Preventing Dryer Vent Fires

Posted by Van Purser on Tuesday, February 1st, 2011 at 10:12am.

Excessive built up lint inside clothes dryer cabinets and vents causes more than 15,000 fires every year, with an estimated 97 million dollars in property loss. Considering the stakes involved and the frequency of residential dryer fires, the topic of dryer venting deserves more attention than it gets.

What causes lint fires? 

Lack of maintenance is the leading cause of dryer fires.  Clothes dryers must vent hot air to the outside of the home. If lint builds up in the dryer vent or inside and around the dryer cabinet, it can block the flow of air causing the dryer to perform poorly, raising the operating temperature of the dryer and causing over heating. The lint can be ignited by electric heating elements, gas burners or even a spark from the motor, and the flames then travel through the lint lined exhaust vent pipe.

Additionally placing combustible or improper materials in the dryer, such as clothes that are soiled with volatile chemicals or items like foam-backed rugs and athletic shoes can also contribute to dryer fires.   Also insufficient air flow resulting from improper installation or blocked exhaust vent pipe can contribute to dryer fires.

What can you do to help prevent dryer fires?

  • Clean the lint screen / filter before or after drying each load of clothes.  If clothing is still damp at the end of a typical drying cycle or drying requires longer times than normal this may be a sign that the screen or the exhaust duct is blocked.
  • Clean the dryer vent and exhaust duct periodically.  Check the outside dryer vent while the dryer is operating to make sure exhaust is escaping. If it is not, the vent or the exhaust vent pipe may be blocked.  Cleaning may be accomplished by applying forced air at vent and dryer connection and blowing the duct clean. Additionally a qualified service person clean the interior of the duct with a brush, provide it is a solid pipe duct.
  • Clean behind the dryer, where lint can build up.  Have a qualified service person clean the interior of the dryer chassis periodically to minimize the amount of lint accumulation.  Keep the area around the dryer clean and free of clutter.
  • Take special care when drying clothes that have been soiled with volatile chemicals, such as gasoline, cooking oils, cleaning agents, or finishing oils and stains.
  • Replace plastic or foil, accordion type ducting material with a rigid or corrugated semi-rigid metal duct.  Most manufactures specify the use of a rigid or corrugated semi-rigid metal duct, which provides maximum airflow.  The flexible plastic or foil type duct can more easily trap lint and is more susceptible to kinks or crushing, which can greatly reduce the airflow.
  • Turn the dryer off when leaving home.  Do not leave the dryer running if you go out because if it malfunctions no one will be there to stop a possible disaster. 

View YOU TUBE video on Dryer Ventsdryer_vent_1_150

There is a new product that monitors dryer lint build-up called Lint Alert.  Lint Alert is a home safety device that monitors and displays the back pressure levels found in the exhaust conduit of the dryer.  Pressure levels found in the dryer duct typically increase over time due to lint build-up, animal nests or vent hoods that become inoperable. 

The Lint Alert features a digital pressure sensor coupled with a programmable integrated circuit.  The device can determine if your dryer is on, and what levels of pressure exist.  When the pressure reaches an unsafe level the alarm will activate, indicating maintenance if is required.  The alarm state is displayed as:  LED light bar flashes on and off alternating with blue logo, with buzzer beeping.  Prior to the alarm state, a slow progression of the LED Blockage Indicator will display fractional buildup. 


Steve Sheffield is a full time home inspector with certifications through ASHI, American Society of Home Inspectors, and the IRC, International Residential Building Code.  He has completed over 1500 inspections since starting Hometown Inspection Services, LLC eight years ago.  Prior to starting Hometown Inspection he was in the lumber / construction supply business for over 30 years. He can be reached at: 
steve@hometowninspection.com or 770-789-1463.



Van Purser and his wife Jeanne are a licensed Real Estate Brokers in Georgia.  Since1984 they successfully purchased and renovated over 400 homes.  Their expertise is in representing Buyers or Sellers as an advocate; which means always ensuring their best interest.  Additionally, they represented hundreds of clients over the years as an Associate Broker with Metro Brokers, RE/Max and now with his own firm.  He and his wife, Jeanne, have been married since 1977.   Van or Jeanne can be reached at 770-623-3313, or by email at vanpurser@vanpurser.com or jeanne@vanpurser.com

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