BIM-Based Quantity Validation for Smart and Sustainable Infrastructure Delivery
Manual quantity take-off (QTO) for building projects typically requires repeated interpretation of architectural drawings and transfer of measurements to spreadsheets or databases, which can limit traceability and increase the risk of preventable errors. This study investigates whether Building Information Modeling (BIM) can provide a reliable quantity-validation approach to support smarter and more resource-efficient infrastructure delivery in a healthcare building project. A BIM model of major structural and architectural work packages was developed in Autodesk Revit using a maternity hospital building in Boyolali, Indonesia, as the case study. Model-derived quantities were first validated against manual calculations and then compared with consultant-reported quantities. The validation stage showed very strong agreement between manual and model-based quantities, with correlation and coefficient-of-determination values of at least 0.99. However, substantial discrepancies were identified for grade beams (52.66%), base concrete work (42.04%), and bore piles (32.94%), corresponding to a potential cost exposure of IDR 3,088,177,992.10 (18.72%).