Dryer Vent Cleaning and Fire Prevention: What Every Homeowner Should Know

Cleaning the lint trap feels like doing your duty, right? It’s at the end of the load, and you
pull the screen out to peel away the gray mat of fuzz and tossed it out. Not a problem,
right? It’s true the lint trap catches a good deal of the lint, but it doesn’t catch it all. The
rest makes its way into the dryer vent.

Dryer vents are there to remove the hot and moist air that’s produced while drying
clothes, and it empties that to the outside of the home. Over the course of a year, if not
more, the dryer vent collects lint, and it traps heat and restricts air flow.

The National Fire Protection Association stated that thousands of home fires occur
yearly, and the main cause was clogged and dirty dryers. A good part of these fires
could have been prevented if the consumer was more aware.

The purpose of this guide is to cover the basics of dryer vent fire hazards, spotting signs
that your dryer vent is a hazard, how to safely clean your dryer vent, and when it’s
appropriate to call in the professionals. It’s the goal of this guide to help the consumer
provide a safer environment for their family and home.

Why a Clogged Dryer Vent Is a Real Fire Risk

Most people are aware that leaving the iron on, or a lit candle unattended can start a
fire, but few people have a clear understanding about how their dryer can be a fire risk.

Understanding how your dryer works is the first step in understanding the danger. A
dryer works by heating air, tumbling your clothes through it, and pushing the moist air
out through a vent. That cycle depends on one thing above all else, air flow.

Lint is composed of tiny fibers of cotton, wool, and polyester and other fibers you wash.
Being light weight, dry, and extremely flammable, lint is an excellent fire starter. As lint
clogs a dryer vent, two things happen at the same time.

First, the air flow through the vent lessens and the hot air in the dryer builds up. Second,
the lint becomes a fire hazard. It is possible for the dryer to catch on fire, with no one
aware of the danger because of the extreme temperatures caused by restricted air flow.

Some homeowners believe that as long as the lint trap is cleaned after every load of
laundry, the dryer is safe, but fibers collect in the duct work, especially at joints, bends,
and the exit point of the duct where it meets the wall.

Many things can contribute to an increased fire risk, clogged dryer vents are only one of
those things. It is much safer to assume that everything can be a fire risk, and to take
proactive measures against it.

Fire safety organizations have tracked this problem for several years, and the data
show dryers account for the largest percentage of residential fires caused by laundry
equipment, and by far the most prevalent cause for this type of fire is lack of
maintenance. Fires related to home dryers tend to increase during the fall and winter
months, because of the increased use of laundry equipment and larger loads, such as
towels and blankets. Furthermore, during the colder months, homes tend to be shut-up
tighter, thus concentrating the contaminants and pollutants inside.

Blockage of a dryer vent can create several health and safety hazards for a home.
Restricted airflow through a dryer vent can damage the dryer, increase energy costs,
and create a dangerous situation in which a buildup of moisture occurs in the duct
and/or a carbon monoxide backflow occurs in a home. Improper venting creates a fire
hazard and carbon monoxide safety issue.

Signs Your Dryer Vent Needs Cleaning

There are several warning signs to look for to help you identify an obstruction in your
dryer vent. The warning signs often are attributed to normal wear and tear on an
appliance, but each can be an indication of restricted air flow.

Perhaps the most common, and most easily ignored sign, is that clothes do not fully dry.
If your dryer is no longer drying clothes like it used to, the vent probably is the problem
before the dryer itself.

Clothes come out smelling musty or moldy. Moisture in the dryer cannot completely
evaporate, so it condenses on the inside of the drum and trapped air in fabric.

The outside of the dryer gets hot to the touch. Top and side portions of a dryer get
warm during a drying cycle. If the outside of the dryer gets hot to the touch, then the
dryer is having trouble venting moisture.

The laundry room gets humid. Extra moisture in the room can mean that there is a
blockage or leak in the exhaust vent. This can also let condensation collect on windows
and cause lint to float in the air.

The flap over the vent outside doesn’t move. A blockage or leak in the vent can
restrict air from escaping. If this happens, the flap will not move. Go outside and check
while the dryer is running.

You smell a burning odor. A blockage in the exhaust can cause a build up of fibers
that can burn, causing a strong odor. A strong odor means that the dryer should not be
used until it is checked.

There is lint blocking the vent. The exhaust should clear lint and fibers. If it doesn’t,
lint can collect around the dryer and block the exhaust hood on the outside of the
building.

You should have your dryer vents cleaned as soon as you see any of the signs below. If
you put it off you could have a larger problem on your hands.

The best way to clean your dryer vents safely is…

Cleaning your dryer vents can cost a good deal of money if you hire a professional to do
it, and it is not hard to do yourself. Here is the basic idea behind the process.

What you will need

A dryer vent cleaning kit which usually contains some flexible steel rods that you can
buy at your local hardware store.

● A vacuum
● A screwdriver
● Foil tape to repair the joints (not duct tape)
● Safety gloves and a dust mask

Step-by-Step Process

1. Safety first! Close the gas supply valve and unplug your dryer.
2. Move your dryer away from the wall and pull it out enough that you can work
behind it.
3. Loosen the clamp and remove the duct from the back of the dryer. Do the same
at the wall connection if you can.
4. Clean the larger pieces of lint from the duct and your dryer with your gloved
hands or the vacuum.
5. Use the brush and rod kit. Attach the brush to the drill (or hand the brush to the
rod and push it along). Push it through the duct from the inside, adding rod
sections as you go. If you can, work from the outside as well, and proceed from
the dryer end. Use the drill to loosen compacted lint, then pull it out and vacuum
the duct.

6. Clean the vent hood exterior. Take a look at the exterior of the cap and remove
any build up. Check that the vent hood flap functions properly and has no
blockages. Lint is not the only thing that gets trapped in a vent.
7. Clean lint trap housing. Remove the lint screen and vacuum the frame it sits in as
well as the area beyond it. Lint often hides deep within this area.
8. Reattach the duct. Refasten the clamps and seal with foil tape. Make sure the
duct isn’t crushed when you push the dryer back into place.
9. Run a test cycle. Set the dryer to a short, high heat cycle, and check the exterior
vent. You should feel air being forced out through the vent.

Choose the Right Duct Material

When you have your vent exposed, check the ductwork. Not all duct material is created
equal. Flexible white vinyl or thin foil accordion style tubing is very common but is not
ideal. It collects lint, sags, and can ignite. Building code officials and safety experts
recommend smooth wall, rigid or semi-rigid metal ductwork for the reason that lint can
pass through and collects less, thus there is less of a fire hazard. Replacing plastic or
poor condition ductwork is one of the best fire prevention upgrades.

How Often Should You Clean?

Cleaning at least once a year is a good target. However, if you have a large household,
lots of laundry, shedding pets, or a long vent run, target cleaning every 6 months. And if
you have a large family and do a lot of laundry with bulky items (bedding and towels),
and/or live in a house with a long, winding, or bending vent run, you should clean it
more frequently. No matter what, make sure you always clean the lint trap!

When to Call a Professional?

Knowing when to call a professional for a vent cleaning is part of being a good
homeowner. Cleaning a long vent run that goes through multiple floors and/or a roof is
very difficult. If a basic cleaning of the vent run leaves material in the hard to reach
areas, it can collect and cause a fire hazard.

Call a pro if you can’t get lint build-up to dry after multiple attempts, if you see signs of
scorching or if there is melted material in the duct, if the runs are through walls or
ceilings that you can’t access, or if you are simply not comfortable doing the work.

What to Expect From a Professional

A good dryer vent cleaning service will use a brush system and vacuum to clear the
entire length of the duct and check for damage. They will also check the installation of
the vent, check airflow, and clean the exhaust hood.

When choosing a company, look for positive reviews and be aware of pricing.
Technicians should be certified and the company should be insured. The company
should provide before and after pictures or readings to show improvement. Be
suspicious of prices that seem too low or of a company that can’t explain their process.

Professional dryer vent cleanings cost less than a repair or new appliance, and are a
small fraction of the cost of a house fire. They are a good investment.

The Best Habits to Keep Your Dryer Safe

An scheduled vent cleaning is a great first step, but there are simple habits that can
help ensure the safety of your dryer as well.

The dryer can be dangerous and cause a fire if not used properly. Never run the dryer
when you are not at home or when you are sleeping. If there is a fire, you want to make
sure that you are alert and near enough to the dryer to be able to put the fire out.

Do not overload the dryer. Overloading the dryer blocks the airflow and makes the
dryer work harder.

Emptily the lint trap after every use. This takes only a few seconds and helps to
prevent dryer fires.

Do not keep flammable items near the dryer. Items may catch on fire and start a
house fire.

Do not put items in the dryer that are not meant to be dried. Clothes that have
flammable stains or chemicals can ignite on their own and cause a fire.

Check the dryer vent from the outside. This will help see blockages early.

Install smoke alarms and carbon monoxide detectors. Put them near the laundry
area and test them regularly. They are a second line of defense in case a fire starts.

Cloth fabric softener sheets and dryer sprays can build up on the lint screen and block
airflow. Make sure to clean the lint screen with warm soapy water a few times a year
and allow it to fully dry before use.

Common Myths About Dryer Vent Safety
There are a few common misconceptions that keep people from looking into dryer vent
safety. Here are the answers to those myths.

"My lint trap is clean so I'm good." As mentioned earlier, the lint trap does not catch
everything. The duct still needs to be cleaned.

"I just bought a new dryer, I'm good." The dryer is not the only thing that can catch on
fire. The house ventilation system is part of the house and can still be long, kinked, and
blocked regardless of how new the dryer is.

"I would know if something were wrong." You can get used to longer drying times. You
may not notice the build up of lint.

"Old, neglected houses are the only ones that catch on fire." Dryer fires happen to all
types of houses. Dryer fires happen because of a lack of maintenance.

Conclusion: Your Dryer Vent is a Hazard, Take Small Steps Now to Protect
Everything You Love

The dryer vent is something people tend to forget because it is behind the scenes. The
dryer vent can affect the safety of your house more than almost any other system. A
buildup of lint can make an otherwise safe system a fire hazard.

Prevention is relatively simple. Make sure to clean the lint trap after every load. Be
aware of the warning signs. These can include longer drying times, musty or smelled
clothes, and weak airflow from the exterior vent. The dryer duct can be clogged as well
and should be cleaned at least once a year. You can also hire a professional to clean it
as well. Using rigid metal ducts can help as well as keeping the area surrounding the
dryer clean. You should also never leave the dryer on when you are not at home.

Article provided by Katherine Langford