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Leveraging tech in maximising construction material reuse

Harnessing digital tools for material reuse is crucial. What technologies can help acquire information needed for reusing building components?

The construction industry consumes 46% of the world’s raw materials and creates approximately 26% of global greenhouse gas emissions. Reusing materials used in construction is desperately needed to reduce the environmental impact of the industry, and a circular economy approach would help keep resources in use for as long as possible before irreversible disposal. Simply recycling materials often involves high amounts of energy to reprocess the materials. In this research, we reviewed tools and techniques to explore how to increase reuse in construction. We investigated what properties are most important for reusing materials, what information is needed to enable them to be reused most effectively, and how they can be reused more effectively in practice.

Reusing materials in practice is challenging because materials are not standardised and cannot be easily interchanged. The logistics of extracting and distributing used materials are complex and costly, and additional liability must be assumed to ensure that reused components are appropriate and safe. Enormous amounts of information are needed about these materials to understand how they can be used in a new construction. However, new digital technologies can assist in collecting and storing this information.

The need for a digital transformation

Building materials can be reused in multiple buildings, but information about their properties and availability needs to be available to users. The reuse of building materials is often limited by the lack of reliable, accurate, and accessible data about them between the end of life of one building and the beginning of life of another (Figure 1). Transforming these physical processes to digital processes may enable better transfer of information along the life cycle of materials.

Figure 1. Possible Material Lifecycles
Credit. Author

The digitalisation of information is critical for minimising waste and conserving resources. Research on Industry 4.0 for circularity in the architecture, engineering, and construction (AEC) industry is increasing but has yet to influence practice widely. Technology can help scale up and expedite processes necessary for the transition towards a circular digital built environment. Yet this transition presents additional challenges: the labour force needs to acquire new skills, expensive tools must be made available, and processes need to be streamlined for efficiency.

We created a framework of categories for specific reuse actions to structure our research (see Figure 2). The framework includes manual and digital techniques from systematic literature reviews, published case studies, and real-world examples. We applied these techniques to eight case studies to explore the suite of approaches for information acquisition for material reuse.

Figure 2. Research Framework
Credit. Author

Integrating Industry 4.0 technologies in AEC

Industry 4.0 marks the advent of intelligent digital technologies connected over networks. There is no universally accepted list of technologies included within this wave, let alone the specific suite of technologies applicable for AEC, colloquially referred to as Construction 4.0. These technologies can be used in all processes, though only some are useful for the characterization, tracking, and assessment of reusable materials and are in Table 1.

Manual information acquisition techniques are much more common than digital techniques in current practice. Documentation methods such as building drawings and specifications, product data sheets, and environmental product declarations are the most common. Often, inspection reports and photographs are used to capture additional basic information while a building is being used. Table 1 summarises manual and digital approaches to information acquisition.

Information SourceApproachSource Examples
Data sheets and documentationManualDrawings and Specifications, Archives, Manual Inspections, Public Records, Material Passports, Environmental Product Declarations (EPDs), Product Data Sheets, Interviews and Surveys
Data modelling and storage systemsDigitalComputer-Aided Design (CAD), Building Information Modelling (BIM), Digital Twin Modelling Systems, Common Data Environment (CDE), and blockchains
Destructive and non-destructive testingManual and DigitalGround Penetrating Radar (GPR), Core Sampling, Tension and Bending Testing, Radiography, Dye Penetration
Spatial data acquisitionDigitalLiDAR, SLAM (Simultaneous Localization and Mapping), Terrestrial Laser Scanning (TLS), Photogrammetry, UAV (Unmanned Aerial Vehicles), Geographic information systems (GIS)
Artificial intelligenceDigitalTime-series Forecasting, Big Data Analytics, Object Detection
Internet of Things (IoT)DigitalMobile Sensing, Track and Trace, Radio-frequency identification tags
Table 1: Material Information Sourcing Strategies

Findings from case studies

We examined several studies of successful implementation of building material reuse for the approaches taken, the type of information used, and specific actions related to reuse. We conducted semi-structured interviews to compare patterns observed from the studies to eight empirical reuse examples.

In total, six classes of material properties were found to be useful for material assessments for reuse: physical (e.g., geometric), economic (e.g., labour/material costs), environmental (e.g., embodied carbon savings), mechanical (e.g., strength), chemical (e.g., rust/corrosion), and temporal (service life). Of all these property classes, the two most significant to justify material reuse were the physical and economic properties.

In addition, we identified five specific actions essential for building material extraction and subsequent reuse (see Figure 3). These properties and actions help us understand what information is needed to facilitate reusing building materials.

Figure 3. Taxonomy of Information Acquisition for Reuse
Credit. Author

Implications for the future of circular construction

Research indicates that while traditional methods still dominate material information acquisition in construction, there’s potential for digital tools to streamline the process. Embracing digital transformation could enable the industry to scale up material reuse effectively. To achieve this, the construction sector must prioritise upskilling its workforce to leverage digital technologies. Furthermore, adopting a more integrated approach incorporating sustainable principles from the design phase is essential. Collaboration among stakeholders, including material suppliers, contractors, and policymakers, is crucial for fostering innovation and embracing circular practices.

Reuse of building elements at a larger scale is hindered by information gaps between building use cycles. The lack of preserved building records with comprehensive information detailing material composition, service life, and load exposure prevents the specification of reused elements in new construction projects.

Brandon S. Byers

Regulatory frameworks and standardisation processes need to adapt to endorse material reuse, which includes revising building codes, warranties, and liability regulations. Policies should promote standardised documentation practices to ease material reuse. Furthermore, incentives arising from policies supporting sustainable and circular practices could catalyse broader transformations in the AEC sector. Embracing a circular economy in construction not only enhances environmental sustainability but also delivers economic and social advantages, aligning the industry with global sustainability objectives and fortifying the resilience of the built environment.

Steps for facilitating the reuse of construction materials

Transitioning to a circular digital built environment requires integrating research, policy, practice, and new technologies. By addressing the current gaps in research and practice, regulatory barriers, and the need for digitalisation, stakeholders can pursue more sustainable consumption and production in construction. Three steps should be considered for digital and circular transformations:

  1. Promote knowledge sharing and collaboration: Information needs to be made more accessible. Sharing knowledge through workshops and reports will build trust and awareness amongst stakeholders and continue to be a best practice for reuse.
  2. Develop policies and standards: Reuse processes need to be standardised for use in practice. Developing policies would help guarantee the quality of reuse projects.
  3. Start early: Consider material reuse early in the design phase. Start with the minimum information needed to reuse materials and choose the best tools to implement reuse.

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Journal reference

Byers, B. S., Raghu, D., Olumo, A., De Wolf, C., & Haas, C. (2023). From research to practice: A review on technologies for addressing the information gap for building material reuse in circular construction. Sustainable Production and Consumption. https://doi.org/10.1016/j.spc.2023.12.017

Brandon Byers is a Doctoral Researcher at ETH Zurich, Switzerland, in the Chair of Circular Engineering for Architecture. He holds additional degrees in Civil Engineering from Georgia Tech and Sustainable Design & Construction from Stanford University. His research focuses on building informatics and distributed technologies for product tracking to facilitate a circular economy in construction.