Optimizing design decisions for construction waste minimization through an interpretive structural modelling approach

Purpose: Information gaps hinder effective decision-making in minimizing construction waste (CW) in building projects. The existing literature has not sufficiently explored these gaps or the strategies to address them. This paper aims to investigate the critical reasons for these gaps and identify top-level strategies to bridge them, emphasizing their interrelationships during the building design stage to effectively minimize CW. Design/methodology/approach: A survey inviting 30 experts from the Australian construction industry, each possessing over 15 years of experience and at least 8 years in waste minimization (WM). The survey yielded 15 responses for interpretive structural modelling (ISM), resulting in a 50% response rate. The qualitative evaluation prioritized specialist insights over quantity, in line with previous research. ISM facilitated the formation of a hierarchical model, while Matrice d’Impacts Croisés-Multiplication Appliquée à un Classement (MICMAC) analysis was employed to assess influencing factors. Findings: The findings indicated that knowledge gaps, technical issues and collaboration challenges are significant reasons for existing information gaps in decision-making related to minimizing CW. Additionally, “gaps in information” and “time pressure” are primary drivers of these issues. Although “defining stakeholder engagement” emerged as a key strategy to bridge these gaps, it exhibits low driving power. Research limitations/implications: These research findings make significant contributions by identifying top-level reasons for information gaps and proposing strategies to mitigate them within the design decision-making process, ultimately aiming to minimize CW. Additionally, the article aspires to furnish both academia and practitioners with an intensive comprehension; utilizing ISM and MICMAC analysis unveils intricate interdependencies, thereby paving the way for a deeper understanding of these phenomena and fostering ongoing discourse in the realm of CW minimization research directly contributing towards populating novel concepts as net zero carbon practices. The study was limited to decision-making at the design stage of commercial buildings. Practical implications: This study contributes novel insights to existing literature, offering valuable guidance to decision-makers during the design phase. Tailored strategies, aligned with specific considerations, furnish practical information to stakeholders within the design team, thereby enhancing the efficiency and effectiveness of decision-making processes. Ultimately, these contributions advance the building construction industry by facilitating the minimization of construction waste. The significance of integrating all findings to derive clear interpretations is highlighted, emphasizing the positive impact of interconnected strategies in addressing the overarching goal of waste minimization in construction projects. Originality/value: This study contributes original insights by investigating critical reasons for information gaps and strategies to bridge them in building design decisions, enhancing decision-making processes in the construction industry through ISM and MICMAC methodologies.