Environmental, Social and Governance (ESG)-Oriented Decision Support in Off-Site Construction: A Lifecycle-Integrated Architecture

Abstract

Off-site construction (OSC) changes not only where construction activities are performed, but also how project decisions are distributed across the lifecycle. Decisions made during design and planning can shape manufacturing, logistics, on-site assembly, and operation, yet the knowledge needed to support these decisions is often dispersed across lifecycle stages, project teams, and information systems. This fragmentation becomes more critical when project teams are expected to consider environmental, social, and governance (ESG)-oriented value trade-offs, because such trade-offs are embedded in decision processes rather than confined to post-project performance evaluation. Existing decision support approaches in construction have advanced data integration, modelling, and analytical capability, but they remain limited in their ability to mobilise heterogeneous lifecycle and ESG-oriented knowledge in response to specific OSC decision contexts. This paper develops a lifecycle-integrated decision support system (DSS) architecture for supporting ESG-oriented decision-making in OSC projects. Adopting a problem-driven conceptual design approach informed by design science principles, the study proceeds through problem structuring, requirement derivation, and architecture synthesis. The main conceptual output is a lifecycle-integrated DSS architecture comprising three connected components: heterogeneous knowledge sources, a lifecycle-integrated knowledge base, and a retrieval-augmented generation (RAG)-enabled decision support engine. The architecture organises project knowledge around lifecycle stages, decision contexts, and knowledge domains, allowing ESG-oriented value trade-offs to be embedded within decision-relevant knowledge rather than treated as external evaluation criteria. The RAG-enabled decision support engine is designed to retrieve and synthesise relevant lifecycle, ESG-oriented, and project-context knowledge for specific decision situations. The study contributes by reframing ESG-oriented decision support in OSC as a problem of lifecycle knowledge structuring and context-specific knowledge integration. It provides a conceptual foundation for future prototype development, expert validation, and empirical testing.