A Study on Optimizing Cost Calculation for BIM-based Modular Buildings Using DfMA Standard Modules

This study proposes a cost optimization approach to address the issue of price escalation in small-scale modular construction through the application of Design for Manufacture and Assembly (DfMA) standard modules and Building Information Modeling (BIM). Focusing on light- weight timber-frame single-family houses, the research standardizes module unit sizes and structural details, and builds a BIM model based on these standards. A process for accurately calculating estimates, manufacturing costs, and order quantities was developed using BIM-based quantity takeoff. This process was validated through the creation of virtual design proposals, demonstrating real-time accuracy in cost estimation. The study aims to enhance the economic viability of modular construction and prevent cost escalation issues that may arise during the initial design phase. Future research should address additional cost estimation methods for components such as windows and furniture, and explore simpler modeling techniques and optimized material cost research.