Dryer Exhaust Vent Cleaning

Why Now?

Historically, clothes dryers were located a short distance from an outside wall. Their short, straight exhaust vent runs worked well, leaving little need for maintenance and making inspecting easy.

Today, I find laundry rooms located practically anywhere in the home. It’s commonplace to find the dryer installed on an upper level with a long, concealed run including several elbows, often resulting in slowed and restrictive airflow. Given the tightness of modern homes, proper handling of dryer exhaust has become even more critical than it was in older homes that breathed.

Problem Conditions

Most often, the dryer is pushed as close to a wall as possible, with a crushed or kinked transition duct, which immediately slows the flow of air and creates a trap for lint to collect. The transition duct should not exceed eight feet in length, should be of UL-approved material (not plastic), limited to a single length, and not have any part concealed within construction. Periscope-type connectors (sometimes called Banjos) eliminate the common problem of kinked and crushed transition ducts behind the dryer. Metal foil tape should be used on the ends of the periscope to seal any cracks. Air leakage disrupts the efficient flow of air.

Dryer exhaust vents in many homes tend to sag because they are not guided through the rafters or otherwise properly supported, make sharp turns or roller coaster up and down. This creates turbulence, preventing all the moisture and lint from blowing out. The common spiral-ribbed flexible vents by mere design create turbulence and reduce airflow. All too often, the termination sleeve on this type of vent gets bent inward when it’s installed, creating a dam for lint to snag. Some older termination hoods are restrictive by design, not allowing the damper to fully open. These common conditions, as well as exceeding recommended lengths and failing to perform routine maintenance, all increase the potential for lint becoming trapped within the vent system, leading to blockage.

What’s Being Done To Help Reduce Dryer Fire Risks?

The slow elimination of dangerous dryer exhausting products from the market over the last two decades has been the most significant step toward reducing fires. Years ago, the standard dryer vent was a white vinyl spiral wire vent. Not only was the vinyl susceptible to overheating and melting, the spiral “ribbed” construction created turbulence, reducing airflow, leading to lint accumulations within the ribs.

A Mylar-covered spiral wire vent replaced the white vinyl vent. Mylar is a shiny metallic-coated polyester film (often called foil), and it is slightly more heat-resistant than vinyl, but still presents potential problems for many of the same reasons.

The use of metal exhaust vents is now the widely accepted standard, recommended and/or required by Underwriters Laboratory (UL), the Association of Home Appliance Manufacturers, the Consumer Product Safety Commission, most (if not all) dryer manufacturers and most building codes. The use of an all-metal (rigid or semi-rigid) dryer exhaust vent helps to achieve optimal airflow, reducing lint buildup and reducing the operating temperatures of the dryer.

Warning Signs!

bullet Clothes take an unusually long time to dry.
bullet Clothes are hotter than usual at the end of the cycle.
bullet Outside of dryer is unusually hot.
bullet Damper (or flappers) on exhaust termination doesn’t open or barely opens when dryer is on.
bullet Laundry room feels warmer or more humid than normal.
bullet Unexplained moisture stains appear in concealed dryer exhaust vent area.
bullet Burnt smells in laundry room.

Current Industry Standards

Industry standards provide an example of what can be done to reduce the potential hazards associated with the exhaust from clothes dryers.
The dryer exhaust system must be independent of all other systems and convey the moisture and any products of combustion to the outside of the home. The vent must not exhaust to attics, crawl spaces, basements, chimneys, the cavity of any wall or any interior room.
Dryer vent must be at least 4 inches in diameter or at least the size of the dryer outlet. The exhaust vent must not extend into or through (HVAC) vents or plenums. The exhaust vent system should be supported and secured.
The maximum length for a clothes dryer exhaust vent should not exceed 25 feet. This length should be decreased by 2.5 feet for every 45-degree bend the vent makes, and 5 feet for every 90-degree bend the vent makes. This does not include the transition duct.
The dryer exhaust vent should be constructed of rigid metal (aluminum or galvanized steel). The interior of the vent should be smooth surfaced with the joints running in the direction of the airflow. There should be no sheet-metal screws, rivets or any other fastener used to connect the vent joints. Fasteners that extend into the airway will catch lint and obstruct airflow. Clamps or foil duct tape should be used to secure joints.
Outside termination must be equipped with a back draft damper, which prevents moisture/air intrusion and the entry of small animals. The termination must not have a screen covering the exhaust outlet.


Clothes dryer exhaust vents should always be installed in accordance with the manufacturer’s instructions. If the make and model of the dryer is known, the manufacturer’s instructions override the standards. This is true even if the manufacturer’s instructions are more lenient, which they often are. Some allowing the length of the vent to exceed the standard by as much as three times the standard’s 25-foot maximum. Manufacturer’s instructions may specify avoiding 90-degree turns, or approve semi-rigid duct, while specifying it should be fully extended. Instructions may specify that semi-rigid cannot be used in concealed areas, or that clamps must be used at joints without tape, or they may specify tape or clamps. At least one specifies that vents in unconditioned spaces should be insulated.
When the manufacturer is unknown or the instructions are unavailable, industry standards and good practices provide guidance on how exhaust systems should be configured.

Good Practice

If possible, rigid aluminum or rigid galvanized steel duct should be used (especially if concealed). If flexible metal duct must be used, use the semi-rigid type.
The dryer vent should be as straight and short as possible. Minimize 90-degree turns. Sharp turns cause back pressure and create resistance to airflow. Two 45-degree bends are more efficient than one 90-degree bend. For best performance, separate all turns by 4 feet of straight vent. Duct joints should be wrapped with foil tape to make air and moisture tight. Avoid the gray duct tape as it will deteriorate over time.
The hood should have at least 12 inches of clearance between the bottom of the hood and the ground or other obstruction. The hood opening should point down.
Ducts should always have adequate support, especially at each joint.
A dryer vent should never exhaust near the fresh air intake of a high-efficiency furnace, water heater or any (HVAC) intake.
Rigid seamed exhaust vent ideally should be installed with the seams up to prevent any accumulation of condensation from seeping out. When possible, horizontal runs of dryer vents should slope slightly downward (1/4 inch per foot) toward the exterior termination to reduce the possibility of condensation accumulating and collecting lint.
In cold climates, insulating the dryer exhaust vent in unheated spaces may help to limit the condensation from forming inside the vent and collecting lint. Note: At least one dryer manufacturer specifies this in its installation instructions.
Exhausting a dryer near or next to an air conditioning or heat pump condensing unit should be avoided. The expelled lint can collect and clog the condenser fins and will likely require continual condenser cleaning.

Be Aware

The common Mylar (foil) and white plastic spiral flexible vents contribute to poor dryer performance. These spiral ducts are no longer recommended and will void the warranty of most (if not all) dryers, if used.
The use of PVC pipe is not recommended, and is against all standards and specifications. As the lint, air and moisture passes through the PVC it staticly charges and will increase the buildup of lint.
Magnetic dampers on exhaust hoods are restrictive and should not be used on dryer exhaust systems.
Venting up or through the roof, although possible, should be the next to last choice. These systems clog up faster and demand close monitoring and routine cleaning for safety and efficiency “Fighting Gravity”.
Venting under the slab of the home, although possible, should be the very last choice. These systems clog up faster and demand close monitoring and routine cleaning for safety and efficiency. It is extremely difficult for the moister and lint to vent from routining this way and I have routinely removed over 2 gallons of water from systems that were routed this way.
Dryer exhausting through the roof should be ducted to a special dryer roof vent without screen. The roof vent or louvered plenum must be equivalent to a 4 inch wall termination in regard to resistance to airflow and back-flow prevention, and should require little or no maintenance to prevent clogging.
The older dryer exhaust hood terminations have a 2- 1/2 inch hood opening that is restrictive by design often clogging and sticking open. The newer versions have a full 4 inch hood opening or a series of flappers allowing unrestrictive exhausting and improved performance.
Mobile home exhaust vents must be secured to the home and should not discharge under the home.
Clothes dryers require make-up air; if the laundry area is too tight, it will affect the operation and function of the dryer exhausting. In addition, dryers operating in utility areas with gas appliances that lack sufficient make-up air can create a dangerous back-drafting (CO) problem.

What About Vent Buckets Or Lint Traps?

Sold in hardware stores everywhere, a vent bucket (aka lint trap) is a device that you fill with water, connect to a clothes dryer vent and hope the water collects the lint. Although widely used, especially in older homes, they are not recommended. They have a limited ability to catch lint, while allowing gallons of water to be pumped into the home and create a potential air quality issue. Whether it will have a negative effect depends on a number of factors such as the climate, how often the dryer is used, and so forth. Another popular home remedy is to use a woman’s nylon stocking to filter lint, also not recommended; it creates a fire hazard!

Dryer Exhaust Boosters

Booster fans can be used to exceed the maximum 25 feet or to help with vertical applications. The recommended location of a booster fan is a minimum of 15 feet from the dryer outlet. If mounted closer, it may create enough pressure to lift or pull wet lint into the fan impeller, resulting in excessive lint loading in the fan. The best location for mounting the fan is as close as possible to where the vent terminates. (Exception: If a secondary lint filter is installed between the dryer and the booster fan, the mounting location can be within the 15-foot minimum distance.) The fan must be mounted securely and must be accessible to perform recommended maintenance. If the fan is not readily accessible from the dryer room, it is recommended that a permanent label be placed near the dryer transition duct stating that a remote booster fan is used. A pressure switch activates a booster fan automatically, and the fan cycles on and off in 10 minute intervals. Angled and horizontal mountings are possible, but vertical mounting is recommended to reduce condensation buildup in the fan. Horizontal mountings require a 1/4 inch hole drilled in the bottom (along with the proper drain insert and drainage tube) to allow condensation to drain. The diaphragm pressure switch should be positioned vertically for optimum sensitivity.

Dryers Deserve A Closer Look

It is more necessary today than in the past to have a clothes dryer exhaust systems inspected. Such an inspection is critical today because newer houses tend to have dryers located farther away from an outside wall; therefore, dryers tend to be vented for longer distances, and ducts are more often installed with sharp turns and bends to accommodate the structure of the home. As a result, dryer vents have more places to collect lint, and small animals and birds have more room to hide or nest. Also, there are more gas dryers being used today? Just another reason why dryer exhaust vent systems warrant a closer look.

People die, property is destroyed & energy is wasted
as a result of inadequate or clogged dryer vents.

Energy Usage Chart

Why Exhausting Is Critical

Moisture… a minimum of 1/2 gallon or more of water must be disposed of for every typical load of laundry. Because of the moisture, exhausting the dryer to the outside is a must. Indoor exhausting can create conditions that support mold growth and degrade indoor air quality.

Carbon Monoxide… Proper exhausting is of particular importance with gas dryers. In addition to moisture and lint, a gas dryer’s exhaust vent carries the byproducts of combustion, including carbon monoxide.

Clogging… A lot of lint is produced during the drying process, and lint can restrict or block dryer vents. A poorly exhausting dryer is not only less efficient, it can also be a fire hazard due to the extreme flammability of lint. Clogging can also cause moisture to accumulate and seep out the vent, leading to moisture damage.

Suggestions For Clients

bullet Have dryer and exhaust vents inspected and cleaned biennial or sooner if you notice a change in drying time.
bullet Always follow the dryer manufacturer’s recommendations.
bullet If the exhaust vent system is not up to current standard, have it replaced or corrected.
It is good practice to always run the dryer long enough so that the last few minutes push only hot, dry air into the vent. This will help to clear out any remaining moisture.
bullet Install a fire extinguisher in laundry area, but not over the dryer.
bullet Install smoke alarm in laundry area.
bullet Install (CO) alarm in laundry area (Gas dryer only).
bullet Clean lint filter before every cycle.
bullet Replace a damaged lint filter.
bullet Monitor exterior termination for flapper function and airflow.
bullet Use caution not to crush or kink transition duct behind dryer.
bullet Never operate a dryer while sleeping or away from home.
One of the best ways to save TIME and MONEY is to have your dryer exhaust vent cleaned! Keeping your dryer exhaust vent clean and free from lint may shorten your drying time by 50% or more. We have clients that say that after having us clean the dryer exhaust vent, the drying time of one load of clothes went down from 90 minutes to 25 minutes! Wow, now that is a significant difference! Not only for the clothes being dried but the consumption of energy to run the appliance and wear and tear on both the appliance and your clothing.

Why Not – Do It Yourself (DIY)?

Some people consider doing this themselves but this is not advisable. Here are a few reasons why you should not attempt this on your own:
It exposes you to dangerous microorganisms hiding in your dryer exhaust vent.
It could be dangerous to people who do not know the safety precautions involving large appliances.
You may not know how to adequately clean the dryer exhaust vent out properly, leaving much lint and debris behind.
Cleaning the dryer exhaust vent is not the same as cleaning the lint from your dryer lint trap. The process involves getting into the back of your dryer intake system and this is more dangerous than simply cleaning the lint out of the main filter area.
You need professionals who are used to this process and who are experienced to handle these kinds of cleaning jobs, to avoid the risk to yourself or your family by doing it yourself.

Reasons To Hire A Professional to Clean Your Dryer Exhaust Vent

Saves time and money.
Eliminates fire hazards with drying clothes.
Increases dryer efficiency.
Cleaning them yourself is dangerous.
Extends the life of your dryer.
Helps the environment.
Keeps your home cleaner and safer.
Cuts down on harmful bacteria and microorganisms.
Leaves a dangerous job to the professionals.

Do It For Safety!

Dryer lint builds up over time in your dryer exhaust vent and blocks your air intake from your dryer. This creates a potential fire hazard, makes your dryer work much harder than it is supposed to, and increases the likelihood of fires. Don’t take this risk with your family. Have the professionals at Apex Duct And Chimney Cleaning clean your dryer exhaust vent and get it running efficiently again. The experts at Apex Duct And Chimney Cleaning know how to clean your dryer exhaust vent and get it running at peak efficiency, which is good for the environment. And they can also lengthen the life span of your dryer and clothes. This will also save time on doing laundry, which is going to save you money as well.

If you want to save energy, time, and money, hire the professionals at Apex Duct And Chimney Cleaning to get your dryer exhaust vent cleaned. We WILL take the time to do it right, and help you stay safe. You will notice a big difference in your utility bill, and the cost it takes you to pay the professionals to clean it will pay for itself quickly each month when you notice the savings in your energy bill.

Home Fire Safety Information


Have a Plan
The most important thing to consider about home fire safety is to have a plan. Practice as a whole household proper procedures in case there is a fire. Pick a spot a safe distance from your home as a meet-up spot to gather in case of a fire. Fire extinguishers, ladders, and proper procedures for exiting a burning house or building will help keep you and your loved ones safe.
Take any and all alarms seriously
When a smoke or carbon monoxide detector goes off, it is for a real warning. Take all precautions seriously from the moment you become aware of an alarm or other problem such as seeing or smelling smoke. If an alarm goes off, GET OUT! It is important to notify the proper authorities, but do so after you have ensured your safety and to those around you.
Fire Extinguishers
Most fires start small and can be contained if acted upon quickly. Use fire extinguishers on small fires if available and accessible. Not only is a fire extinguisher a good protection, be familiar with its operation. Never operate a fire extinguisher if you do not know how to use it.
Take caution with closed doors
When evacuating a house that is on fire, always feel the wooden part of the door prior to opening it. If the door is warm or hot never open it. The door handle maybe hot enough to burn you very badly. Opening the door can bring more oxygen to the fire feeding it and possibly bringing you into more danger. Find another way out of the room. If you cannot escape, signal for help. Window ladders can be useful for second story rooms. Never use a non-approved ladder.
Stay low to the ground
Heat and smoke will rise, so being close to the floor will help keep you safer. Keeping low to the ground will help reduce the amount of smoke inhalation. Crawl and keep your hand on the wall to keep from being disoriented.
Once out Stay Out
Once you reach safety, dial 911 if someone has not already, and never re-enter a burning building. Meet up with other members of the home at a site that was previously chosen for this type of situation. Ensure everyone has been accounted for. Stay clear from danger and await for authorities to arrive.
Energy Usage Chart

Don’t let something like this happen to you.
Give us a call today to schedule an appointment!




[Click Here For A List Of Our Company Specials]

If you would like to schedule an appointment with our company the following TIPS will help assist in the completion of your scheduled appointment.

Our Dryer Vent Cleaning YouTube Videos External Link


CSIA , NCSG , CCP , GSCSG , NFI , PERC , NFPA , PFI , AGA , HPBA , USFA , DEDP , Cal/OSHA ) External Links

Pages: 1 2 3

Website Vistors As Of:  January 17, 2021
Website Vistors