Your dryer vent probably needs cleaning if clothes take longer than normal to dry, the dryer or laundry room gets hot, or little air comes out of the outside hood. Do not wait for all the signs. One of them is enough reason to check.
What are the signs of a clogged dryer vent?
- Clothes are still damp after a normal cycle, or you need a second cycle.
- The dryer feels very hot on top, or the clothes come out hot.
- The laundry room feels warm or humid while the dryer runs.
- You smell something burning or a musty odor.
- Lint is collecting around the lint filter door, behind the dryer, or around the outside hood.
- The flap on the outside hood barely moves, or you feel weak airflow when the dryer is on.
- You see a bird nest or debris at the outside opening.
- The dryer shuts off before the cycle ends.
The NFPA advises checking that the exhaust pipe is not restricted and that the outdoor flap opens when the dryer runs. It says to clean the vent once a year, or more often if drying takes longer than normal. The U.S. Fire Administration adds that blockages can also come from nests of small birds or other animals, or from damage to the vent itself.
A clean dryer vent matters
A dryer moves hot, moist air through a pipe. When that pipe is full of lint, the air has nowhere to go. Heat and moisture stay in the dryer and the pipe.
A yearly cleaning removes the lint fire hazard. It also brings everyday benefits:
- Faster drying.
- Lower energy use, because the dryer runs for less time.
Here are the facts from NFPA. It estimates that local fire departments responded to an average of 13,820 home fires per year in 2014 to 2018 in which a dryer was involved in ignition. Failure to clean was the leading factor.
| Factor contributing to ignition | Share of home dryer fires, 2014 to 2018 |
|---|---|
| Failure to clean | 32% |
| Mechanical failure or malfunction | 27% |
| Electrical failure or malfunction | 16% |
NFPA says this appears to be mainly lint build-up, because 27 percent of dryer fires started when dust, fiber, or lint ignited. Its definition of “home” includes apartments, so these figures cover condos too.
Lint builds up even when you clean the filter
The filter does not catch everything. The U.S. Fire Administration says that much of the lint is trapped by the filter, but lint is also carried through the vent system along with moist air. A full load of wet clothes can hold as much as one and a half gallons of water, so a lot of damp air has to leave through that pipe. Every bend, joint, or dent gives lint a place to catch and grow into a blockage.
A yearly dryer vent cleaning is a good rule
Once a year is a good rule, and it is what we recommend. NFPA gives the same guidance: once a year, or more often if drying takes longer than normal.
Some South Florida homes need more attention than average:
- Long or rooftop vents. Some vents run through the attic or up to the roof. A long run has more places for lint to settle.
- Coastal air. Near the coast, salt air can be hard on metal hoods and flaps. Check that the flap moves freely.
- Condos and towers. Vents in tall buildings can be very long. See our guide to dryer vents in condos and high-rises.
Checking the vent yourself
You can do a basic check. A full cleaning of a long or hidden vent is a job for a trained technician.
- Clean the lint filter, and remove lint from around the filter slot.
- Run the dryer on an air-only or low-heat setting and go outside to the vent hood.
- Check that the flap opens fully and that you feel steady airflow.
- Look for lint, a nest, or debris at the opening. Do not put your hand inside.
- Look at the pipe behind the dryer. NFPA advises rigid or flexible metal venting. The U.S. Fire Administration notes that plastic or vinyl exhaust materials can cause problems.
- If the airflow is weak, the pipe is crushed, or you cannot reach the vent, schedule a cleaning. If you have a gas dryer, have a qualified professional inspect the gas line and connection.
Steps in a professional dryer vent cleaning
- A technician inspects the vent run.
- The vent is cleaned along its full length, which removes the lint fire hazard.
- The outside hood and flap are checked.
- Airflow is confirmed afterward.
At Blue Pelican, every visit starts with a free Whole-Home Air & Attic Check. The technician confirms the price, you approve it, and nothing is added without your approval. We show you the result, with photos whenever possible. Our technicians are our own employees, never subcontractors.
See the details on our dryer vent cleaning page, or book your free Whole-Home Air & Attic Check.
Sources
- NFPA, “Home Dryer Fires,” Marty Ahrens, June 2020 (13,820 fires per year, 2014 to 2018; failure to clean 32%; lint 27%; mechanical 27%; electrical 16%; definition of home): https://content.nfpa.org/-/media/Project/Storefront/Catalog/Files/Research/NFPA-Research/US-Fire-Problem/osdryer.pdf
- NFPA, “Clothes Dryer Safety” tip sheet (clean the vent once a year or more often; metal venting; outdoor flap; leading cause is failure to clean): https://www.nfpa.org/-/media/project/storefront/catalog/files/safety-tip-sheets/dryersafetytips.pdf
- U.S. Fire Administration, “Clothes Dryer Fires in Residential Buildings (2008 to 2010)” (lint carried through the vent; nests; plastic or vinyl exhaust materials): https://www.usfa.fema.gov/downloads/pdf/statistics/v13i7.pdf
