Are Indoor Dryer Vents Safe? What You Need To Know

Giovanni Valle is a licensed architect and LEED-accredited professional and is certified by the National Council of Architectural Registration Boards (NCARB). He is the author and managing editor of various digital publications, including BuilderSpace, Your Own Architect, and Interiors Place.

Clothes dryers are found in almost all homes, and they provide a quick and efficient way to dry clothes. However, all of that warm air they produce has to go somewhere, and its effects are probably something you have never really thought about. If you are venting your dryer into your home, you need to stop doing so.

Indoor dryer vents are not safe. They can cause health problems due to a build-up of mold and structural damage due to the increased humidity. They can also be a fire hazard as the lint they spew into the air is highly flammable. Outdoor dryer vents are the safe choice.

Keep on reading this article for more information about indoor dryer vents and why people use them, whether they are legal or not, and why they pose such a risk to your health and home. Let’s dive right in.

What Is an Indoor Dryer Vent?

When running, a dryer generates excess heat that needs to be removed through a vent. There are two types of dryer vents: indoor and outdoor.

An indoor dryer vent does not go through a wall or a window like an outdoor one does. It instead vents into a space in your house, such as the laundry, or into an attic space. This kind of dryer vent is typical in spaces where the venting system must be contained within the home, such as in an apartment or a condominium.

Why Do People Vent Dryers Into Their Homes?

There are a variety of reasons why people have indoor dryer vents. Some have no choice but to have a contained system because of the way their home is built. Others choose to install them, which is a mistake.

Some people vent their electric dryer indoors in cooler months to save on heating costs. Doing this also doubles as a humidifier, which can be pleasant in winter when the air is dry, and many people find their skin and hair drying out.

Are Indoor Dryer Vents Legal?

Many homeowners wonder if indoor dryer vents are legal. The answer is no for many places. According to section M1502 of the International Residential Code, dryer vents must be “terminated outside of the building.” In many places, indoor dryer vents are essentially a no-no, and homeowners risk receiving a fine if they are venting their dryer indoors illegally.

Dryer venting is subject to home inspection in the US. The IRC governs most home inspectors, but there may be codes with other guidelines in some states. The guidelines are for one- and two-family homes of three stories or less.

The regulations for dryer vents aim to prevent any damage or negative side-effects that may arise from incorrect dryer venting, such as fires or damage to the home structure caused by humidity.

Check the regulations for where you live if you have an indoor dryer vent and want to keep it – but after reading the rest of this article, you will likely change your mind.

Is It Safe To Vent Your Dryer Indoors?

If you have a gas dryer, you absolutely should not vent it indoors. This is because gas dryers emit carbon monoxide, which is incredibly dangerous.

If you have an electric dryer, you may be wondering if it is safe to vent it indoors, especially if you live in an apartment or a condominium where there is no other choice. Unfortunately, venting a dryer indoors, even an electric one, is not a good choice.

Serious Mold Problems

A 2008 article by North Dakota State University warns against venting your clothes dryer into your home because of the high risk of mold.

This is because washed wet clothes can contain up to two gallons of water. When the dryer removes this water, it can add too much moisture to the home’s atmosphere. As such, when the humidity rises in a home, it becomes a lot damper, creating the perfect living conditions for mold.

Mold is certainly not a thing to ignore. It can cause extremely dangerous health problems, including allergic reactions. Mold also tends to grow in inconspicuous places, so many mold allergy sufferers may not even realize what is setting off their symptoms and causing them to feel so bad.

Increased Humidity

Another major problem that can arise from venting a dryer indoors is the increased humidity in the house. While some people purposely vent their dryers indoors during winter precisely because they want this extra humidity, it is actually doing more harm than good.

Excess humidity can wreak havoc on your house’s structure. Most common building materials, such as wood and drywall, will absorb the extra moisture and begin to rot. This can cost thousands of dollars in repairs. Humidity can also damage your roof, insulation, structural support, and even your attic if you are venting into it.

Condensation is another big issue. When it builds up on areas like your windows, it can damage the structure of them.

One final reason is that your clothes will probably take longer to dry, defeating the whole reason you have the dryer in the first place!

Fire Hazard

While dryers can catch most of the lint with their lint traps, they will not catch every bit of it. Some lint escaping through the dryer’s exhaust is unavoidable.

Lint is highly flammable, and when venting inside, it will accumulate quickly. Anywhere that you vent your dryer inside instantly becomes a much higher fire risk, but mainly if you are venting your dryer into places such as the attic.

Lint is also an allergen and can cause problems similar to those mentioned when discussing mold issues.

Air Pollutants

Another significant risk caused by venting a dryer indoors is the increase of pollutants into the air. If you vent your dryer inside, you pollute the air in your house with the chemicals in the detergents. These can be damaging for your health in many ways and can cause allergic reactions in many people.

What Can You Do Instead of Venting Your Dryer Indoors?

If you have been venting your dryer into your home, even if it is into a bucket of water, you need to stop immediately and change to an outdoor vent. Don’t use a corrugated plastic pipe, however, as they easily trap lint inside. They can also start to sag with the accumulation of lint, making it difficult for any air to pass through. Always go with a smooth metal pipe for a dryer vent.

It is possible to have a dryer vent pipe that goes around corners but make sure the turn is gradual; otherwise, you again run the risk of having lint trapped inside the pipe, causing a fire hazard. It is best to go with the recommendations of your dryer’s manufacturer.

If your dryer vent pipe covers a long distance, it can be a good idea to install an exhaust fan in it to push the air through more effectively. This will stop large amounts of lint from getting caught in the vent pipe and potentially starting a fire. Again, this should only be done with professional advice, and you can not use an exhaust fan to “boost the performance” of your dryer.

Don’t try to install a dryer vent pipe without the proper guidance. If something goes wrong, you potentially have a big fire hazard.

If you have a dryer but no way to vent it to the outside, consider alternative options for drying your clothes, such as a clothesline or going to a laundromat.

If that is not an option, try to run a temporary exhaust pipe out of a window or open up windows and doors to increase the airflow in your home when using your dryer. Always make sure to also clean your dryer’s lint trap regularly to prevent a potentially flammable build-up.

You should not vent your dryer into a bucket of water. Some people think it is a good way to contain the lint that would otherwise be blowing all over the house, but it will cause the same problems that would occur if you were venting it inside in another way, deeming it ineffective. It can cause an increased amount of moisture in your house – in fact, it can cause even more moisture in the air than if you weren’t venting it into the bucket!

Final Words

It is essential to understand the potential risks associated with venting a dryer indoors, like fire hazards and air pollutants. In many places, it is illegal, and you risk being fined. Venting a dryer indoors can also have serious adverse effects on your health and the structural integrity of your home.

Whenever possible, always vent your dryer outdoors or switch to another method for drying your clothes. It is easy to find a new solution to your dryer venting problem. Making a change will not only protect you from a fine but will also save your health and your house.