Factors Causing Waste in Construction of Mega-Projects: Case Studies from Saudi Arabia

The construction industry continues to generate vast volumes of waste, which harm the environment and negatively impact socio-economic sustainability, especially in a developing country like Saudi Arabia. Prior to investigating effective approaches for managing waste, we must identify the main drivers of construction waste. This paper develops metrics and criteria for identifying and ranking the waste cause factors (WCFs) in the construction of mega-projects in Saudi Arabia. The methodology adopted includes a thorough literature review and a survey ranking waste factors based on a five-point Likert-scale. Data collected from 239 participants across three distinct construction mega-projects were analysed using one-way analysis of variance (ANOVA) with its corresponding post hoc tests, and the identified waste factors were ranked according to their relative importance index (RII). The findings of this study indicate that the main sources of waste in Saudi Arabia involve design changes and complexity, poor project coordination, inefficient waste management systems, lack of supervision, drawing errors, low skill levels among workers and designers, and procurement mistakes. The results and discussions derived from the investigation aim to deepen the understanding of the causes of waste in large-scale construction, which could inform researchers, policymakers, and professionals, whose joint contributions should enable effective waste management strategies in large construction projects.