The dryer in your Fountain Square basement blows warm, damp air into a plastic lint box, and you want to know: can you vent a dryer inside the house in Indiana? No. Indiana's home code says a dryer vent has to end outside the building. In Marion County, the housing code says the same for a home of any age. A gas dryer vented indoors can also put carbon monoxide, a gas you can't see or smell, in the house.
If your dryer burns gas, start here:
- It's gas and you know it vents indoors: don't run it until it vents outside.
- Anyone feels sick, dizzy or gets a headache while it runs: get everybody out into fresh air, then call 911. The CPSC says to get to fresh air right away.
There's one exception to the state's outdoor rule, and it's a ductless condensing dryer. An indoor lint-trap kit isn't one.
Find your situation:
- You're putting in a new dryer or a new vent: the duct has to end outside. That's the state code for new work.
- Your dryer burns gas: vent it outside, always. The code says the vent has to carry what the flame gives off out of the building. If it vents indoors now, stop using it until that's fixed.
- You have a ductless condensing dryer: the state code's outdoor rule doesn't apply to it, as long as it's listed and labeled as one. Marion County's housing code doesn't mention ductless dryers. Ask the county health department if you're unsure.
- You bought an indoor lint-trap kit: the kit doesn't change the rule. The air still has to go outside.
- The vent ends in the garage, attic or crawl space: that isn't outside, so it doesn't meet the state code for new work, or Marion County's housing code.
- An indoor vent was already there when you moved in: in Marion County it still has to vent outside. The housing code puts that on the owner. In other counties, ask your town's building office.
Can I vent my dryer inside my house?
No, unless it's a condensing dryer built to run with no duct. For every other dryer, the 2020 Indiana Residential Code, section M1502.2 says the vent has to carry the moisture outdoors.
That damp air is the point of the rule. A dryer pulls water out of wet clothes, and the code wants that water sent outside and not into your laundry room, your garage or your basement.
Samsung's manual for its DVE45T6000 dryers says venting outside keeps "large amounts of lint and moisture" from being blown into the room. The U.S. Fire Administration says dryer air sent into an attic, crawl space or wall "can cause indoor air deterioration and mold buildup." That goes for electric dryers too.
Read the exact wording
"M1502.2 Independent Exhaust Systems Dryer exhaust systems shall be independent of all other systems and shall convey the moisture to the outdoors. Exception: This section shall not apply to listed and labeled condensing (ductless) clothes dryers."
What dryer makers say
The two manuals we read agree with the code. GE's install guide for its GTD42EASJWW dryer says the dryer must be vented outdoors. It also lists places the air can't go, like a wall, a ceiling, an attic or a crawl space.
Samsung's manual for its DVE45T6000 dryers is even shorter. It says all dryers in the U.S. and Canada must be exhausted to the outside.
Read the exact wording
"This dryer must be exhausted to the outdoors." and "DO NOT exhaust into a chimney, kitchen exhaust, gas vent, wall, ceiling, attic, crawl space, or concealed space of a building."
If your dryer burns gas
This is the part that scares us. A gas dryer has a flame inside, and its vent carries off more than damp air. Vent it into the house and carbon monoxide from that flame can stay in the house with you.
GE's install guide for a gas dryer names carbon monoxide. It's one of four things a gas appliance can give off when the gas doesn't burn all the way. GE says venting the dryer outdoors cuts the exposure down, and the same guide says the dryer must be exhausted to the outdoors.
Read the exact wording
"Gas appliances can cause minor exposure to four of these substances, namely benzene, carbon monoxide, formaldehyde and soot, caused primarily by the incomplete combustion of natural gas or LP fuels. Properly adjusted dryers will minimize incomplete combustion. Exposure to these substances can be minimized further by properly venting the dryer to the outdoors."
From GE Installation Instructions, Gas Dryer, Pub. 31-16736 (GE's own copy)
The fuel gas part of the Indiana code, section G2439.1, asks for the same thing in broader words. A gas dryer's vent has to carry the moisture and anything the flame gives off to the outside of the building.
If a gas dryer vents into your house or garage right now, stop using it until the vent runs outside. If anyone feels sick, dizzy or gets a headache, get everybody out into fresh air and call 911. Don't wait on it.
Marion County's housing code has an alarm rule too. Under section 10-312(b), an owner has to put a carbon monoxide alarm in a dwelling "in homes with non-electric appliances and fireplaces". Those are the county's words. The rule doesn't say if a home needs both a gas appliance and a fireplace, or just one. Our guide on heating a house with a gas oven covers the signs of carbon monoxide and Indiana's alarm rules.
Read the exact wording
"G2439.1 (614.1) Installation Clothes dryers shall be exhausted in accordance with the manufacturer's instructions. Dryer exhaust systems shall be independent of all other systems and shall convey the moisture and any products of combustion to the outside of the building."
The one exception
A condensing dryer is a ductless dryer. The code's outdoor rule skips it, but only when the dryer is listed and labeled as that kind. A regular dryer with the duct pulled off isn't one.
Is it against code to vent a dryer inside?
Yes. The state code bans it in new work. It bans it in changes to a house, too. Marion County's housing code bans it in any home people live in. The state code says the duct has to end on the outside of the building, and the garage, the attic and the crawl space don't count as outside. Outside means outside.
It helps to know who does what. The state writes the code, and it governs new work and alterations. Indianapolis runs the permits and the inspections.
The Indiana Department of Homeland Security says the building rules enforced across Indiana are the state commission's rules, with no local changes. That's the state's view, and the state says its view isn't binding, while Marion County's housing code is a separate rule from the building code.
Read the exact wording
"In effect, this legislation has created a framework where the substantive building and fire safety laws that are enforced throughout Indiana are the unamended rules of the Commission."
From Indiana Department of Homeland Security, Boards and Commissions
What about a vent that's already there?
In Marion County, an old indoor vent breaks the housing code too. Section 10-407 of the county housing code says a clothes dryer must be vented to the outside. The owner has to see to it. It covers every home, no matter when it was built. The state code speaks to new work and alterations. Outside Marion County, ask your town's building office.
Read the exact wording
"…irrespective of when or under what code or codes the building or structure was originally constructed or rehabilitated." (Sec. 10-103) "No dwelling may be inhabited unless the provisions of this Article are met… the property owner is responsible…" (Sec. 10-400) "Clothes dryers must be properly installed, maintained in good working condition, and vented to the outside." (Sec. 10-407)
The county health department's Housing and Neighborhood Health team enforces this housing code, and it works from complaints. You can file one online or call 317-221-2150.
What are the rules for dryer venting?
The duct has to end outside, with a backdraft damper and no screen or mesh over the end. For the exact spot, section M1502.3 sends you to your dryer maker's install guide, and if the guide is silent, the end of the duct sits at least 3 feet from any opening into the building.
Two more sections fence it in. The dryer needs a duct of its own under M1502.2. And M1501.1 bars the attic, a soffit, a ridge vent and a crawl space as places to send the air.
Read the exact wording
"M1502.3 Duct Termination Exhaust ducts shall terminate on the outside of the building. Exhaust duct terminations shall be in accordance with the dryer manufacturer's installation instructions. If the manufacturer's instructions do not specify a termination location, the exhaust duct shall terminate not less than 3 feet (914 mm) in any direction from openings into buildings. Exhaust duct terminations shall be equipped with a backdraft damper. Screens shall not be installed at the duct termination."
Getting the duct outside is step one. The rest of the rules are in our guide on how long a dryer vent can be in Indiana. It covers the length of the run, what each bend costs and what the duct is made of. The duct needs cleaning too, so see how often to clean a dryer vent.
What is the Indiana residential code for dryer vents?
It's the 2020 Indiana Residential Code, known in the state's rule books as 675 IAC 14-4.4. The state's list of building rules shows it's built on the 2018 International Residential Code. In its 2019 final rule, Indiana changed just one dryer vent section, M1502.4.2, on how the duct is held up and joined.
Nothing in that change opens a door to venting indoors. Our guide on how long a dryer vent can be in Indiana walks through what Indiana changed, line by line.
A check you can do today
You don't need tools for this one. It takes ten minutes. Start with the fuel, then walk the path the air takes.
- Check the fuel first. If a gas line runs to the dryer and you already know it vents indoors, don't run it. Stop here and get the vent fixed.
- Find where the duct leaves the dryer. Follow it as far as you can see. If it ends indoors and the dryer is gas, stop. Don't run it.
- Look in the garage. Peek into the attic and the crawl space from the hatch, if you can do it safely. A duct that stops in any of them isn't vented outside.
- Run the dryer and go outside. Look for a hood on the wall with a flap that opens.
- Feel for warm air at that hood. If there's none, the duct may end somewhere else.
What to write down before you call
If you'd like a pro to look at the vent, have these ready:
- Your dryer: the make and model, and whether it's gas or electric.
- Where the vent ends now: the garage, a box in the laundry room, the attic or outside.
- The nearest outside wall: about how far it is from the dryer.
- What you've seen: damp air or lint in the room where the vent ends.