Key points
- Every load sends gallons of water out the dryer vent as warm, moist air.
- A disconnected, crushed or kinked vent releases that moisture indoors.
- Vents that end in an attic or crawlspace cause condensation and mold there.
- Lint buildup is also a fire hazard.
Warning signs
- Laundry room feels humid or windows fog during drying
- Clothes take longer than usual to dry
- Lint around the dryer or on the floor behind it
- Musty smell or dark spots on walls or ceiling near the laundry
Fixes
- Vent to the outside — never into an attic, crawlspace or garage
- Use rigid or semi-rigid metal duct, kept as short and straight as possible
- Check the outside flap opens and is not blocked
- Clean lint from the duct regularly
If mold is already there
Small areas can sometimes be cleaned — see when DIY mold cleanup is OK. Larger growth, or growth in an attic or crawlspace, should be assessed. Mold inspections start at $99. See mold in attics and front-load washer mold smell.
Common questions
How often should a dryer vent be cleaned?
Clean the lint screen after every load. Check and clean the duct itself at least once a year, and more often with a long vent run or heavy use. Follow the dryer manufacturer’s instructions for the duct material and maximum length.
Can I vent a dryer indoors?
Gas dryers must always vent outside because the exhaust carries combustion gases. Indoor lint kits sold for electric dryers put all of the moisture from each load into the house, which is exactly what feeds condensation and mold. Venting to the outdoors is the fix.
Why is there water in my dryer duct in winter?
Warm, moist exhaust cools as it travels through a cold duct in an unheated attic, garage or crawlspace, and the moisture condenses inside the pipe. Keep the run short and straight, insulate duct that passes through unheated space, and make sure the outside flap opens freely so moist air is not trapped.
Mold near the laundry?
Call (385) 250-2825 — answered live 24/7 by the Vault crew.
Found mold in a Provo home? Start with a mold inspection, then see how we handle mold remediation in Provo. Call (385) 250-2825.