The issue commonly encountered in the execution of construction projects is the presence of waste. This waste manifests in activities that consume resources without adding value to the project. Addressing the prevalence of waste is crucial as it can disrupt the construction process. An effective strategy is needed to eliminate or minimize waste by enhancing efficiency through value-added activities. This study aims to examine the factors contributing to waste and identify common waste occurrences in the construction of the Maternal and Child Building at ISDB IDN 1031 RSUP Dr. Sardjito. The Borda method is utilized to rank the dominant waste variables and factors, while the 5-Whys root cause analysis method is employed to investigate the root of the waste. The findings reveal that transportation, defects, and motion are the most significant waste variables in the project, with proportions of 0.254, 0.2178, and 0.1851, respectively. The root cause analysis identifies limited access as the primary cause of transportation waste, while a lack of skilled workers leads to defects. Workers’ unnecessary movement is found to be the root cause of motion waste.