Dryer Vent Fire Warning Signs

Next steps (at a glance)

If you only do 3 things:

  1. Check how long clothes take to dry.

  2. Look behind the dryer for lint buildup or crushed venting.

  3. Clean the vent path if airflow seems weak—or schedule a cleaning.

Urgency level: Medium
(Becomes High if drying times suddenly increase, the dryer overheats, or you smell burning.)

Short answer

Dryer vent fires usually start when lint buildup restricts airflow, causing heat to rise inside the dryer or vent. The warning signs often appear weeks or months before a fire risk becomes serious.

Longer drying times are the most common early clue.

Why dryer vents matter

Dryers move hot, moist air out of the home through a vent. When lint accumulates, that air can’t escape efficiently. Heat builds up, and lint is highly flammable.

This is why dryer vents—not the dryer itself—are a common fire source.

Common causes of dryer vent fires

  • Lint buildup in the vent or duct

  • Crushed or kinked vent hose

  • Long or poorly routed vent paths

  • Plastic or foil venting (instead of rigid metal)

  • Infrequent cleaning

Lint traps catch only part of the lint. The rest moves into the vent.

Warning signs to take seriously

  • Clothes take longer than normal to dry

  • Dryer feels unusually hot to the touch

  • Laundry room becomes very warm or humid

  • Burning or musty smells during operation

  • Lint visible behind or beneath the dryer

  • Exterior vent flap doesn’t open fully

Any combination of these increases risk.

What happens if vent issues are ignored

  • Overheating inside the dryer

  • Damage to heating components

  • Increased fire risk inside walls or ceilings

  • Higher energy use and wear on the dryer

Dryer vent problems usually worsen gradually, not suddenly.

DIY-safe checks you can do

These checks are generally safe for homeowners:

  • Clean the lint trap before every load

  • Pull the dryer slightly away from the wall and look for crushed venting

  • Check the exterior vent flap while the dryer runs

  • Vacuum visible lint around the dryer area

Do not disassemble the dryer or reach deep into wall vents.

Maintenance that actually helps

  • Lint trap cleaning every load reduces immediate buildup

  • Visual vent check every few months catches crushed hoses

  • Periodic vent cleaning keeps airflow strong

  • Short, straight vent paths reduce lint accumulation

Good airflow keeps temperatures down.

If you don’t want to call a professional yet but want to stay safe

Prioritize these:

  • Reduce drying loads if drying times increase

  • Clear visible lint immediately

  • Stop using the dryer if overheating or burning smells occur

If airflow doesn’t improve after basic cleaning, professional vent cleaning is the safest next step.

Common mistakes

  • Assuming the lint trap prevents vent buildup

  • Ignoring longer drying times

  • Using plastic or foil vent hoses

  • Pushing the dryer tightly against the wall

Dryer efficiency and safety depend on airflow.

When to call a professional

Contact a professional if:

  • Drying times continue to increase

  • The dryer overheats or shuts off

  • The vent path runs through walls or ceilings

  • You haven’t cleaned the vent in years

What to ask:

  • Full vent path cleaning

  • Vent material and routing assessment

What to expect:
Professional cleaning removes built-up lint from the entire vent run. Costs vary by vent length and access.

Related guides

Disclaimer:
This is general information only. When in doubt, hire a licensed professional.