How to Clean a Dryer Vent (and Why It Prevents Fires)
A clogged dryer vent is a leading cause of house fires. Here's how to clean the full vent line yourself, the warning signs of a blockage, and how often to do it.
This is the rare maintenance task that's genuinely about safety, not just savings. Lint is extremely flammable, and a clogged dryer vent is one of the most common causes of house fires. The good news: cleaning the vent line is cheap, takes under an hour, and you can do it yourself once a year.
Why it matters
Every load sheds lint, and the lint trap only catches part of it. The rest collects in the vent duct between the dryer and the outside wall. As it builds up:
- Airflow drops, so clothes take longer to dry and the dryer overheats.
- Lint accumulates near the heating element — a fire waiting for a spark.
- Energy use climbs as the machine runs longer and hotter.
Clearing the line restores airflow and removes the fire fuel in one go.
Warning signs you're overdue
- Clothes are still damp after a full cycle.
- The dryer or the room gets very hot during a load.
- A burning or musty smell when it runs.
- The exterior vent flap barely moves while the dryer is on.
What you'll need
- A dryer-vent brush kit (flexible rods that extend into the duct)
- A vacuum with a hose attachment
- A screwdriver for the clamp
- Work gloves
Step by step
- Unplug the dryer (and shut off the gas valve if it's a gas model).
- Pull the dryer out and disconnect the vent duct from the back. Have a vacuum ready — lint will spill.
- Vacuum the lint trap housing and the duct opening on the dryer.
- Run the brush through the duct from the dryer end, twisting as you push, working all the way to the exterior vent. Vacuum what you loosen.
- Clean the exterior vent from outside: open or remove the flap cover and brush/vacuum out the lint packed there. Make sure the flap opens and closes freely.
- Reconnect everything, push the dryer back leaving a little slack in the duct (don't crush it), and plug it back in.
- Run a short cycle and check that the exterior flap opens with strong airflow.
A few cautions
- Avoid flexible foil/plastic ducts. Rigid or semi-rigid metal duct is safer and traps less lint. If yours is the ribbed plastic kind, replacing it is a worthwhile upgrade.
- Don't forget the lint trap housing. Deep-cleaning the lint-trap housing a couple times a year catches what the screen misses.
- Keep the run short and straight where possible — every turn collects lint.
Make it a habit
Because the danger is invisible until it isn't, the dryer vent is easy to forget. Build your free Owner Tools and we'll put vent cleaning on your schedule as the critical safety task it is — no login, no address required.