Modeling and representation of non-value adding activities due to errors and changes in design and construction projects

Non-value adding activities which consume time and/or resources without increasing value, have been considered as main contributors to schedule delays and cost overruns in design and construction projects. While these activities are mainly triggered and proliferated by errors and changes, traditional construction management approaches have not explicitly addressed the impact of errors and changes on non-value adding activities. To capture non-value adding activities due to errors and changes, a system dynamics based simulation model is developed and presented in this paper wherein the impact of non-value adding activities are intuitively visualized in a colored bar chart. The developed model is applied to a bridge project in Massachusetts. The simulation results show that errors and changes resulted in 26.1% of non-value adding activities and 171 days of schedule delays in this project. Based on these simulation results, it is concluded that the developed simulation model holds significant potential to aid better decision-making for controlling non-value adding activities in design and construction projects.