<p>The modular housing approach involves a network of stakeholders with different key roles, requirements, information, and activities. Despite its potential to revolutionize the housing sector, there is limited knowledge on how to effectively implement modular housing in specific contexts, such as Saudi Arabia. This gap necessitates a comprehensive investigation of the critical success factors that drive project success. This study examines the critical success factors (CSFs) that enable the effective adoption of modular housing in Saudi Arabia’s residential projects. Relative Importance Index (RII) rankings and Principal Component Analysis (PCA) are used to capture both perceived importance and interdependencies among factors. The analysis reveals a clear CSFs hierarchy led by Adequate planning and context‑specific design, Proper site preparation and foundations, High‑quality materials and components, Effective project management, and Skilled and experienced labor. In Saudi Arabia’s climate and regulatory context, the leading CSFs imply actionable priorities: design for extreme heat and sandstorms, early compliance with Saudi Building Codes (SBC), and energy‑efficiency alignment with national guidelines. The study’s findings will guide policymakers, investors, and industry practitioners toward optimizing strategies for modular housing, thus contributing to Saudi Arabia’s housing sector development. The insights could also serve as a foundational framework for future research and practical applications in modular housing, emphasizing its role in enhancing sustainable and affordable housing solutions in the region.</p>