A dryer vent that never gets cleaned isn't just a slower way to dry clothes, it's a genuine fire risk. Lint is highly flammable, and once it builds up inside a duct that's also generating heat, all the ingredients for a fire are already in place. The U.S. Fire Administration reports roughly 2,900 residential dryer fires a year, causing about 5 deaths, 100 injuries, and $35 million in property damage, and failure to clean the vent is the leading cause, responsible for about 34 percent of them. It's also one of the most preventable house fires there is.
Warning signs to watch for
- Clothes take two or more cycles to dry, or come out still damp
- The dryer or the clothes feel unusually hot to the touch
- A burning or scorched smell during a cycle
- The exterior vent flap barely opens, or you notice lint built up around it
- Lint collecting behind the machine or around the duct connections
If you notice a burning smell, visible smoke, or the dryer shutting off mid-cycle while hot, stop using it and address the vent before running it again.
How often to clean it
Once a year is the general rule. If you have pets, a large household, or run the dryer especially often, every 6 months is a better interval.
What cleaning involves
- Unplug the dryer and, for gas dryers, shut off the gas supply before disconnecting anything.
- Pull the dryer away from the wall and disconnect the duct from the back of the machine.
- Vacuum out the lint trap housing and the duct opening on the dryer itself.
- Run a dryer vent brush kit through the full length of the duct to loosen and pull out built-up lint, working from both ends if you can reach them.
- Go outside and clean the exterior vent hood, then check that the flap opens and closes freely.
- Reconnect everything, plug the dryer back in, and run a cycle to confirm strong airflow at the outside vent.
Check what your duct is made of
While you're back there, take a look at the duct material itself. Rigid or semi-rigid metal is the safe standard. Thin foil flex duct traps lint more easily and can restrict airflow, and plastic or vinyl duct is banned by most building codes because it burns readily and can melt. If you find either of the latter two, it's worth replacing with rigid or semi-rigid metal duct rather than just cleaning around the problem.
When to call a professional
If your duct run is long, passes through walls or multiple floors, or you simply can't get a brush through the full length yourself, a professional dryer vent cleaning service has the equipment to do a complete job from both ends and confirm the airflow is where it should be.
