The renovation plan included adding new ductwork that would connect to thousands of feet of existing ductwork located in a sub-basement space just below the convention room floor. Unfortunately the old ductwork was rife with leaks, and engineers knew that it would not accommodate the added pressure created by the new VAV system. They also knew that replacing the ductwork or sealing it using traditional methods would add months to the project schedule and tens of thousands of dollars to the budget.