In this brochure, the advantages of performance testing of duct systems are discussed. Some of the topics discussed include, "Why is measuring duct leakage important?" "Where does duct leakage occur?" and "How much can energy bills be reduced by sealing duct leaks?" Actual photos of duct leaks, duct systems, and how to test ducts are shown. In addition, the brochure uses diagrams of construction details to show paths of leakage of the duct system and how the building envelope can contribute to poor performance by entrainment of outside air into the ductwork.

- The Energy Conservatory