Most people clean the lint screen and stop there. It feels like enough — the screen is full every time, after all. But the lint you see is only part of what your dryer produces, and the rest ends up in a place you rarely look: the duct that carries hot, damp air outside.
Where the lint goes
Every load of laundry sheds fibres. The lint screen catches most of them, but a fraction always slips through and is blown into the exhaust duct. Over months, that lint sticks to the inside walls, especially where the duct bends, sags or meets the outside vent cap. Each layer narrows the path a little more.
A dryer works by pushing hot air through wet clothes and blowing the moist air outside. When the exit is partly blocked, that air can't leave fast enough. The clothes stay damp, the cycle runs longer, and the inside of the machine gets hotter than it was designed for.
What it costs you before anything catches fire
- Time and energy. Loads that once took 45 minutes stretch to 70 or 90. You pay for that electricity or gas every time.
- Wear and tear. Thermal fuses, heating elements and belts fail more often in an overheating dryer — a common reason for repair calls.
- Moisture. If a duct is crushed or disconnected, warm, damp air can leak into walls or the laundry room and cause mould.
The fire risk is real
Lint is essentially dry, fluffy fuel. According to the US Fire Administration, an estimated 2,900 home clothes dryer fires are reported each year, causing deaths, injuries and around $35 million in property loss, and failure to clean is the leading factor contributing to them. The danger is highest with older white plastic or thin foil ducts, which trap more lint and can melt or burn.
How often to clean — and how
Clean the lint filter before or after every load, and wash it with warm soapy water every few months if you use dryer sheets, which can leave a film that blocks airflow. Clean the entire vent duct at least once a year, and more often for large families, pets or long duct runs.
For a short, accessible duct, a dryer-vent brush kit and a vacuum do the job: unplug the dryer, pull it away from the wall, disconnect the duct, brush and vacuum it from both ends, and clear the outside flap. Long runs through walls or roofs, or ducts with several bends, are best left to a professional dryer-vent cleaner.
Upgrade the duct if you can
Safety agencies recommend rigid or semi-rigid metal ducts that are as short and straight as possible. If yours is white plastic or a crumpled foil hose, replacing it is a cheap upgrade that reduces both clogs and fire risk.
