How to Clean a Dryer Vent Duct Safely

Cleaning a dryer vent duct removes lint that can restrict airflow, lengthen drying times, and create a fire hazard. Clean the lint screen after every load, but do not treat it as a substitute for cleaning the full duct. Set aside enough time to reach the duct connections and outdoor vent safely. If the duct is inaccessible, damaged, or routed through a difficult space, arrange professional service rather than forcing the job.

What You’ll Need

Dryer-vent cleaning brush with flexible rods, sized for your duct
Vacuum cleaner with a hose and crevice attachment
Screwdriver or nut driver for the duct clamp, if needed
Work gloves and a flashlight
Replacement smooth-wall metal duct and compatible clamps, if the existing duct is damaged or unsuitable
For a gas dryer, the owner’s manual and access to the gas shutoff valve

Use a brush made for dryer vents, not a drill-powered attachment unless its manufacturer explicitly permits it for your duct and you can control the tool. Long, flexible brush rods can twist or break if overdriven. Avoid leaf blowers and improvised tools that can compact lint, damage the duct, or push debris into the dryer.

Step-by-Step

Turn the dryer off and disconnect power. Unplug an electric dryer. For a gas dryer, turn it off, unplug it if the plug is accessible, and close the nearby gas shutoff valve before moving it. If you cannot reach the valve or are unsure how it works, stop and call a qualified technician. Never pull on the gas line or strain the electrical cord.
Make room and inspect the setup. Carefully move the dryer far enough to reach the exhaust connection, without tipping it or dragging it across the floor. Note how the duct is routed and attached. Look for crushed or kinked sections, loose joints, lint buildup, and plastic or foil accordion-style ducting. Dryer exhaust ducts should generally be smooth-walled metal; check the dryer instructions and local requirements before replacing or changing a route.
Disconnect the duct at the dryer. Loosen the clamp or fastener and ease the duct off the exhaust outlet. Do not yank it. If the duct is brittle, crushed, taped in a way that hides damage, or difficult to detach, avoid tearing it; replace it or get professional help. Do not remove the dryer’s cabinet panels to reach lint inside the appliance.
Clean the dryer-side opening. Use the vacuum hose to collect loose lint around the exhaust outlet and the duct opening. Insert the brush gently into the accessible duct, following its route. Rotate or advance it only as directed by the brush maker, and withdraw it slowly so loosened lint comes out rather than being packed farther down the line.
Clean the rest of the duct. Work from the dryer end toward the outdoor termination when the duct layout allows. Add brush rods one at a time, keeping each connection secure. Do not force the brush around sharp bends or push through resistance; a brush can snag, separate, or puncture a duct. Vacuum up debris as it emerges. For a long or sharply routed duct, cleaning from both ends may be necessary.
Clear the exterior vent. Find the outdoor hood or wall cap. Remove lint and debris by hand or with the brush, taking care not to damage the flap, screen, or duct. The flap should move freely and close when the dryer is off. Do not install a fine mesh screen over a dryer exhaust; it can catch lint and restrict airflow. If the outlet is high, roof-mounted, or unsafe to access, leave it to a professional.
Check for a clear, intact route. Use a flashlight to inspect reachable duct sections and connections. Remove all loose lint, but do not try to reach deep into the dryer itself. Replace a crushed, torn, disconnected, or unsuitable duct rather than patching a damaged section with ordinary cloth or duct tape. Keep the route as short and direct as the installation allows, following the appliance manual.
Reconnect and secure the duct. Fit the duct fully over the dryer outlet and secure it with a suitable clamp. Reattach other joints securely, without screws or fasteners protruding into the airflow path where they can catch lint. Make sure the duct is not crushed when you carefully slide the dryer back. Restore the gas valve and power only after the connection is secure.
Run a brief airflow check. Start the dryer and check that air exits the exterior vent and its flap opens. Stop the dryer if you smell gas, hear an unusual sound, see the duct come loose, or notice exhaust leaking indoors. A weak flow after cleaning can indicate a blockage, crushed duct, or appliance problem that needs further inspection.

Common Mistakes

Cleaning only the lint screen: Fine lint can pass the screen and accumulate in the duct and exterior hood.
Using force or a makeshift tool: Aggressive brushing can tear flexible duct, dislodge joints, or leave a brush head stuck inside.
Leaving the duct crushed: Pushing the dryer back too far can undo the cleaning by restricting airflow again.
Using unsuitable duct materials: Thin plastic or foil accordion duct can trap lint and be easily crushed. Use appropriate smooth-wall metal ducting in line with the manual and applicable requirements.
Ignoring the outdoor outlet: A clean indoor section cannot compensate for a blocked hood or stuck flap.
Reaching into the appliance: The drum and cabinet are not the vent duct. Internal appliance cleaning or repair may require a technician.

Tips

Clean the lint screen after each load and check the outdoor airflow periodically.
Clean the duct at least once a year as a general starting point; clean sooner if drying takes longer, airflow weakens, or the duct is long or heavily used. Follow the dryer manual and adjust to what you observe.
Keep the area behind the dryer clear enough that the duct remains open and the appliance can be moved without crushing the connection.
Do not use the dryer if the vent is disconnected or exhaust is blowing into the room. Dryer exhaust should be routed outdoors.
For a condo, shared exhaust, roof outlet, or inaccessible duct, check with building management or a qualified vent-cleaning professional.

Troubleshooting

The brush will not pass through the duct

Stop rather than forcing it. There may be a sharp bend, crushed section, disconnected joint, or obstruction. Try cleaning from the other accessible end only if it is safe; otherwise arrange a professional inspection.

The brush or a rod gets stuck

Do not pull hard or keep turning, which can separate rods or damage the duct. Reverse gently as the tool instructions allow. If it remains stuck, stop and get help before restarting the dryer.

Airflow is still weak after cleaning

Check that the duct is reconnected, not kinked behind the dryer, and that the exterior flap opens. If airflow remains poor, the blockage may be inside an inaccessible run or the dryer may need service. Stop using it if it overheats, smells burnt, or takes unusually long to dry.

The duct is damaged or will not stay attached

Do not run the dryer with a loose or leaking exhaust connection. Replace the damaged section with suitable duct and clamps, or have a qualified technician correct the installation.

You smell gas after moving a gas dryer

Do not operate switches or the dryer. Leave the area and contact your gas utility or emergency services from a safe location. Have a qualified technician check the connection before using the appliance again.

Frequently Asked Questions

How often should I clean a dryer vent duct?

Once a year is a practical general starting point, but the right interval depends on use, duct length, and the dryer manual. Clean sooner if drying times increase or outside airflow drops.

Can I clean the vent without moving the dryer?

Only if you can safely reach the duct connection and clean the full route. Many installations require moving the dryer carefully; do not strain a gas line, cord, or water connection.

Can I use a leaf blower to clear the duct?

A leaf blower can force lint into a blockage, separate duct joints, or damage the vent. A purpose-made dryer-vent brush and vacuum provide more controlled cleaning.

Should dryer vent duct have a screen?

The outdoor termination should not have a fine screen that collects lint. It should have a suitable hood or damper that allows exhaust out and keeps pests and weather from entering, consistent with the appliance instructions and local requirements.

When should I call a professional?

Call one for roof or high-wall outlets, long or inaccessible ducts, recurring blockages, damaged ductwork, a stuck tool, or poor airflow that remains after cleaning. Gas connections and internal dryer repairs also call for qualified service.

Further reading: U.S. Fire Administration. Details can change, so check the official page for anything that matters to you. Spotted a mistake? Tell us. How we write an answer.