The signs a dryer vent needs cleaning
Drying time is the first sign: the U.S. Fire Administration says that when jeans or towels take a long time to dry, or clothes feel hotter than usual when the cycle ends, a clogged vent is the likely problem.
If your dryer is already running two cycles, the dryer takes too long to dry page has the first checks to make, and our dryer vent cleaning page describes the visit itself. This guide covers the full list of signs, what a cleaning costs in the metro and how often to book one.
Any one of these is a reason to book a cleaning, and two or more together usually mean the run is badly restricted.
- Loads take longer than they used to. Towels and jeans that once dried in a single cycle now need extra time or a second run.
- The clothes and the cabinet run hotter than normal. Heat that cannot leave through the vent stays in the drum and spills into the laundry room.
- The hood flap outside barely moves. With the dryer on, the flap should swing open by itself; one that stays shut or only flutters means little air is getting through.
- Lint shows at the outlet. A gray mat behind the louvers, fuzz stuck to the siding, or a drift of it on the ground below the hood.
- A hot or scorched smell in the laundry room. That one is a reason to stop using the dryer until the run is cleared.
- Moisture where it does not belong. A fogged laundry room window, damp drywall behind the machine, or water pooling in a low spot of the duct.
- Birds at the hood in spring. The USFA report names the nests of small birds as one of the things that block a dryer exhaust.
- Lint showing up in the attic or under the house. It means a joint has come apart or the run ends indoors, which building codes prohibit.
- Nobody remembers the last cleaning. A run left alone for several years is due for a look whether or not the dryer has slowed yet.
A scorched smell, a cabinet you cannot keep a hand on, or a hood flap that stays shut while the drum turns means the dryer waits until the vent is clear. Short of that, follow the USFA’s habits: clean the lint filter before and after every load, and do not leave the dryer running when you go out or go to bed.
Why a clogged dryer vent is a fire question
A clogged vent is a fire question because lint is the fuel, and the U.S. Fire Administration calls it highly combustible.
The USFA’s August 2012 report estimated 2,900 clothes dryer fires in residential buildings a year from 2008 to 2010, with failure to clean the most common contributing factor at 34 percent.
In 28 percent of the dryer fires in that study, the first thing to catch was dust, fiber or lint. The filter traps much of it, but the rest rides out with the moist air, and a full load of wet clothes can hold as much as a gallon and a half of water, so the vent carries a lot of damp, fiber-laden air every time it runs.
The USFA report also found dryer fires rising through fall and winter and peaking in January, at 11 percent of the year’s total. Its authors point to heavier clothing and fewer loads dried outdoors, which is a fair description of a Portland winter, when laundry rarely dries on a line.
Among the report’s examples is a February 2012 fire in a Cornelius home: the owner heard two loud noises from the laundry room, found smoke coming from the dryer, got her children out of the house and then called 911. If a dryer ever smokes, do the same, in that order.
What dryer vent cleaning costs around Portland
Metro dryer vent companies that publish prices list about $100 to $250 for an ordinary cleaning, and national cost guides land in a similar band, with roof vents, nests and packed lint adding to it.
The figures below are ranges as each source published them, read in October 2026, and none of them is a quote for a particular house.
| What the job involves | Range | Source |
|---|---|---|
| A typical cleaning, metro companies that post a price | $100 to $250 | Local company pages, October 2026 |
| A typical cleaning, national | $100 to $200 | Fixr, January 2025 |
| A typical cleaning, national | $102 to $179 | Bob Vila, April 2024 |
| A typical cleaning, national | $186 to $510 | Thumbtack, July 2026 |
| A first-floor vent | $100 to $175 | Fixr |
| A second-floor vent | $125 to $200 | Fixr |
| A roof vent, per vent | $150 to $300 | Fixr |
| Hard-packed buildup | $120 to $250 | Bob Vila |
| Wet, matted lint | $100 to $300 | Bob Vila |
| A bird nest in the vent | $150 to $400 | Fixr and Bob Vila |
| Priced by length | $6 to $11 per foot | Fixr |
The price moves with the length of the run and its bends, whether it ends on a wall or the roof, how it is reached, what is inside it (dry lint, wet paste or a nest), and whether a crushed transition duct gets replaced. Thumbtack’s range runs well above the others, a reminder to ask what each quote covers before comparing them.
Our price board shows a posted starting price for a dryer vent cleaning, with a note on what adds to it, such as a roof termination or a run with many elbows. A chimney sweep visit can take in the dryer vent too, so one appointment covers both.
When you compare quotes, ask whether the price covers everything between the dryer outlet and the hood outside, the hood flap, the transition duct behind the machine and an airflow check at the end. A low number that covers only the hood buys a few feet of cleaning, not the vent.
How often to book a dryer vent cleaning
Book a dryer vent cleaning whenever a sign from the list above appears, and expect a long, bent run in a busy house to need it far sooner than a short wall vent.
The USFA report explains why long runs clog first: when a vent is too long or has many bends, moisture in the warm air condenses on the duct walls and catches lint, which builds into resistance. The report’s own advice is to have the dryer and vent serviced and cleaned periodically, especially once clothes take longer than normal to dry.
Between visits, the lint filter is yours. The same report says to clean it before and after each cycle, to wash it with a nylon brush at least every six months or sooner if it clogs, and to check the duct behind the dryer for crushing or damage.
Rigid metal, semi-rigid and foil: what the duct should be
Smooth-walled rigid metal belongs inside walls, floors and attics, a short semi-rigid metal connector joins the dryer to it, and coiled-wire foil and plastic tubes come out.
| Duct | Where it belongs | Why |
|---|---|---|
| Rigid metal, smooth inside | The run through walls, floors, attics and crawl spaces | Smooth walls give lint little to catch on, and the joints can be sealed and supported |
| Semi-rigid metal | The short connector behind the dryer | It bends to fit without collapsing and stays in view for checks |
| Foil flex with a wire coil | Nowhere in a finished run | Its ridges hold lint, and it sags, twists and crushes flat |
| White vinyl or plastic | Nowhere | Dryer makers say not to use it, and the plastic adds fuel to a fire |
The USFA report says all manufacturers state in their manuals not to use plastic flexible duct between the vent and the dryer, and that even flexible foil vents are not a good choice. Its advice is to replace coiled-wire foil or plastic venting with rigid, non-ribbed metal duct, and to use only a flexible transition listed by UL or another approved testing agency.
Codes, as the same report summarizes them, call for metal duct with a smooth interior, sections supported and sealed together, and a total length limit that shrinks with every bend. The exact figures in Oregon’s residential code and in your dryer’s manual decide whether a particular run is too long.
Roof terminations and runs that end in the wrong place
A vent that exits through the roof costs more to clean and clogs sooner, because the exhaust has to push lint uphill and the roof cap spends a Portland winter under rain, needles and moss.
Runs go to the roof because laundry has moved upstairs. The USFA report notes washers and dryers now turn up in bedrooms, hallways, closets and kitchens, places that need long ducts to reach an outside wall. A roof run is cleaned from both ends, and its cap needs a flap that opens with the dryer and no wire screen, which the report warns collects lint.
Building codes, the report says, require a dryer to exhaust directly outdoors and prohibit venting into attics, soffits, ridge vents or crawl spaces. A run that ends at a soffit grille or stops short in the attic needs a new route rather than a cleaning, and we photograph where it ends before pricing the fix.