions [13,16,20]	C/H-1
		Works quality assessment [21,71]	C/O-3
		Installation date in the building [21]	G-18
		Position and location in the building [13,20,21,30,50,70,72]	G-19
		Expected lifetime of building [13,16,20,21,30,49,70]	G-20
		Unique building identifier [16]	G-21
		As-built drawings and BIM models [21,50,68]	G-22
	Updating environmental information [18]	Assembly works waste [16,17,71]	E-13
		Embodied carbon [16,49]	E-4
		Energy consumption [20,21,47,50]	E-11
		Environmental performance (impact) information [12,15,17,48,72]	E-1
Group 4: Executive stakeholder—End user
Lifecycle Stages	Processes	Information	Identifier
Operation and maintenance	Material utility assessment [16,18]	Material integrity condition [21,45,68,71]	O/N-3
		Use period [13,20]	O/N-4
		Latest uses/operations [13,20,30]	O/N-5
	Updating of information after maintenance (if any needed) [16,18]	Maintenance instructions [13,16,21,71]	O/N-2
		Disassembly instructions [13,16,20,30,45,73]	O/N-1
		Maintenance/repair log [13,16,20,21,30,68]	O/N-6
	Updating environmental information [16,18]	Operational carbon [16]	O/E-1
		Energy Consumption [20,21,47,50,71]	O/E-2
		Water Consumption [20]	O/E-3
		Operation and maintenance waste [16,17]	O/E-4
		Renovation details [21,68]	N-2
End-of-life	Assessing circularity information [16,18]	Pre-disassembly condition assessment [45]	N-3
		Availability time in future for reuse [21,50]	N-4
		Process data for cascading uses [15,71]	N-5
		Disassembly potential [43,45]	E/N-3
		Disposal options/decomposability [20,21,49,70]	E-5
	Logistics information [16,18]	Disassembled material storage and transportation instruction [13,20,71]	N-6

. The first column consists of different lifecycle stages and in the second column, the processes for each stage are listed. The third column consists of information generated from each lifecycle process. The information list is divided into four parts based on the different chief actors leading the execution of works and information generation as presented in Figure 6. The first group is the lifecycle processes relating to planning, design and procurement where the client is the chief stakeholder. The second is the manufacturing facility presiding over offsite production and management works. The third is the contractor executing onsite works and the fourth is the end user operating and maintaining the asset for rest of its lifecycle.

An identifier for each information piece has been assigned by taking the initial letter of the information category discussed in Section 4.2,i.e., G for general, E for environmental, H for health and safety, C for construction, O for operation and maintenance, and N for next-use. Then a reference number is added to the initial letter to make the identifier unique for each piece of information (e.g., G-1, G-2, H-1, H-2, and so on). The reference number starts from one for each category (e.g., H-1, H-2, H-3, and so on). Information involved in more than one category would include the initial letter of every category and an assigned reference number starting from one for each combination of letters (e.g., C/O-1, C/O-2, E/N-1, E/N-2, and so on).

Based on the list in Table 2, the application of MPs in IC can be realised. All the information is useful for different CE processes. However, its significance would vary from one piece of information to another depending on the contribution for circularity actions. As discussed earlier in Section 4.1, different uses of MPs are achieved based on the information available at different stages of the lifecycle. For example, the information available at the planning and procurement stage of the IC lifecycle mostly provided by the manufacturers would help distinguish the environmental performance and select the materials for construction. Similarly, when the manufacturing is in progress, various pieces of information that were supplied by the manufacturers would have to be followed up on and ascertained. Furthermore, the environmental performance information of the materials needs to be tracked and ascertained throughout the asset delivery phase. At the end of construction, during handover, the final information of the materials embedded in the building is obtained, which is useful for the further operational and end-of-life stages. Such as-built information is necessary for material circularity, i.e., upcycling or downcycling the use of the material at the end of the lifecycle. It can be noticed above, in Table 2, that some information is generated and recorded only once, while some is updated as the lifecycle progresses (it can be observed with repeated identifier codes), thus it can be labelled as ‘static’ and ‘dynamic’ types of information, respectively. Further analysis of the information to study the types and its contribution or significance for circularity would lead to determining the guidelines for its management throughout the lifecycle. A further step is to identify the actors that are the key stakeholders for information management. A credible source for each piece of information needs to be defined, which in other words also means defining the role each stakeholder would have in information management. The need for the classification of information, mentioned in the previous section, is also a key requirement to determine the actions required for managing each piece of information. Additionally, digital technologies that would help realise the management of information are to be studied for developing a working information management system.

7. Conclusions

Implementing material passports (MPs) for managing information about materials, to make them reliable for the next user and to ease their handover, was established in this study. In addition, the adoption of industrialised construction (IC) would allow us to achieve resource-efficient methods in production and operation and would further assist in the development and management of MPs because of their robust information management system. These led to the conclusion that the adoption of IC for the construction of any new asset and the provisioning for MPs of such an asset is the way to create a circular economy (CE) in construction. This would enhance CE implementation in construction to the fullest form possible as CE actions can be taken right from the design stage and material reuse can be facilitated through genuine material information. Once that was established, the study progresses with listing out exact information for MPs. As the construction type to be adopted is IC, the information list was adapted and shortlisted under IC lifecycle processes. Thus, a comprehensive list, with information and the respective lifecycle process it was created from, was developed. The final list developed is an elaboration of the pattern of information flow and the list of information types for different lifecycle stages discussed in Section 4.2. Knowledge about the type of information to be particularly managed for each stage enables the application of MPs in IC.

There are limitations to a literature review and the development of a required MP information management system can be furthered through research previously discussed at end of Section 6, such as study for the classification of information based on materials’ nature and significance, study for the application of digital technologies for developing and managing MPs, study to define the stakeholders involved and their roles at different stages in the lifecycle, and the exact sources of material information to be incorporated into MPs. These studies would include further literature review, industry review, and experts’ input. By employing the managerial and technological know-how thus established through further studies, a functioning information management system for MPs can be developed. As this study focuses on IC application for a CE, the stakeholders and managerial actions that are relevant in industrialised construction should be further focused to extend the arguments and intentions put forward by this study. Eventually, the developed MP framework would be the guide to develop different MP systems customised to suit their assets. This study is the initial and vital step towards achieving material circularity thorough MPs and (in) IC. Furthermore, the relevant knowledge about MPs and IC aspects gained from this study would also enable learning and working towards achieving CE in the construction industry.