Investigation of Material Waste at Source in Offsite Construction: Quantification, Analysis, and Mitigation

Hadi, Ali Abdulzahra (2026) Investigation of Material Waste at Source in Offsite Construction: Quantification, Analysis, and Mitigation. Doctoral thesis, Birmingham City University.

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Abstract

Offsite construction (OSC) has long been recognised for its potential to deliver environmental benefits, including reductions in material waste. However, existing research provides limited understanding and quantification of material waste generation in OSC. Although several studies have analysed OSC from a lean perspective, their evidence remains fragmented, with limited dedicated analysis of material waste. Other research has quantified material waste in OSC, but the analysis has mainly compared site-based waste generation with that of traditional construction, overlooking the waste generated offsite. Therefore, evidence on how, how much, and why material waste is generated in OSC remains highly limited. The lack of evidence impedes efforts to develop targeted interventions to support waste reduction. Hence, this study aims to develop an empirical understanding of material waste generation at source in OSC by quantifying waste, identifying its root causes, and suggesting targeted interventions to support waste reduction. By conducting empirical investigation across four OSC factories, the study identified five categories of material waste, each mapped to its root causes to explain how it is generated, reduced, or avoided. Key findings reveal that: 1) a poorly integrated design process causes significant material waste due to mismatches with available material sizes and inadequate detailing for assembly; 2) rigid procurement limited to a narrow range of standard and custom sizes restricts the design team’s ability to reconcile customer-specific requirements with material availability, thereby increasing material waste; 3) inadequate production capabilities, particularly in material nesting and cutting precision, further drive waste generation; and 4) the prioritisation of production flow often overrides material-efficiency efforts, leaving even proven automated waste-saving technologies underused. Theoretically, this study advances knowledge by offering detailed source-level quantification and analysis of material waste in OSC, thereby deepening understanding of how waste is generated, reduced, and avoided. In doing so, it establishes a grounded evidence base for future research to propose and test interventions aimed at reducing material waste at source in OSC. Practically, the study recommends adopting: 1) a pull-based design process that aligns design decisions with procurable material sizes and production capabilities; 2) an agile procurement process capable of sourcing a wide range of standard and custom material sizes; and 3) efficient production capabilities that enhance material-efficiency without compromising production flow. Collectively, these integrated design, procurement, and production practices act as a protective mechanism to reduce material waste at source in OSC, which would otherwise necessitate significant downstream reuse and recycling efforts to be mitigated.

Item Type:	Thesis (Doctoral)
Dates:	Date Event 23 March 2026 Accepted
Uncontrolled Keywords:	Material Waste; Offsite Construction; Waste reduction; Waste Quantification
Subjects:	CAH10 - engineering and technology > CAH10-03 - materials and technology > CAH10-03-02 - materials technology CAH10 - engineering and technology > CAH10-03 - materials and technology > CAH10-03-07 - materials science CAH13 - architecture, building and planning > CAH13-01 - architecture, building and planning > CAH13-01-02 - building
Divisions:	Architecture, Built Environment, Computing and Engineering > Architecture and Built Environment > Built Environment Doctoral Research College > Doctoral Theses Collection
Depositing User:	Louise Muldowney
Date Deposited:	13 Apr 2026 09:01
Last Modified:	13 Apr 2026 09:01
URI:	https://www.open-access.bcu.ac.uk/id/eprint/16962

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