Analysing multifaceted barriers to modular construction in sustainable building projects: a comprehensive evaluation using multi-criteria decision making

Modular construction (MC) is recognized as pivotal for sustainable development in developed countries. However, its implementation faces barriers in residential projects in developing nations. This study aims to address the knowledge gap resulting from the limited uptake of MC in residential projects, mainly attributed to existing barriers. To accomplish this goal, a questionnaire survey was conducted to assess the significance of thirty adoption barriers. Subsequently, an exploratory factor analysis method was applied to categorize these barriers, followed by their assessment and ranking using fuzzy synthetic evaluation. A novel aggregation and ranking method that integrates the WASPAS and TOPSIS techniques for order preference, by similarity to an ideal solution approach, was employed. The rankings derived from different decision-making methods were combined using an ensemble approach based on half-quadratic theory. Our findings reveal that the adoption barriers can be grouped into five main categories, with cost, coordination, and standards emerging as the most prominent barriers. They are followed by technical and practical barriers, inflexibility and supply chain barriers, abilities and awareness barriers, and societal and desire-related barriers. The study results offer significant insights into the barriers impeding MC adoption in developing countries' construction sectors, providing recommendations to improve its uptake.