Closing the loop in building services: A systematic review of circular economy applications

Abstract

The substantial environmental impact of buildings has garnered significant attention. However, sustainability efforts often prioritise structural and envelope materials, overlooking building services - systems for ensuring occupants’ safety and comfort. Given their complexity, rapid technological advancements, and substantial costs, these components necessitate a circular economy approach to optimise resource utilisation. This study conducts a systematic literature review to assess the current state of circular economy implementation in building services, identifying barriers, opportunities, key influencers, and potential strategies. Findings indicate that applying circular economy principles within building services remains nascent. Barriers encompass technical, economic, legislative, and organisational challenges. Conversely, numerous opportunities exist, alongside six key influential stakeholders. The analysis enabled the development of a framework to integrate existing principles and building blocks with identified essential strategies for advancing circular building services. The integrated strategies include design, business models, policy, product information, warranties, life cycle costing, digital technology, education, collaboration, and transparency. This study recognises various research gaps and highlights the need for further exploration to realise the full potential of circular economy in building services. Ultimately, a shift in mindset, coupled with new skills and holistic approaches, is required to drive progress in this domain.

Practical application

The application of circular economy in building services is still nascent, representing a missing piece for advancing sustainable construction. This paper examines the existing knowledge in this domain to identify barriers, opportunities, and key influencers. The strategies identified enabled a framework for advancing circular building services. The study is vital for engineers, designers, researchers, policy makers, and all other stakeholders to advance circularity in the building services sector.

Keywords

Circular economy (CE)building services mechanical electrical and plumbing (MEP)heating ventilation and air conditioning (HVAC)systematic literature review (SLR)

Introduction

Addressing environmental challenges remains a paramount priority across all industries. Nonetheless, the built environment continues to pose significant sustainability concerns. This sector is characterised by high energy and resource consumption and substantial waste generation.^1–3 Also, the industry’s greenhouse gas emissions have shown a concerning upward trend, accounting for an estimated 37% of global CO₂ emissions.⁴ Despite undeniable economic and social benefits, a growing body of research highlights the detrimental environmental impacts of the built environment.^2,5,6 These impacts encompass the entire life cycle of construction projects, often called “cradle-to-grave,” including resource extraction, manufacturing, transportation, construction and end-of-life disposal.

The impact of buildings and their components on the environment can vary. The Building “shearing layers” concept, conceived by Frank Duffy and later popularised by Stewart Brand, offers profound perspectives on the dynamic nature of building structures and their evolution with time. Various layers, including site, structure, skin, services, space plan, and stuff, have distinct lifespans and impacts on sustainability and building performance.⁷ These layers can then be categorised into fast- or slow-changing based on their frequency of replacement or repair. The building services layer, referred to by Brand as “the working guts”, wears out and changes frequently and can impact the lifespan and overall performance of a building.

The Chartered Institution of Building Services Engineers (CIBSE)⁸ and The Royal Institution of Chartered Surveyors (RICS)⁹ categorised building services into thirteen categories (sanitary, disposal, water, ventilation, space heating, air conditioning, and others). However, The American Society of Heating, Refrigerating and Air-Conditioning Engineers¹⁰ outlined HVAC across five applications (comfort, industrial, energy-related, building operations and management, and general applications). The most common categorisation includes Mechanical, Electrical, and Plumbing (MEP) and Heating, Ventilation, and Air Conditioning (HVAC). Despite their vital functions, building services are responsible for a high proportion of energy consumption and carbon emissions, leading to significant environmental impacts.^11,12 In the UK, for example, the built environment represents 42% of total CO₂ emissions, of which 16% are from operational energy consumption by building services.¹³ However, various assessments to advance sustainability in the construction industry often neglect building services and focus on building structure and envelope.^14,15

Building services and their components are usually complex, sophisticated, cost-intensive, and encompass numerous materials.^15–17 CIBSE¹⁸ outlined the commonly used primary raw materials, such as metals (copper, steel and aluminium), plastics (polyvinyl chloride, acrylonitrile butadiene styrene, and polyethene), rubber (rubber, silicone, neoprene, and ethylene propylene diene monomer), adhesives and sealants (epoxide resin, silicones, and acrylics), and insulation (fibreglass, mineral wool, and cellulose).

Building services also require frequent maintenance, repair, and replacement, resulting in higher embodied carbon.^19–22 In new construction, MEP systems can represent 2 to 27% of embodied carbon, reaching up to 75% in retrofit and continuously increasing over the system’s lifespan.^18,23 While the building structure and envelope often have a lifespan of 50 to 100 years, building services have a lifespan of 15 to 25 years, and even less, most times.^24,25 Also, building services represent 30 to 60% of capital cost, sometimes reaching 75% in medical uses and up to 90% of operational costs of buildings.^16,25

In-depth studies on building services’ embodied carbon and environmental impact have outlined the significant adverse effects and recommended a paradigm shift towards a circular economy.^26–28 A Circular Economy (CE) is a regenerative or restorative business concept that replaces the “end-of-life” theory, advances renewable energy, eradicates toxic chemicals hindering reuse, and aims to eliminate waste by intentionally and carefully designing resources, goods, systems, and economic models.²⁹

The evolution of CE is founded on various archaic concepts: industrial ecology and symbiosis, cradle-to-cradle, Commoner’s four laws of ecology, performance economy, biomimicry, regenerative design, natural capitalism, and the Slowing, Closing and Narrowing Resource Loops.^1,30 Various frameworks to advance the circular use of resources and waste reduction are emerging, like the four distinct resource loops: narrow, slow, close, and regenerate.^1,31,32 The 4 Rs principles of “reuse”, “reduce”, “recycle”, and “recover” have also emerged and remain dominant across various sectors.³³ Though noting the use of up to 38 Rs, Reike et al.³⁴ united diverging perspectives and recommended 10 Rs. Adopting CE implies that resources are preserved and retained in a continuous usage loop, as opposed to the traditional one-off consumption and disposal in the linear economy.³⁵ Often, the smaller the loop, the less energy and resources are required.

The CE model proffers a solution within the construction sector by promoting recycling and reuse of resources, waste reduction, and energy efficiency.³⁶ Existing approaches aligned to the application of CE in construction include design for disassembly, passive design, environmental product declarations, recyclability and reusability, urban mining, energy efficiency and zero carbon buildings, life cycle analysis, material passport, buildings as material banks, products-as-a-service, local resources use, waste reduction, and deconstruction.^2,6,37–39 Spanning through the various stages of the building lifespan, these approaches are pivotal to a sustainable and resource-efficient construction industry. McConahey⁴⁰ emphasised that findings on the global warming potentials of building services must prompt building designers to explore CE principles critically.

While the real-world deployment of circular solutions in building services is minimal, some pioneers have set the pace in their projects and businesses. Grundfos, an HVAC pump manufacturer based in Denmark, has focused on eliminating landfill waste, streamlining its production process, and reducing energy usage and material consumption.²¹ They implemented a take-back programme on pump circulators to remanufacture and recycle components and reduce waste across seven EU countries.^23,41 In 2022, Grundfos reduced total landfill waste by 32% since its baseline year and collected 64,288 kg of pump circulators.⁴¹

Another pioneer of CE solutions in building services is L∞P by Daikin, launched in 2019 to recover, reclaim, and reuse refrigerants.⁴² Reitmeier HVAC Services in the US has also recovered air filters from its clients since 2016 and collaborates with an energy-from-waste (EfW) facility to produce energy from these air filter wastes.²³ Circular business models have also been explored for building services, such as Philips “light as a service” and Kaer “cooling as a service”.^13,21 In the lighting industry, the shift from conventionally lamped luminaires to energy-efficient light-emitting diode (LED) luminaires resulted in an unmaintainable product with a shorter life span and a complex supply chain.⁴³ Recognising these unintended consequences, CIBSE⁴³ developed technical guidance for all stakeholders to advance circularity in the lighting industry.

Though minimal, some research outputs have considered CE in building services.^21,23,27,44 Most related research outputs on CE and building services have focused on life cycle assessments,^{14,26,45–47} embodied carbon,^{15,18,19,47–49} material flow analysis,⁵⁰ and environmental assessments.⁵¹ Rabie and Sjöholm²⁸ examined the adaptive reuse of HVAC components within an office-building case study in Sweden. Stiglmair and Jurkait⁵² also outlined guidance for engineers to implement cradle-to-cradle in building services design.

However, the application of CE in building services is still nascent and has experienced very little research.^23,27,28 The advancement of CE in building services is constrained by knowledge gaps and the multifaceted supply chain, which mostly requires products and sub-components from third-party suppliers.^21,27 Robust market insights and circular options to replace existing HVAC systems are also not widely available, and stakeholders hesitate to incur the initial capital required to explore new circular solutions.²³ Essentially, a shift in the supply chain and business model of building services is necessary, and building services is a “golden spot” for implementing CE principles.²¹

Despite numerous literature reviews on CE in construction,⁵³ no review studies broadly examine the application of CE in building services and components. A critical review by Seuntjens et al.⁵⁴ focused on only ventilations in adaptable buildings, excluding many other building services components. Therefore, this paper aims to fill the knowledge gap by examining current knowledge on the application of circular economy to close the resource loop in building services. The paper systematically reviews existing literature to identify the current applications of CE in building services, and identify recurrent barriers and opportunities, key influencers, and map out recurrent strategies for improved application. This review is vital for influencing improved research and industry efforts in this subject area, ultimately advancing sustainable buildings and construction. The paper is organised in five sections. The next section outlines the methodology. This is followed by the analysis of the systematic review which is in two parts; descriptive and thematic. There then follows a discussion that presents a framework and identifies the gap in the research. The paper draws to a close with the conclusions.

Methodology

The study conducted a systematic literature review (SLR) of research outputs in existing databases, as adopted in numerous related research outputs.^55,56 SLR is useful in developing frameworks for future research by analysing and mapping existing knowledge from a large body of literature.⁵⁷ The preferred reporting items for systematic reviews and meta-analyses (PRISMA 2020) guideline was utilised to search, evaluate and extract the literature metadata for the SLR.⁵⁸ As an evidenced-based framework, this guideline has also been adopted in numerous SLRs related to circular economy in the building and construction sector.^59,60

Web of Science (WoS) and Scopus were adopted as the primary databases for extracting the existing scientific outputs. Using multiple databases ensures an extensive coverage of bibliometric data, and these two represent the most influential digital databases for scientific research globally.² Considering that many relevant outputs on circularity in building services exist outside academic and scientific databases, the SLR includes relevant published outputs from external sources. This approach is regarded as best practice² and will “supplement results retrieved from a citation database with additional publications to reach the desired level of completeness for the study at hand”^{61, p.66}.

The search syntax deployed for extracting the existing scientific outputs includes a combination of keywords related to the research area and adopting various Boolean operators as defined below.

1. Circular Economy AND “Building Services”

2. (Circular* OR Regenerat*) AND (“Building Services” OR “Mechanical Electrical Plumbing” OR “Heating Ventilation”)

3. (Reuse OR Recycle) AND (“Building Services” OR “Mechanical Electrical Plumbing” OR “Heating Ventilation”)

A wild card (*) is also attached to some words to ensure the inclusion of their various forms and plurals, and quotation marks and brackets were used to ensure an exact match. The keyword for HVAC adopted only “heating ventilation” based on the notion that the term usage always commences with these two words. The search in both Scopus and WoS was set to be performed within the article titles, abstract and keywords. Even though the advocacy of CE received tremendous attention during the last decade, no year range was applied to the search since CE is rooted in various archaic concepts. The literature search was inclusive, without restrictions on article types, subject areas, or countries of origin. However, only literature published in English language was considered for ease of review and analysis.

A total of 301 publications were retrieved from both databases in June 2024, as shown in the PRISMA flow diagram in Figure 1. Overlapping duplicates (86) from both databases were removed, resulting in 215 publications. 23 publications were also considered for screening from external sources. Before screening using various inclusion and exclusion criteria, this bibliometric data was collated in EndNote and exported to VOSviewer.

Figure 1.

PRISMA flow diagram of the bibliometric data retrieval and assessment.

The network visualisation in Figure 2 displays terms that occur in titles, abstracts and keywords of the bibliometric data selected based on a 60% relevance score of terms with a minimum of five occurrences. The proximity of terms depicts the occurrence relationship, while the size variation represents the frequency of occurrence. Four notable clusters are observed, with “building service” representing the link between all the clusters. While there are many terminologies, only the red cluster visually represents the terms directly relevant to the research focus, indicating that only a few publications in the bibliometric data would be appropriate to the research.

Figure 2.

Network visualization of terminology occurrences in bibliometric data by VOSviewer.

Various inclusion and exclusion criteria were then utilised across three screening stages to determine the publication to be included in the SLR. A first-stage manual screening was conducted on the titles and abstracts of all the publications to review the alignment of the publication with the research focus. Only 38 publications aligned with the research focus, as earlier projected by the VOSviewer mapping technique. Many of the publications initially retrieved from the databases used the search syntax in other contexts, such as “circular” representing “round” and building services used in the context of “service life of buildings”. Some other publications, though relating to buildings’ HVAC, focused on regenerated energy, recycled water and reusable fluorinated gases rather than the building services components.

A second stage screening of the title, abstract and conclusions was conducted to decide on publications to be retrieved. The screening ensured that the publication had a strong connection or recommendations regarding building services and circular economy. 17 publications were excluded. A third-stage screening retrieved the full text of all the 21 articles included. A quick scan-through was done by searching for “building services”, “mechanical, electrical, and plumbing”, “MEP”, “heating, ventilation”, or “HVAC” to understand the exact use cases of these search syntax within the full article of the publications. Two publications with no full text available as of the review were excluded. Eight publications did not fulfil the inclusion criteria, resulting in only 11 publications in the SLR.

At stage 3, 14 other relevant publications on circularity in building services previously identified from websites, journals, and universities were considered. Snowballing was also conducted to identify relevant articles that did not appear in the database search by reviewing the references and citations of all included. Nine publications were identified for screening via references and citations. Observation revealed that some of these articles were initially omitted from the database syntax search because of the word choice, such as “technical services” and “comfort systems”. A total of 23 publications were therefore considered from external sources for screening. The full text of these publications was retrieved and reviewed to examine relevance to the research focus. Five articles did not fulfil the inclusion criteria and were excluded. Some excluded publications outlined the technicalities of how new building services components function in adaptable buildings. After in-depth screening, only 18 articles from external sources were included in the SLR.

The retrieval and screening of all the bibliometric data in three stages for the systematic literature review is outlined in the PRISMA flow diagram in Figure 1. While the study is believed to represent the existing body of knowledge on the focus area, the research was conducted within the limitation of the availability of relevant literature, scientific databases and sources, language restrictions, and time constraints.

Results

The analysis of the SLR is presented in two categories. The descriptive analysis outlines the results identified from the bibliometric data of all the publications included in the SLR. This analysis is essential for contextualising the systematic review procedure and the thematic outcomes.⁶² The thematic analysis outlines various research axes based on patterns and parallels.

Descriptive analysis

The 29 publications considered in the SLR were published between 1997 and 2024, see Figure 3. The five publications before 2000 represent a 2-year research project on reuse in building services by the same group of researchers at Heriot-Watt University, UK. The study, themed “Designing for short life”, was funded by the UK Engineering and Physical Sciences Research Council (EPSRC) and sought to determine the technical feasibility and economic viability of reusing building services components in the healthcare sector.⁶³ A guide for recycling building services was published in 2003 by the UK Building Services Research and Information Association (BSRIA).

Figure 3.

Timeline of publications included in the systematic literature review.

There is a gap in publications from 2003 until 2012. The article in 2012 outlines design guidance for reusing construction materials, with a chapter focused on mechanical and electrical services. Afterwards, CIBSE and ASHRAE published relevant outputs in 2014 and 2015, respectively. Exploratory research on circular economy in building services did not advance until 2018 when researchers at University College London and Arup examined two case studies. A consistent upward trend is observed afterwards, with 2022 being the highest point for research in this domain so far. Considering that this SLR was conducted in the first half of 2024, further research outputs may be published before the end of the year, with no certainty of attaining the peak point observed in 2022.

The literature included in the SLR spread across various publication types, as reflected in Figure 4. Journal articles (31%) ranked highest, followed by conference proceedings (28%) and books (21%). Technical reports (10%) and Thesis (10%) had the same number of articles. Most of the publications in the SLR were case studies (38%) of real-life projects and buildings where researchers evaluated the circularity of building services components. Guidelines (24%) and principles for designers and building services engineers to implement circular economy in building services also ranked high. Others include frameworks (7%), opinions (7%), surveys (3%), interviews (3%), book review (3%) and literature review (3%).

Figure 4.

Distribution of outline and type in the SLR.

To understand the geographical spread, the country of each publication is also extracted from the metadata. The country of research is adopted as the location for case study research. For others, the country of the affiliated institution for the first researcher was adopted. The regional concentration of research within Europe is vividly observed, with 86.21% of research emanating from this region. A few studies from Asiatic countries were also included, representing 10.34%. Unexpectedly, only one publication was identified from America (3.45%), and no publications were observed from other geographical regions.

The investigation of the relationship among various bibliometric data in VOSviewer did not present any significant outcomes. A word cloud of the keywords was generated as an alternative, as shown in Figure 5, to visualise the thematic focus of the literature included in the SLR. “Circular economy” and “reuse” represent the most frequent words, followed by “building services”. Other notable words include “lifecycle”, “business”, “design”, “energy” and “assessment”.

Figure 5.

Word cloud of keywords included in the systematic literature review.

Thematic analysis

The thematic analysis of the literature identified four key themes. The first theme identified the recurrent limitations and barriers identified by the various publications. Based on similarities and affinity, the limitations and barriers are categorised into four axes: technical, economic, legislative, and organisational. 79% of the literature mentioned technical barriers, 72% included economic barriers, 55% outlined legislative barriers, and 59% mentioned organisational barriers.

The second theme examines the opportunities for implementing circular building services. 76% of the literature identified the opportunities and benefits of implementing CE principles within the building services sector. The third theme considers the role of various stakeholders across the building services supply chain. The six major key influencers are noted in the literature. Their frequency of occurrence includes clients (31%), manufacturers (45%), designers – architects and planners (55%), MEP engineers (28%), developers and contractors (45%), and policymakers (14%).

The fourth theme outlines the various strategies outlined across the literature to advance/enable CE applications in building services. These strategies are categorised under nine axes based on similarities. These include design (76%), business model (55%), policy (31%), product information (31%), warranties (24%), life cycle costing (17%), digital technology (24%), education (17%), and collaboration and transparency (17%). Table 1 outlines the exhaustive list of all the identified publications for the SLR and their corresponding opinions on the four key themes from the findings.

Table 1.

Summary of findings from publications included in the systematic literature review.

Author	Type*	Country	Outline	Barriers	Opportunities	Key influencer	Strategies
Webb et al.⁶⁴	JA	UK	Article	α γ	√	θ	ν π τ
Webb et al.⁶³	CP	UK	Article	α β	√	λ	ν π τ
Thomson et al.⁶⁵	JA	UK	Survey	α β γ ε	√	ζ κ λ	τ
Thomson et al.⁶⁶	CP	UK	Article	α β γ ε	√	ζ κ λ	π
Webb et al.⁶⁷	JA	UK	Framework	α			τ φ
Olnhoff and Martin⁶⁸	B	UK	Guideline	β γ ε	√	η μ	π ρ
Addis⁶⁹	B	UK	Guideline	α β γ ε	√	η θ λ μ	ν σ τ
CIBSE²²	B	UK	Guideline	α β γ	√	η θ	ν π σ φ
Afify⁷⁰	JA	USA	Opinion	α β		ζ θ	ν
Croxford et al.²¹	TR	UK	Case study	α β γ ε	√	η θ	ν π ρ φ ψ
Ciugudeanu et al.⁷¹	JA	Romania	Case study	α ε			ν
Jurkait and Stiglmair⁷²	CP	Germany	Review	β ε	√	ζ η θ κ λ	χ
Stiglmair and Jurkait⁵²	B	Germany	Guideline	β ε	√	ζ η θ κ	ν π σ
CIBSE¹³	B	UK	Guideline	α β	√	η θ λ	ν π ρ ω χ ψ
UKGBC⁷³	TR	UK	Guideline	γ	√	ζ η θ λ	ν π ω
CIBSE⁴³	B	UK	Guideline	α γ ε	√	ζ η θ	ν π ρ σ τ φ χ
Oosting²⁷	TR	Netherlands	Opinion	α β γ ε	√	η	ν π σ
Chai et al.⁷⁴	JA	China	Framework	α γ		λ	ν
Loreau et al.⁷⁵	CP	Greece	Case study	α	√	κ
Loreau et al.⁵⁰	CP	Belgium	Case study	α β ε	√		π σ
Seuntjens et al.⁵⁴	JA	Belgium	Review	β		θ κ	ν π ω
Theißen et al.¹⁴	CP	Netherlands	Case study	α γ ε	√	θ μ	ν σ ω φ
Lundgren et al.⁷⁶	JA	Sweden	Case study	α β ε	√	θ λ	ν π ψ
Mohamad et al.⁷⁷	CP	Malaysia	Case study	α β γ ε		λ	ν ρ
Patil²³	T	Netherlands	Interview	α β γ ε	√	ζ η θ κ λ	ν π ρ σ ω φ ψ
Zainal Abidin⁷⁸	CP	Malaysia	Case study	β			ν
Kaarmila⁷⁹	T	Finland	Case study	α β γ ε	√	η θ	ν ρ φ χ
Pichlmeier and Lindner⁴⁴	JA	Germany	Case study	α β	√	θ λ	ν ρ σ χ
Rabie and Sjöholm²⁸	T	Sweden	Case study	α β γ ε	√	ζ η κ λ μ	ν π ρ τ ψ

*JA: journal article; B: book; CP: conference paper; TR: technical report; T: thesis; α: technical; β: economic; γ: legislative; ε: organisational; ζ: clients; η: manufacturers; θ: designers; κ: MEP engineers; λ: contractors; μ: policymakers; ν: design; π: business model; ρ: policy; σ: product information; τ: warranties; ω: life cycle costing; φ: digital technology; χ: education; ψ: collaboration.

Discussion

The discussion of the SLR result is structured into three segments. The discussion of the descriptive analysis is presented, followed by the discussion of the various themes identified in the literature. In conclusion, the research gaps identified from the literature are also outlined.

Descriptive discussion

The timeline of publications in the SLR represents a gradual growth in the research focus, commencing in 1997 with research primarily focused on reuse and recycling. The gap from 2003 until 2012 suggests a vacuum in research and industry efforts on circularity until the launch of the Ellen MacArthur Foundation in 2010 and the subsequent diverse efforts by other organisations to advance CE. The increase in research, which peaked in 2022, suggests that advancing circularity in building services has attracted attention in recent years. However, compared to the volume of research on the broad theme of circular economy in construction, this research focus is still in the nascent stages.

Most of the publications in the SLR were case studies of real-life projects and buildings in which researchers evaluated the circularity of building services components. The findings from these exploratory researches are then published in journals and presented at conferences. This outcome depicts this research area’s highly pragmatic nature and the growing interest in identifying real-life solutions to address the problem. The high rank of guidelines and principles for building services designers and engineers demonstrates that practical knowledge of approaches and processes is still lacking.

The evident large concentration of research within European countries can be attributed to significant legislation mandating CE principles within the region. This concentration was also observed by Munaro et al.⁶² and Benachio et al.⁵⁵ Regulations, like the EU Waste Electrical and Electronic Equipment (WEEE) Directive and Circular Economy Action Plan (CEAP), would have influenced the dominant research within the region.^23,27,43 Similar regulations also exist in the Asiatic region, from which a small amount of the literature emanates.

The keywords in the word cloud accurately represent the intended research focus for the literature compared to the initial network visualisation of all the exported bibliometric data. This indicates that the inclusion and exclusion criteria used across the three screening stages effectively eliminated irrelevant literature. The critical terms observed also suggest that “reuse” is the most frequent approach for “circular economy” applications in building services. The use of “life cycle” and “assessments” is vital, and “design” represents the most viable stage for implementing CE. “Business” models are also essential, and “energy” efficiency must be integrated into circularity. Ultimately, the broad approaches for advancing CE in construction also apply to building services, and focused research is still in its infancy.

Thematic discussion

The thematic discussion examines the four key themes identified in the literature, as represented in Figure 6. Four categories of barriers to applying CE in building services are outlined. The opportunities and benefits of implementing CE in building services were also established. Various stakeholders in the building services supply chain and their influence in promoting CE are considered. A framework is then developed, integrating existing principles and building blocks with identified strategies for advancing the application of CE in building services.

Figure 6.

Outline of the thematic discussion of the SLR.

Barriers

Across the construction sector, the barriers to implementing a circular economy (CE) have been widely researched. While many of these also impact building services, the sophisticated and cost-intensive, low-life span nature of building services supply-chain poses other barriers. These barriers can be broadly categorised into technical, economic, legislative, and organisational challenges, as also categorised by Patil²³ after interviewing industry experts and stakeholders.

Technical barriers

A comprehensive literature analysis reveals several technical challenges impeding the successful implementation of CE principles within the building services sector. Webb et al.,⁶³ Thomson et al.,⁶⁵ Rabie and Sjöholm,²⁸ and Patil²³ highlighted the rigorous maintenance and testing protocols associated with ensuring that reused components provide a guarantee of long-term performance. Reconditioned elements often fall short of the stringent operational demands imposed on new systems, as these components may suffer from degradation, higher energy consumption, and reduced efficiency.^23,66,75 Technological advancements have also posed challenges to the reuse of building components.⁵⁰ Thomson et al.⁶⁶ and Chai et al.⁷⁴ emphasise the detrimental impact of technological obsolescence on the viability of reused building services components. Croxford et al.²¹ and CIBSE¹³ also confirmed that building services’ fast obsolescence and well-known performance gaps hinder CE applications.

The lack of standardised methods for assessing reuse potential further hinders progress in this area.⁷⁵ Moreover, the complexity of building systems, particularly HVAC, exacerbates these issues. The retrofitting process of building services is complex, time-consuming, and requires experts.⁷¹ Oversized HVAC systems, common in renovations, present additional challenges due to inefficiencies and maintenance requirements.⁷⁰ Webb et al.⁶⁷ also note the importance of “packaging” reusable components to possess attributes such as adequate maintainability and ease of isolation. This suggests that the practicality of reusing existing components is limited without significant technical modifications. The design approach of embedding building services into the building structure and façade poses a considerable barrier, leading to loss of materials and embodied energy.^21,44 Mohamad et al.⁷⁷ emphasised that adaptive reuse of building services components in heritage buildings often alters the structural elements, impacting the historic fabric. In the attempt to adopt circularity, building services components must also not compromise on energy efficiency,⁶⁹ such as the increased energy consumption experienced in the case study by Lundgren et al.⁷⁶

The circularity of building services lags behind that of the construction sector.²⁷ Despite the widespread use of life cycle assessments to advance sustainable construction, building services components are often omitted due to the complexity of manually calculating the embodied carbon.²⁸ Another barrier is the lack of granular information and comprehensive data about building services materials and components.⁴⁴ The simplified representation of building service components in certification systems and digital BIM models always results in insufficient evaluations.^14,28,44 Factors such as limited knowledge about the component composition sector,²⁷ the need for structural reinforcement and system redesign,⁷⁴ and the challenges associated with recycling certain materials⁷⁹ compound the obstacles to achieving a truly circular economy in building services.

Economic barriers

Economic considerations significantly impede the widespread adoption of CE principles within the building services sector. A recurring theme in the literature is the economic viability of component reuse. Webb et al.,⁶³ Olnhoff and Martin,⁶⁸ and Thomson et al.⁶⁵ highlight the substantial costs of segregating, reconditioning, transporting, and storing used components. The initial capital expenditure required to establish CE systems is often perceived as a deterrent, with traditional linear approaches appearing more cost-effective in the short term.⁷² While Webb et al.⁶³ identify high-value components as potential candidates for economically viable reuse, drawing comparisons to other industries like automobiles, Olnhoff and Martin⁶⁸ caution that even these components, such as compressors and pumps, may not always justify the upfront costs of reconditioning and testing. To overcome these challenges, Rabie and Sjöholm²⁸ emphasise that the cost of reuse must be lower than that of acquiring new components.

The absence of a mature secondary market for used building services components exacerbates the economic barriers. Loreau et al.⁷⁵ and Croxford et al.²¹ identify this as a critical issue. The relatively low quantities generated by building services compared to other materials in construction and demolition waste^27,68 further limits market development. Patil²³ characterises the current market as predominantly linear, with limited circular options and, consequently, high costs for implementing circular approaches. The challenges of identifying reliable sources of reusable components⁶⁵ and the low market value of recovered materials⁶⁹ further discourage reuse. The economic impacts of the logistics required for reusing building services components must also be evaluated.²²

The economic viability of reused components is also impacted by factors such as short lifespan, high maintenance costs, and difficulties ensuring durability.^21,69 Thomson et al.⁶⁶ emphasise the importance of guarantees in mitigating client economic risks. Interestingly, financial pressures can sometimes drive the adoption of reuse, as Afify⁷⁰ noted that budget constraints can influence clients to opt for reused building services components despite potential inefficiencies and increased energy consumption.

There is also no clear understanding of the financial incentive and circular business models.^21,68 While the potential for cost savings through increased resource efficiency is acknowledged,²² Jurkait and Stiglmair⁷² caution that implementing circular approaches in building services often involves higher initial costs and necessitates new economic models.^54,76 Broadly, the perception of CE initiatives as risky investments further hinders adoption.^13,79

Legislative barriers

The absence of comprehensive and supportive legislation poses significant challenges to reusing building services components. CIBSE²² and Thomson et al.⁶⁵ advocate for clear guidelines and standards to facilitate component reuse. While advancements such as the WEEE Directive represent progress, more robust regulatory frameworks are essential.⁴³

Existing building codes and regulations, often tailored to new components, impose stringent performance and safety standards that hinder the reuse of older components.^66,69,74 Targets related to energy efficiency, thermal comfort, and energy use often constrain reuse.^23,28 For instance, the evolving legislative requirements of increased energy efficiency for boilers limit the reuse of older systems.⁶⁹ However, safety must remain paramount for CE products and services.⁴³

Rabie and Sjöholm²⁸ and Webb et al.⁶⁴ highlight the absence of regulatory support for performance-based specifications, which could otherwise foster an environment conducive to component reuse. The prevailing regulatory rigidity often compels stakeholders to select new components to ensure compliance, discouraging reuse. The lack of standardised environmental auditing and clear governmental policy guidance exacerbates these issues.^43,65 Moreover, contradictory legislation and complex waste regulations hinder effective recycling strategies.⁶⁸

Current laws inadequately support CE business models and assessments,^14,79 necessitating mandatory regulations that enable increased adoption.²³ While UKGBC⁷³ emphasises the importance of industry-led initiatives and knowledge sharing, it also acknowledges the need for more robust legislative frameworks to promote resource efficiency and net zero-carbon buildings. Oosting²⁷ further emphasises the need to integrate material scarcity and circularity principles into legislation to support CE goals.

Organisational barriers

Transitioning to a circular economy necessitates significant organisational culture and behaviour shifts within the building services industry. The industry’s fragmented nature and prevailing linear economy mindset hinder the adoption of CE principles.^21,23 Overcoming entrenched practices and fostering a circular mindset is essential.^23,79

Jurkait and Stiglmair⁷² highlighted a knowledge gap regarding the benefits and methods of reuse, emphasising the importance of education and awareness within the industry. Clients often lack the necessary expertise and rely on consultants²³ despite a scarcity of adequately skilled and experienced personnel.⁷⁷ The limited sustainability knowledge within the industry⁴³ could also lead to clients and professionals imposing restrictions on implementing CE initiatives.⁶⁶

Olnhoff and Martin⁶⁸ identify a general apathy towards environmental issues within the construction industry, which extends to a reluctance to adopt sustainable practices, including building services component reuse. The minor representation of HVAC systems in Life Cycle Assessments (LCA) and circularity assessments^14,28 highlights a broader disregard for the circularity of building services. The implementation of circular business models is also slow, and there is a need for comprehensive lifecycle assessments to understand the environmental and economic impacts of these models better.⁷⁶ The loss of historical component data during transfer leads to uncertainty about their performance⁶⁵ and further complicates reuse efforts.

The fragmented nature of the building services industry, characterised by separate procurement processes for various works and services, impedes coordinated CE initiatives.^21,27 This fragmentation impedes coordinated efforts to improve circularity in building services, and achieving circularity by all stakeholders across the project lifecycle remains challenging.^52,69 To successfully implement circular principles, the entire project team, from investors to engineers, must be committed to the concept.⁷² Thomson et al.⁶⁶ also pointed out the nonexistence of a dedicated sector focused on reconditioning and reusing building services components. Developing supply chains to support the reuse of these components requires focused efforts from decision-makers.⁵⁰

Opportunities

Adopting CE principles within the building services sector benefits various industry stakeholders and the environment. A core objective of circularity is to enhance resource efficiency and reduce reliance on virgin materials.¹³ Implementing circular practices makes construction more sustainable and resource-efficient.^50,69,79 This approach minimises waste,⁶⁸ reduces the demand for new materials,^21,44,75 and lowers carbon emissions.^23,43,75

Beyond environmental advantages, circular building services offer economic benefits. Adoption circularity unlocks the opportunity to reduce capital costs and price volatility risks.^22,63 Rabie and Sjöholm²⁸ highlighted that adopting circularity benefits clients and building owners. However, this depends on the approach, volume of material, availability and building type.^23,28,72 To maximise these benefits, careful assessment of component physical reliability and technological performance is essential.^65,75 Ultimately, the accurate estimation of financial returns from circular initiatives is crucial.⁶⁹ Additionally, implementing circular approaches can improve project risk management, particularly regarding long-term resource availability and pricing.²² Patil²³ reiterated that future material scarcity and price volatility would propel the industry to adopt circular initiatives.

The shift to circularity creates opportunities for new business models and market development. A market for pre-used building services systems is required,⁷⁵ along with a remanufacturing and reconditioning industrial sector.^64,66 The development of diverse circular business models, such as Product-as-a-Service (PaaS) and leasing, offers economic opportunities^43,73 and can mitigate disruptions faced by traditional manufacturers when circularity is adopted.²⁸

Building Information Modelling (BIM) and 3D printing present opportunities to streamline operations and improve recyclability.²² Leveraging digital technologies, like 3D printing and robotics, enhances the manufacturing and installation of building services components.²¹ BIM and digital tools also enable effective information management and storage, which ensures better lifecycle management of building services components by facility managers.^21,79

Key influencers

The successful transition to a circular economy within the building services sector necessitates a collaborative effort involving multiple stakeholders across the value chain. All authors refer to various roles as the key influence, indicating that every stakeholder has a critical responsibility. For Olnhoff and Martin,⁶⁸ the advancement of circular building services is hinged on the whole industry adopting good practices. Jurkait and Stiglmair⁷² also highlight that the entire project team is pivotal, including even investors and close collaboration is required.^13,73 While all parties bear responsibility, specific roles are particularly influential in driving this shift.

Clients and building owners are pivotal in shaping the demand for sustainable and circular practices, ultimately improving their investment returns and emission targets.²³ A client-led demand and commitment to incorporating sustainability goals into projects is essential.^43,70 Active involvement in the design process allows clients to identify and implement practical circular applications.^52,73

Manufacturers are critical in promoting circularity through product design, resource efficiency, legislative compliance, and reduced carbon emissions.^22,69,72 Collaboration between manufacturers and designers is also vital, particularly to innovate in product design.^13,23,43,52 The role of manufacturers in ensuring product sustainability from cradle to cradle is crucial for the overall success of circular initiatives.^27,43

Design teams also drive circularity through the design process.^{21,22,54,69,70} Design is the most critical stage in promoting and adopting circularity.^23,79 Clients rely on the knowledge and expertise of design teams to proffer solutions and decisions that advance circularity.²³ Designers must also evaluate the reusability of materials and components, ensuring no compromise in building performance, maintenance, or safety.^69,70 Webb et al.⁶⁴ highlight designers’ importance in creating a procurement environment that encourages component reuse. BIM can enhance the design process and support circularity.²²

MEP engineers are vital in determining the feasibility of component reuse.^66,75 They are responsible for evaluating the reuse of building components based on their capacity to meet current legislation and functional requirements. MEP engineers are often considered the most reliable professionals to implement circular building services.²⁸ Stiglmair and Jurkait⁵² suggested that MEP engineers collaborate with manufacturers to evaluate and test circular building services products.

Contractors play a crucial role in the on-site implementation of reuse practices.^63,66 Early involvement of HVAC contractors can provide valuable insights into the feasibility of reusing materials and components.²³ The use of warranties by contractors was also emphasised by Addis⁶⁹ to ensure an enabling environment for implementing circularity. Contractors must also conduct structural evaluations and assessments before installing reused products.⁷⁴ Demolition contractors are also crucial in ensuring effective deconstruction for material recovery.²⁸

Legislators and policymakers significantly influence the circular economy through regulations, standards, and incentives. Legislation around safety, energy efficiency, and environmental standards directly impacts the potential for reusing building services components.^28,69 Legislative clarity and enforcement are critical for incentivising contractors’ demand and manufacturers’ supply.^14,28,68

Other stakeholders within the construction sector also play essential roles in driving the adoption of circular practices. The responsibility of facility managers to operate and maintain HVAC systems means they play a vital role in ensuring that these systems remain efficient and aligned with circular principles throughout their lifecycle.^23,43 Secondary market owners and urban mining companies facilitate the reuse, recycling, and repurposing of HVAC components, ensuring that valuable materials are recovered and reintegrated into the economy.²³

Strategies

Overcoming the challenges of adopting CE principles in building services necessitates a multifaceted approach. Several frameworks and strategies have been proposed to guide this transition. Croxford et al.²¹ aligned with the Ellen MacArthur Foundation’s building block, emphasising circular design, advanced business models, aftermarket logistics, and enabling environments. Oosting²⁷ introduces a complementary perspective focusing on circular design, products, and business models. These strategies resonate with the earlier work of Webb et al.⁶⁴ Stiglmair and Jurkait⁵² outlined guidance for engineers to deploy CE principles in building services design but omitted approaches for reusing existing building services and components.⁴⁴ Rabie and Sjöholm²⁸ also provided a comprehensive overview of strategies identified by industry stakeholders to address various barriers to circularity in building services.

Findings from a case study investigation by CIBSE¹³ outlined five distinct scenarios to advance CE principles in building services. The joint venture scenario envisions a collaborative model where all project stakeholders unite under a shared financial framework. This approach optimises building performance through a ‘product as a service’ model, enhancing maintenance, extending system life, and closing the performance gap. The universal building scenario prioritises flexibility and adaptability in building design. This scenario maximises a building’s lifespan and potential for future use by focusing on simplicity. The passive scenario aims to eliminate mechanical HVAC systems by harnessing natural ventilation, daylight, and solar shading to reduce energy consumption and peak power demand.

The preloved scenario promotes the use of pre-owned or recycled materials in building services equipment while also ensuring the future recyclability of components. Finally, the recover scenario minimises primary resource consumption in building services systems by reusing waste resources, reducing operational costs, and recovering energy, water, and materials.

The various strategies identified to improve the application of circular economy in building services are represented in nine categories. These categories are analysed and integrated with the five distinct scenarios¹³ and four building blocks²¹ to develop a framework for improved application. The framework, presented in Figure 7, provides a structured model of approaches and strategies to enable and advance circular building services.

Figure 7.

A framework for advancing circular economy applications in building services.

The framework outlines the relationship between the identified nine strategies, five distinct scenarios (Joint venture, Universal building, Passive, Preloved, and Recover scenario) and four building blocks (Circular design, New business models, Reverse cycle, and Enablers). The Circular design building block integrates the Universal building and Passive scenario, aligning with the Design strategy. Life cycle costing strategy is also vital in the Universal building scenario. The New business model building block integrates the Joint venture scenario and aligns with three strategies: Warranties, Business model and Product information. The Reverse cycle building block integrates the Preloved and Recover scenarios, and Product information is an essential strategy for the Preloved scenario. The Enablers building block incorporates all the scenarios and strategies. This also applies to various identified strategies: Education, Policy, Digital technology, Collaboration and Transparency. The strategies identified from the publications and represented in the framework are discussed in detail below.

Design

Webb et al.⁶⁴ and Croxford et al.²¹ emphasise the importance of designing building services components with reuse in mind. This involves designing for disassembly or deconstruction to facilitate remanufacturing or refurbishment at the end of a product’s life.^{23,27,52,70,78} A holistic approach is crucial, extending beyond individual components to encompass systems and services.⁴³ Modular structures that enable easy disassembly and connection are also essential.^13,44,54 Ultimately, reducing the need for building services through passive design strategies is the most circular approach.^22,23

Business model

A transition to service-based business models is imperative for the circular economy. Manufacturers assume responsibility for maintenance and recycling by leasing rather than selling products, aligning economic incentives with environmental goals.^21,27,43 This approach minimises waste generation as products remain within the manufacturer’s supply chain.⁷³ Additionally, it offers users the advantage of performance upgrades and extended asset life.⁴³ Critical components of successful circular business models include value proposition, creation, and capture.⁷⁶ Viable options include leasing, pay-per-use, and renting.^22,54

Policy

Effective policy and regulatory frameworks are essential for fostering the adoption of CE principles in building services. Patil²³ and Rabie and Sjöholm²⁸ emphasise the need for clear government guidance and legislation that are not contradictory to encourage component reuse. Professional bodies also have a role in creating frameworks and standards, as exemplified by CIBSE⁴³ and UKGBC⁷³ in the lighting industry. Olnhoff and Martin⁶⁸ advocate for robust standards and incentives to promote industry participation in CE initiatives. While progress has been made, comprehensive and supportive legislation remains crucial.⁴³

Product information

Addis⁶⁹ and CIBSE²² highlight the complex nature of the supply chain and the need for a better understanding of component availability, pricing, and product information. Loreau et al.⁵⁰ emphasise the underdeveloped state of reuse supply chains, advocating for improved tracking of material flows. Manufacturers are crucial in providing detailed product information and ensuring compliance with safety and efficiency standards.⁶⁹ Material and product passports, along with clear labelling, offer valuable insights into product history, environmental impact, and reuse potential.^23,27,44,52

Warranties

Warranties are pivotal in building trust and confidence in reused components. Addis⁶⁹ highlights the importance of manufacturers providing warranties for reused products. CIBSE⁴³ emphasises the need for long-term warranties to create a favourable environment for reuse. Performance guarantees can also incentivise circularity by mitigating risks and building stakeholder confidence.^28,65

Life cycle costing

Life cycle costing and assessment are essential for evaluating the environmental and economic performance of building services. Theißen et al.¹⁴ and CIBSE¹³ emphasise the role of these assessments in driving systemic innovation towards reuse. Conducting life cycle assessments as an initial step in CE initiatives is recommended.⁷³ This holistic approach enables the identification of components with more excellent long-term value and reuse potential.²³ These assessments promote sustainable decision-making by considering the total cost of ownership, including maintenance, operation, and disposal.⁵⁴

Digital technology

Digital technologies are emerging as critical enablers for advancing CE principles in building services. Theißen et al.¹⁴ and CIBSE¹³ emphasise the role of Building Information Modelling (BIM) and other intelligent technologies in facilitating data-driven collaboration. Digital building manuals, enabled by these technologies, enhance tracking of component usage, maintenance history, and material properties, which is crucial for assessing reuse potential.⁷⁹ Digital platforms connecting buyers and sellers of reused products are also essential.⁶⁷ CIBSE²² highlights BIM’s role in generating life cycle data, streamlining operations, and supporting facility management with data storage.^21,23

Education

Kaarmila⁷⁹ emphasises educating stakeholders, including designers, contractors, and facility managers, about the benefits of reuse and CE practices. This knowledge is essential for early goal-setting, reuse planning, and on-site management to enable circularity.⁴⁴ Raising public awareness is also crucial for creating demand and ensuring successful circular products and services,¹³ which is a part of the responsibility of professional bodies.⁴³ Jurkait and Stiglmair⁷² identified that awareness of circularity criteria, materials choices, and building services systems applications will enable increased adoption. Effective communication and training are vital to developing a knowledgeable workforce capable of implementing reuse strategies.^43,79

Collaboration and transparency

The effective implementation of CE principles in the building services sector requires strong collaboration and transparency among stakeholders. Patil²³ highlights the importance of cooperation between designers, contractors, manufacturers, and end-of-life management parties. Croxford et al.²¹ emphasise that a fragmented approach can hinder progress, underscoring the need for close collaboration across the value chain.¹³

Gap analysis

The systematic literature review also identified some research gaps after analysing the current state of knowledge on the application of circular economy to close the resources loop in building services.

The SLR observed the dominance of strategies and guides for new construction and HVAC installations within the literature. The guideline by Stiglmair and Jurkait⁵² for engineers to deploy CE principles also excluded existing building services and components.⁴⁴ However, about 80% of buildings that will exist by 2050 have already been constructed.⁸⁰ Many of the installed HVAC systems in these buildings will still be replaced and may already be obsolete, and they will not achieve the necessary standards to enable circularity.²³ While Afify⁷⁰ examines the likely scenarios faced when an engineer attempts to reuse existing HVAC systems, no research has provided clear guidance.

The need to reinvent business models to enable CE in building services is firmly established in the literature.^21,27,54,76 Guidance has also been provided to implement new models, such as lighting as a service.⁷³ However, an evidence gap is observed, and no research has been conducted on the cost-benefit analysis of deploying these new business models within building services. Do manufacturers make a profit when they deploy new business models? How do clients trust suppliers regarding cost and performance? What barriers are experienced within real-life implementations of new business models? Evaluating and documenting this evidence is essential for advancing public awareness and stakeholder perceptive, ultimately increasing the current limited adoption.⁴³

An empirical gap in the application of digital technologies to enable a circular economy in building services is also observed in the review. Croxford et al.²¹ and CIBSE⁴³ outlined that BIM and other digital tools are vital for improving recyclability, streamlining operations, and optimising information management to advance circular building services. Kaarmila⁷⁹ and Patil²³ also emphasised using BIM and digital building manuals to track material properties, component usage, maintenance history and evaluate reusability. However, BIM models often oversimplify the components of building services.²⁸ Yet, only Theißen et al.¹⁴ have examined the use of BIM to advance circular building services. Also, research on the application of other digital technologies, like artificial intelligence, addictive manufacturing, digital twins, blockchain, and the Internet of Things, to advance circular building services is non-existent. This presents an empirical gap and highlights the need for more research on integrating digital construction technologies to enable a circular economy in building services.

As earlier identified by the review, the application of CE in building services is still in its infancy. As such, while the identified gaps may be inevitable, they provide a vital research direction to consider for improved implementation of circular building services.

Conclusion

The systematic literature review has outlined the current state of knowledge on closing the resourcing loop in building services, which is a component for ensuring comfortable and safe internal building environments. The review identified the current application of CE in building services, recurrent barriers and opportunities, key influencers, and strategies for improved application. After a 3-stage literature screening from two databases and external sources, 29 publications were included in the review. While this review offers an exhaustive evaluation of the state of knowledge regarding the application of circular economy in building services, the limitation to only literature published in English may have excluded relevant articles. Also, while the addition of publications from external sources enriched the review, relevant literature may have been omitted due to the requirements to define exclusion and inclusion criteria when conducting a systematic review.

The findings from the review indicate that while the adoption of circularity in building services has attracted attention in recent years, the research efforts within this industry are still nascent, especially when compared to the research on broad CE applications in construction. Exploratory research and guidelines are the highest publication outputs, representing the need for pragmatic solutions. The concentration of research within Europe can be attributed to public policies and legislation driving market demand and need. Even though building services are characterised by a complex supply chain, most solutions for advancing CE within the broad construction sector also apply.

Four key themes were identified from the review, including barriers and opportunities, key influencers, and strategies for advancing and enabling circular building services. Based on the similarities, the barriers were categorised into four axes: technical, economic, legislative, and organisational. The technical barriers are mainly product obsolescence, rigorous maintenance, performance gaps, lack of standardised methods, and complex retrofitting processes. The need for technical modifications and possible increased energy consumption that building services components may exhibit when reused were also identified. Also, when conducting life cycle assessments, building services are sometimes omitted or represented in simplified manners because of the complexity of manual calculations and lack of granular information. Economic barriers were also identified as part of the limitations for circular building services. The high cost, logistics impact, low volume, and short lifespan of building services products often inhibit circularity. The absence of a secondary market and no clarity of financial incentives also pose economic barriers.

Stringent performance standards and policies often result in legislative barriers. Older building services frequently fall below the necessary targets for energy efficiency, thermal comfort, and energy consumption. The absence of performance-based specifications, standardised environmental auditing, and clear policy guidance exacerbates these issues. Organisational culture and entrenched practices and mindsets also hinder circular building services. The lack of knowledge sometimes results in clients and professionals restricting the implementation of circularity. An apathy towards environmental issues and the fragmented supply chain also hinders. The need for committed professionals across the building services supply chain remains a deterrent to applying a circular economy.

Beyond these barriers, the review identified various opportunities for implementing a circular economy. Implementing circular practices should minimise waste, reduce demand for virgin materials, lower emissions, and enable resource-efficient construction. Economic benefits are also envisaged, like reducing capital cost and price volatility risks and ensuring long-term resource availability. New business models are also expected to emerge, unlocking market development and economic opportunities. Deploying digital technologies for circularity also ensures effective manufacturing, construction, operations and lifecycle information management.

While a collaborative effort is required across the entire supply chain, six professionals are considered key influencers for circular building services. Clients and building owners are pivotal for creating the demand and spurring necessary commitments across the supply chain. Manufacturers can influence innovations through product design, policy alignment, resource efficiency, and reducing product emissions. Design teams, comprising architects and planners, are essential to the most critical stage to influence circularity. MEP engineers are regarded as the most reliable in implementing circular economy by ensuring the necessary evaluation of functionality and legislative compliance. Contractors, both for installation and demolition, can ensure on-site implementation and effective deconstruction. Legislators create the enabling environment through policies and incentives.

The review developed a framework for advancing circular economy in building services, integrating the nine strategies identified with existing principles and building blocks. Strategies like design for disassembly, passive, and modularity must be adopted during the design stage. Service-based business models, such as leasing, product-as-a-service, and renting, would ensure that products remain within the manufacturer’s supply chain, and they assume responsibility for maintenance and recycling. Policies and regulatory frameworks must not contradict circularity objectives but encourage and incentivise. Systems, like material passports and labelling, must be adopted to provide insights into history, environmental impacts, and product reuse potential. Warranties and performance guarantees build trust and confidence for reused products.

Other strategies included in the framework include detailed life cycle cost assessments to evaluate building services products’ long-term value and environmental impacts. Adopting digital technologies is also vital to facilitate data-driven collaboration, track usage, connect demand and supply, and store life cycle data for efficient operations and management. Educating stakeholders and raising public awareness is essential; this responsibility also lies with professional bodies. Finally, collaboration and transparency between all stakeholders are necessary for advancing the shift to a circular economy. The strategies outlined in the framework are pivotal for enabling circular building services.

Various research gaps identified from the review offer further areas of concentration and evaluation. Guidelines are required to enable the reuse of existing building services. Evidence-based research into deploying new business models is essential to increase adoption. Empirical research on deploying multiple digital construction technologies to enable a circular economy in building services is also vital. Ultimately, new skills, shifts in mindset and holistic solutions are required to advance and enable the application of circular economy in building services.

Footnotes

Acknowledgements

The authors of this paper would like to thank the European Union for funding COST (European Cooperation in Science and Technology) and for supporting the COST Action CircularB CA21103 (), and the Vice Chancellor of Ulster University for funding the doctoral study.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iDs

Moses Itanola

Philip Griffiths

Ibrahim Motawa

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