Dryer exhaust ducts must terminate on the outside of the building and be equipped with what kind of device?

Dryer exhaust ducts are crucial in ensuring that the hot, moist air created by the dryer is safely vented outside the building. When these ducts terminate on the outside, they must be equipped with a backdraft damper to prevent outside air from flowing back into the duct.

A backdraft damper allows air to flow out of the duct when the dryer is running, but it closes firmly when the dryer is off. This prevents drafts, which can lead to reduced heating efficiency and increased energy costs. It’s essential for maintaining controlled indoor air quality and preventing potential issues like mold growth or cold air infiltration during winter months.

In addition to energy efficiency and comfort, the installation of backdraft dampers can also reduce the risk of fire hazards associated with lint buildup in improperly vented dryer systems. Proper venting is a key component of safe appliance operation, making the backdraft damper an important feature in maintaining dryer exhaust ducts according to code requirements.