Simulation based multi-objective cost-time trade-off for multi-family residential off-site construction

Off-site construction is a shift toward a more efficient building process in terms of minimizing cost and decreasing duration of projects. However, since off-site construction consists of two separate phases, a comprehensive cost-time trade-off is essential. It gives control for the overall process where the direct and indirect effect of work performed on an individual task can be measured and evaluated with respect to the final project performance factors. The research presented in this paper develops a simulation model to study the dynamic relationship between off-site manufacturing and cost-time trade-off. A multi-objective analysis for two main indirect costs and inventory cost of the manufactured building components are proposed in order to provide a decision support system tool to clarify any ambiguity in the dynamic relationship between the project´s two stages, and assist the manager to improve project planning and control.