How often should you clean your dryer vent?

Clean the full vent duct at least annually, and more often if you run many loads, have pets, or have a long or convoluted duct run to the exterior. The lint screen catches a fraction of the fiber shed during drying; the rest accumulates inside the duct, where it restricts airflow and eventually contacts a heat source. US fire departments respond to thousands of dryer fires each year, and failure to clean is consistently identified as the leading cause. This is one of the few maintenance items where neglect has an ignition risk rather than a repair bill.

The warning signs are specific and easy to notice once you know them: clothes taking noticeably longer than one cycle to dry, the dryer or the laundry room becoming unusually hot, a burning smell, and the exterior vent flap not opening fully when the dryer runs. Beyond annual cleaning, two design factors matter more than most people realize. Flexible foil or plastic accordion ducting traps lint in its ridges and is prohibited by many codes; rigid or semi-rigid smooth metal duct is the correct material. And the shorter and straighter the run, the safer and more efficient it is, since every elbow adds resistance and a collection point. Clean the lint screen every load, and wash it with soap occasionally, since fabric softener leaves an invisible film that restricts airflow through the mesh.