What is air leakage? Why is it important?

Air leakage is the damper’s ability to close tightly to limit the amount of air passing through the damper.

In other words, Air Leakage is that wisp of air that get through the closed blade damper.

There will always be some air leakage, since no damper is airtight, but too much leakage can cause trouble. If left unchecked, this leakage can hinder performance and cause excess strain on your HVAC system.