Venting Dryers in the Attic

Clothes dryer venting into the attic.
Clothes dryer venting into the attic.

My dryer vents in my attic. What can I do to have it vented outside to prevent lint buildup and to make it less of a fire hazard? -Cindy

Hi Cindy,

You’re right to be concerned. In addition to being against most building codes and a potential fire hazard, venting a dryer in an attic can result in moisture problems which could lead to rot or mold in your attic. Check out our video on Dryer Vent Safety for more information.

If your laundry room has access to an outside wall, cut a hole and install a standard dryer vent. Be careful you don’t cut through any studs, electrical wires, or pipes in the process. If venting outside isn’t an option, you can vent the dryer out of the attic through the roof using a special roof vent to keep rain out.

When venting dryers for long distances, use rigid metal pipe with as few elbows as possible. Attach the sections together with metallic duct tape—rather than sheet metal screws—to prevent lint buildup around the protruding screw inside the pipe.

Check your dryer manual for the maximum length of pipe and number of bends allowed. It’s a good idea to make the vent pipe easily detachable in the attic to allow you to clean it from time to time.

If the vent is longer than recommended, a booster vent fan can be installed in the pipe to increase the distance. To learn more, see our Dryer Vent Extension video.



  1. What about the lint build-up issue? I just bought a townhouse and the dryer vents out the attic. The previous ownners dryer left lint buildup in the wall part of the pipe. The laundry is in the middle of the house in the master closet.

    • Hi Hope,
      Lint build up in dryer vent pipes can definitely be a problem, and the pipe should be cleaned periodically to remove it. Check out the Dryer Vent Safety link in the article above for more information. In your case, you might need to disconnect the vent pipe in the attic and fish a dryer cleaning brush with an extension handle down it from there to be able to reach the entire length of pipe.

  2. I also have a dryer vented through the attic and out to the roof. Every couple of months I’ve pulled the vent off where it curves just before it goes to the outside. I take a broom handle and tie a thick rag on the end of it and a rope on the other end. I push it down the vent shaft and pull it back up to clean. Lately, that wasn’t the problem. It’s the little bird that wants to constantly build a house in my dryer vent. I noticed the dryer wasn’t working normally when I discovered the bird nest. Every couple of days I would remove the bird nest only to find the bird had put more in it’s place. The solution – a $1.79 orange and black rubber snake. I put this snake on the roof just above the entry to the vent and the bird has not returned.

    • Hi Amy,
      Clever idea! If you have a dryer vent that goes through a wall, be sure to clean the flapper outside regularly so it closes and open properly. Otherwise, critters like birds, squirrels, and snakes might make their way inside through it!

  3. While cleaning my dryer tubing for lint which vents out of the roof, the 4″ lint brush which was screwed into a 3 ft extension came off and is now somewhere in the tubing between my utility room and my attic. How do i get it out?

  4. Our dryer vents out the gable end of our attic. Living in the North East our winters get well below freezing. Do I need to insulate exhaust pipe?

    • Hi Anthony,
      If your dryer vent pipe has condensation forming on the outside of the pipe, I would insulate it. If not, it should be okay.

  5. I found that our dryer vent was venting into the attic. I have temporarilly fixed it by extending with flexible metal ventpipe and attaching this to the base of one of the roof turbine-syle exhaust fans (not one with a motor, the passive wind driven kind). Is this an adequate solution?


  6. I just bought a home Feb 28 and the dryer was vented to the attic. It has caused cracks where the ceiling joins the wall. I had to hire a home builder to have the dryer vented to the outside so the house would pass county inspection. I never even thought of the fire hazard till reading this article. Now I’m going to clean the lint out of the attic and lay another layer of insulation while I’m at it.

  7. I called and left you a message regarding installing a wall dryer vent onto the roof. (And my husband kept wondering why there was a screw set in the middle of the flapper because it would weigh down the flapper door too much when the air is forced up and out the roof). Well, he’s going to attached everything first to try it to see if the flapper door will open when the dryer is on. We also added a thin wire across the opening with 3 very small metal tape flags to see the air come through. We haven’t tested any of this yet but I’m really concerned about our “Mickey Mousing” a vent that isn’t meant for the roof. It does point on angle same as the roof. It’s practically a straight shot to the roof (through the attic) from the dryer. Should we dump this plan for safety reasons and just get the roof vent?
    Thanks for any advice you might have…Lin

  8. My dryer vent goes through the attic to the top of the roof. I am concerned about not being able to clean out the piping of build-up. Is this causing a fire hazard?

    Thank you for your help.

  9. We just noticed that our dryer vent came disconnect from the dryer. We don’t know how long it was disconnected for but there was a layer of lint on the wall and on the floor that we had to clean. My concern is that there is also a good amount of lint that looks like it went into our wall through the space in the sheet rock cut out for the dryer vent. I tried to get as much of it out with my hand but I know there is more. I think the only thorough way to get all the lint out cleanly would be to cut out the sheet rock and clean it, but I don’t know if this is needed/recommended?

  10. I have the same problem as this comment from 2011, but I didn’t see an answer on here??

    don cannon Says:
    January 30th, 2011 at 12:34 pm
    While cleaning my dryer tubing for lint which vents out of the roof, the 4″ lint brush which was screwed into a 3 ft extension came off and is now somewhere in the tubing between my utility room and my attic. How do i get it out?

  11. When our dryer was replaced, we decided to bring the dryer venting system (early 1960) up to code by replacing the tubing that vented into the attic. That is, the old material type tubing simply ended by a overhang side of the house, where it exhaused into the attic and not outside. Now, the new metal tubing exhausts out of a gable side of the house through the wall at attic floor level via a metal exhaust flap we bought online. (Only plastic exhaust flaps were available at places like HomeDepot, Walmart & Lowes.) To clean out the tubing, every other year in the Spring (odd years), we merely disconnect the vent tube from where it connects to the ceiling in our wash room, insert out leaf blower into the tube where it enters the attic, and then turn on the blower to blow out dust that has accumulated over the past year. (I’ve watched dust exit. Also saw a couple ping pong type balls (cat’s toys) exit that hubby blew out as a joke once.)

  12. 23 unit two story condo building. All lint vents into attic. Florida 1985 reg insists all buildings after that must vent outside. Unfortuantely older buildings are stuck. Our attics are full of lint…thirty years of lint. After pressure they are finally cleaning lint hoses. What can we do about the 30 years of lint in attic.
    Thank you.

  13. Had a company over to clean out the dryer vent. We live in NC and have a home built on a slab. The dryer line is under the slab and has been rusted through and now water and dirt are starting to clog the vent. The laundry room sits next to the living room so there is no straight route left, right, up and the slab is down. Do you have any suggestions?

  14. Wayne,
    If your dryer room has a standard 2×4 wall (3 1\2″ studs) and your home is single story, then there is hope. You or your contractor can install an in wall insert that will exhaust up through and between the sheetrock and through the top plate and then through the roof or the nearest soffit. Take which ever is shortest and has the least amount of bends. There’s a bit of work involved, but it will be a permanent solution. Do not pay mind to naysayers who say the roof is not an option, as well over 50% of new spec homes are built this way. Laundry rooms just are not being built on outside walls these days. Google “Dryer Jack” and order their roof vent and any angle sections you need, as their 45 & 90 deg smooth angle pieces work very well. You can get 5′ and 2′ sections at HD or most hardware stores. Also, stick with galvanized as it’s more rigid and will not crush as easy as aluminum. You will want to check for condensation on the attic pieces during winter. If there is condensation, insulate the attic pipe.

  15. I bought an old house with a gas dryer. The dryer is in the kitchen on the inside wall. So its vented through the wall and comes out above and to the side of the back door. Is there any way to clean that? Or is there some other way to vent it outside? It’s about 12 ft. long I think.

  16. Our dryer is vented through the floor. Just a hole cut in the floor and put the vent hose through it. It was this way when we bought the house. Is this safe?

  17. I have a booster fan in the attic for my dryer. Should it be running the entire time the dryer is on? Last time I was in the attic and the dryer was on but the fan was not running. Does this mean it’s broken?

  18. Bought a single story in north Texas I knew when I purchased the house the dryer was venting into the attic. I found no damage other than lint build up, it was dropped over a soffit inlet which just makes no sense to me as air was meant to come into these not go out. The issue I have is I was going to run from the attic floor to the roof and out with a roof vent in 4″ smooth aluminum duct. The pluming in the wall is similar to a periscope going 8 feet up into the attic inside the wall it is rectangular and has a 4″ connection at the laundry room, the kicker is it has a 3″ round connection in the attic. Can I just adapt a 3″ to 4″ coupling? The run will be 12feet the current soffit run is 15ft but attic pipe is 3″ will I have issues with this new setup?

  19. We live on the top 3rd floor of a condo so my vent is going up through the ceiling and outside the condo.
    I’m having problems with the lint acumalating in the dryer and getting into my cloths . Dryer vent is always clean but still lint . Does the vent through the roof a problem or kinking of the hose behind the dryer.

  20. Electric dryer has airflow and heat but back flow due to blockage below goose neck roof cap below roof sheathing in attic. Vertical exhaust flue clean out found SOAKED lint in flue. Took two rolls paper towel to dry up floor once flex hose removed from dryer when rain water or humid lint came out. Suggestions on how to remove blockage as 4″ brush didn’t do it and no airflow out goose neck roof cap vent ?
    Dead squirrel carcass in vent below roof line ?
    Disconnect flue piece in attic below vent?


  22. I have a townhouse in renovating a bathroom, I noticed dryer vent exhaust into a crawl space between first and second floor. is this a fire hazard and There is no way to exhaust outside is there another option to venting my dryer. someone mentioned a contained lint box that can be attached to the wall with a filter system that needs to be cleaned ofter. do you recommend this or just venting in garage although that seems like it would make lots od dust and lint in garage? suggestions please. Thank you
    Karen, Florida

  23. Do you know how many homes catch fire due to incorrect dryer duct installation, terminations, duct runs and poor maintenance every year? It’s a lot for something that’s 100% preventable. Facts about home clothes dryer fires:
    •2,900 home clothes dryer fires are reported each year and cause an estimated 5 deaths, 100 injuries, and $35 million in property loss.
    •Failure to clean the dryer (34 percent) is the leading cause of home clothes dryer fires.
    •More home clothes dryer fires occur in the fall and winter months, peaking in January.

    So I bought a 70 year old home with known laundry access issues, but I knew it could be fixed. The previous homeowner used a water/lint trap inside the house to vent their dryer. That’s unsafe and unhealthy. Don’t do this for more than a week or two. In fact, don’t, just don’t. Think about it, you are venting dirty humidity into your house. The tiny lint particles are flammable and noxious to your own health.

    The 3-4 years the last homeowner was here, the venting left some lint residue on the walls near the laundry area. Ick, and she had an infant in the house. With access to so much information available on the internet. Once someone knows there’s a problem, one can no longer justify their ignorance. My laundry area is on an internal wall so the only method for venting a dryer is to push it out through the roof because it’s too long of a distance to run duct through the attic to an exterior wall. Evidence says that horizontal run vs vertical run is negligible. What impacts dryer venting the most is obstruction from screws (not allowed), a screen on the vent (not allowed), the ripples in flexible venting (not allowed in concealed spaces) and 90 degree turns . The reference for correct dryer venting is in the International Residential Code M1502.

    So, the cost to add a dryer vent outside the home? In the ballpark of $600 from a licensed contractor. You could do it yourself for about $100 but do you know what you’re doing? The contractor removed cabinets, cut through sheetrock, cut a hole through my ceiling and roof and added a dryer vent roof jack. The rigid dryer duct is now concealed nicely in the wall behind the upper cabinet. They did some sheetrock work and the sanding, texture and painting was left to me.

    I would keep an eye on the contractor even if they are licensed. I had the roof replaced a week later and when they removed the dryer vent, it wasn’t attached to the duct because the contractor crew used flexible duct in the attic space. Glad I didn’t have the appliances in yet. Flexible dryer ducts are not designed for concealed spaces, for obvious reasons. The dryer duct must be rigid through walls and the attic space to limit the chance of duct separation. You don’t want this venting into your attic either; think mold. Anyways, I had the contractor come back out and fix that. In the process, they put on a different dryer roof jack with no screen and it had a backflow flapper to limit moisture and wind pushing down into the duct. They must have thought I’d have heartburn if that wasn’t to code either. They were right, I compare their work to building codes, which I always do.

    When the contractor is done, set the camera on your phone to use flash and take some photos inside the duct. Make sure there are no screws, attic debris, shingles or flexible duct in there. It might be a little more effort but have a friend look in the attic space and confirm the type of duct running through the attic. Practice some due diligence because the health and safety of your family and home are at stake here. The crew tried to tell me the code just changed. I didn’t want to argue but I know that this particular mechanical code has been around for over a decade. Besides, I’m fairly certain that manufacturer’s installation instructions say the same thing when it comes to dryer venting types in concealed spaces.


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