Depending on the design of your house, it may not be all that easy to vent your dryer outside. Plus, you want to conserve as much heat as possible to save on your energy bill. So is venting inside dangerous?
It’s not safe to vent gas or electric dryers inside. Gas dryers emit carbon monoxide, which is highly dangerous. Electric dryers don’t release carbon monoxide; however, dryer sheets and fabric softeners contain toxic chemicals that may cause respiratory problems. Venting inside also causes mold and condensation problems.
In this article, you’ll learn:
- The dangers of venting inside
- Whether indoor dryer vent kits are safe
- The safest options for venting your dryer outside
Health Risks of Venting Inside
Venting a dryer indoors means that you are releasing microscopic particles of lint. This is a combination of natural and artificial fabrics that are easy to breathe in. Many of these materials are known allergens and may even be toxic in some cases.
Airborne lint will continue to float throughout your home and on into other rooms. The lint can also build up in clumps near power outlets and heaters.
Other safety issues include:
- Mold – Once mold takes hold of your home, it becomes an expensive challenge to try and remove it. Chemical mold treatments for walls and ceilings are premium products and take time to apply. In extreme situations, you may need to employ the skills of a professional to kill off patches of mold.
- Humidity – Humidity on its own is less of an issue, but it will condensate around the colder areas like windows and metal piping, causing rust and rot. Humid air will also reduce the efficiency of the dryer , taking longer to dry your clothes while consuming more power.
- Fire – Lint and other fine particles will separate from the clothes and blow through the exhaust port. This lint can settle around power outlets and heating elements, which can create fire hazards.
- Toxicity – Venting the exhaust gases into your home can cause serious issues, even with electric dryers. A dryer will release chemicals from cleaning products remaining in washed clothing into the air. These aerosolized detergents can cause short-and long-term breathing issues.
Electric Dryer vs Gas Dryer
The two main choices of clothes dryer are electric and gas, though gas is more cost-effective and quicker at drying large volumes of clothing.
While a gas dryer is more powerful, there are many health and safety issues to consider when installing and running either machine. An electric dryer can still be a danger, even though it does not combust a fuel.
- Electric dryers are less complex to install and better for occasional use and smaller loads.
- You should still vent an electric dryer to the outside or through a filter to reduce the dangers to the occupants of your home.
- The emissions from an electric dryer can create an aerosol of water vapor, lint, and fumes from detergents.
- Gas dryers create large amounts of carbon dioxide and monoxide during the process of burning gas to generate heat.
- Carbon monoxide is deadly, colorless, and odorless. Low exposure can cause headaches and vomiting, while high concentrations can lead to brain damage and death within five minutes.
- With a gas dryer, it is even more important that the venting directs all fumes and vapors to the outside.
Are Indoor Dryer Vent Kits Safe?
There are two main types of dryer vents: indoor and outdoor. The best and most common way of venting to the open air is through a duct pipe. Though it is possible to vent indoors with certain dryers with the right filters, some dryers are safe to use without any vents.
Building code M1502 of the IRC states that the dryer’s manufacturer’s recommendations should be followed. In some states, it is illegal to use exhaust pipes beyond a certain length. The code specifies that the duct should not exceed 35 feet (10m), so you may not even have the option of running the pipe to the outside.
The code also states that the dryer should not exhaust out to any part of your home, even the attic. Regardless of the code, the many health and safety issues with venting your dryer into your home should be enough to discourage you from trying it.
How to Vent a Dryer Without a Vent to the Outside
If the building codes allow for it, you may want to use the heat from the dryer to warm the rest of your home. Though venting indoors is not something you would do with a gas dryer.
For safe venting, there are several options for your dryer’s exhaust when you do not have a vent to the outside.
Ducting the exhaust out through a window is one of the simplest and cleanest methods. Though you do need to ensure that there are at least three feet (1m) of pipe extending outside to prevent blowback.
And when you stop using the dryer, you can bring the pipe back indoors and close the window. This is a solution without mess or the need to cut a hole in your wall. If it is cold, you may want to use a window kit to fill in the open section of the window while the dryer is venting.
Attic ducting is outside of the building regulations in most states. But, if you do send the exhaust to your attic, use a lint trap. A reusable filter in the trap catches the lint. The filter is washable, and you should try to empty it monthly.
The trap prevents lint from blowing around in your attic, making everything you store up there dusty. Lint can also build up into flammable clumps around hot lightbulbs.
Exterior Wall Ducting
Exterior wall ducts are the best way of venting a dryer, as you can make the duct pipe short and keep the back pressure low. You can install a dryer wall duct that closes when there is no airflow. Wall ducts prevent cold winds blowing back in and rodents using the duct as a home.
Roof ducts are useful for gas dryers where you want to get all the exhaust fumes out of your home through the roof. A roof duct will help disperse lint out and prevent backdrafts. Though, in some states with high levels of snowfall, roof ducts may become covered and blocked.
A less-known option is to install a ventless dryer, which is a good alternative for homes with smaller wash loads. The dryer circulates the humid air through an internal filter to trap the lint, which is easy to remove from the filter after each load.
A ventless dryer will also condense the water vapor as it circulates, collecting it into a drip tank or running it straight out to your main drain. Ventless dryers are a perfect solution for a small apartment or RV, but these dryers can take longer to dry your clothes.