An Unseen Risk in Your Home - Dryer Fires
Understanding your dryer vent system, and why it should be regularly maintained.
Many people overlook dryer vent maintenance until a problem develops. This is understandable, since there isn’t wide awareness of the warning signs, which are gradual, and not always visibly apparent.
The primary risk is dryer fires. The National Fire Protection Agency reports that between 2014 and 2018, local fire departments responded to an average of 13,820 home fires in which dryers were involved in the ignition. Most of these fires were caused by lint build-up due to the failure to clean.1
Lint is very flammable, and dryers, whether electric or gas, need a heating element or flame to function. Overheating of a heating element due to a blockage, exposure to flame or a spark from electrical wiring can ignite lint and start a preventable home fire.
There is also the issue of the performance of your dryer. Even the most expensive dryers perform only as well as their ability to vent efficiently. Clogged vent lines increase drying time, sometimes requiring additional cycles which wastes energy and money. Heat and moisture trapped in your dryer adds wear and tear to fabrics, can shorten the life of your dryer, and can lead to the build-up of mold and mildew in your laundry room. Finally, if you have a gas dryer, a clog can cause carbon monoxide to back up into your home.
We’re all familiar with the lint screen in our dryer which should be cleaned-out after each load. But even if you clean the lint screen every time, a good amount of lint (and hair, fur, and paper products) still passes through into your vent line, along with about 1-2 gallons of water vapor per load! The water vapor causes lint to adhere to and cake up on the walls of your vent line.
Dryer vent systems should be inspected, tested, and cleaned annually, or more often, based on your usage profile. Usage factors include the frequency and size of loads run in a household, pets in the household, length of the line and how it is routed.
Dryer vent issues have increased in recent years because homes and lifestyles have changed. In the past, most households had one dryer that backed up to a wall on a ground floor or basement. The vent would run straight out of the house, making it short, efficient, and easier to clean. Today many households have more than one dryer, often with one on a second floor or placed in the middle of the house for convenience. This means long vent lines with lots of twists and turns, making it harder for your system to expel all that lint, moisture, and heat. These systems are more prone to lint build-up and are harder to clean.
Dryer vent cleaning is only part of the larger picture of the dryer vent servicing. Below we review at the components of your dryer vent system that we inspect and service when we come to your home:
Your Dryer
Dryer fires generally start inside dryers and spread to the vent line. The “lint trap”, or the cavity beneath the lint screen, is often clogged with lint, and if your dryer has not vented well over time, the main compartment inside your dryer may also have accumulated lint. We inspect your dryer and clean the lint trap and main compartment as needed to help prevent lint from igniting and spreading into your vent line.
Your Flexible “Transition” Duct
Your “transition” is the flexible duct that connects your dryer to your main vent line. This simple component is the culprit in many poor venting situations. The most common types are semi-rigid aluminum duct, plastic or vinyl duct, or flexible-foil duct.
- Aluminum semi-rigid duct is a good choice but has drawbacks. On the positive side, it is non-flammable and has a smooth interior, but it crumples like aluminum foil when a dryer is pushed too far back against a wall, never regains its shape, and is easily kinked and punctured. Misshapen aluminum semi-rigid invites lint clogs, suppresses air flow, and perforations can expel lint into the area behind your dryer.
- Plastic or vinyl duct is an accordion style flexible duct that should not be used according to current building codes. Simply put, plastic is flammable, attracts lint, and deteriorates over time. The accordion structure also provides more opportunity for lint and moisture to collect. This type of duct should always be replaced.
- Flexible foil duct (slinky foil) is often laminated with plastic, and though it may be rated as “fire resistant”, it can still burn, and has the same undesirable accordion structure as plastic.
We exclusively use a great alternative flexible duct called WizardFlex™, which exceeds code requirements, is non-flammable, has a smooth interior, regains its shape when compressed, and is puncture resistant.
Your Main Vent Line
This is your primary vent line which is routed to a termination point on the outside of your home. Sometimes the line is exposed, or viewable, in an attic, basement, or garage, and sometimes it's hidden inside walls, floors, or ceilings.
The main thing you need to know about a main dryer vent line is that it needs to be rigid metal of a specified thickness, as per IMC and IRC building codes.2
We always inspect your vent cover on the outside of your home to make sure it’s clean, in good working order, and maintains a 4" opening (the same shape and size as your vent pipe). Many vent covers are old and disintegrating, which we can replace. Louvered vent covers are most common. We recommend 3-louvered covers since the types with 4 or more louvers catch more lint, warp, and break more easily. Birds and other pests frequently nest in vent lines. To prevent this, we recommend pest-resistant vent covers. We often see mesh or screens used to deter pests, but this just provides a new place for lint to accumulate and blocks air flow. Pest-resistant vent covers help keep the pests out without obstructing air flow, and do the best job of preventing backdraft air from flowing from the outside into your home. Booster fans are required when the effective length of your vent line reaches 30', but requirements can vary based on your dryer manufacturer’s specifications. A booster fan is installed on your vent line and is triggered when air flow from the dryer starts, boosting air flow to the outside. In the right situations, this is necessary, but booster fans require regular maintenance and cleaning, and are expensive. We stock and install booster fans, but we may also recommend rerouting your line, if possible, to shorten it and eliminate the need for a booster fan. If you haven’t had your vent line inspected in recent memory, you should do so. You vent line should be cleaned annually, or more frequently. But if you experience any of the warning signs below, you should not wait to schedule a professional inspection: Dryer Vent Wizard is a full-service dryer vent company. We not only clean, but repair, reroute and install new dryer vent systems. When we come to your home, we test air flow and inspect every component of your dryer vent system to make sure it complies with building codes, is in good repair, and provides the safest and most efficient way to vent all that heat, moisture, and lint to the exterior of your home. We then speak with you, explain our findings, and provide an itemized proposal before we do any work. We clean your entire vent line using flexible rods with powered rotating brushes that scrub, loosen and remove built-up lint. We clean from inside or outside the home, based on the circumstances. We may also use compressed air with a special nozzle which blasts and pulls out caked-up lint. Compressed air should not be confused with “blowing” out your vent with a vacuum or blower, which is a cheap, fast, and highly ineffective way to clean a dryer vent! No reputable vendor will use this method. Our vans are stocked with all the best materials and tools so we can tackle most every job in one appointment, from inspection to completion. We are fully insured, our techs are all background checked, and we provide our 90-day “Done Right Promise” which promises that we will return to your home to correct any ongoing issues for 90-days. It is our mission help prevent home fires, improve dryer efficiency, and to provide prompt, professional service and great experience for every homeowner. Jim Selden, Owner 1. National Fire Protection Agency Research – Home Dryer Fires, June 2020 2. IMC – International Mechanical Code, 2018; IRC – International Residential Code for One- and Two-Family Dwellings, 2018.Your Vent Cover
Booster Fans
Warning Signs
Our Approach
To schedule your inspection, please call us at: (203) 803-2068.
Dryer Vent Wizard of Norwalk
- Serving Fairfield County -
