Construction Project Cost Escalation Factors

Construction projects, private and public alike, have a long history of cost escalation. Transportation projects, which typically have long lead times between planning and construction, are historically underestimated, as shown through a review of the cost growth experienced with the Holland Tunnel. Approximately 50% of the active large transportation projects in the United States have overrun their initial budgets. A large number of studies and research projects have identified individual factors that lead to increased project cost. Although the factors identified can influence privately funded projects the effects are particularly detrimental to publicly funded projects. The public funds available for a pool of projects are limited and there is a backlog of critical infrastructure needs. Therefore, if any project exceeds its budget other projects are dropped from the program or the scope is reduced to provide the funds necessary to cover the cost growth. Such actions exacerbate the deterioration of a state’s transportation infrastructure. This study is an anthology and categorization of individual cost increase factors that were identified through an in-depth literature review. This categorization of 18 primary factors which impact the cost of all types of construction projects was verified by interviews with over 20 state highway agencies. These factors represent documented causes behind cost escalation problems. Engineers who address these escalation factors when assessing future project cost and who seek to mitigate the influence of these factors can improve the accuracy of their cost estimates and program budgets.