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Community and Q&A

Venting a Dryer in the center of the house

h85sBVyrof | Posted in General Questions on

My house is on a slab. A room addition was added to the back of the house. This left my washer and dryer in the middle of the house. Right now we have the flexible hose running into the attic. I know this is not the way its supposed to be. I have no idea how to fix this problem. Any idea would be greatly appreciated. I asked about moving washer and dryer into the back of the house. I was told that the water line is the problem with that. You cannot tap into it. The pipe is not big enough. Help!

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  1. h85sBVyrof | | #1

    Its vented in the attic - not through the roof. Does it need to go through the roof? Is there a special kind of pipe I need to use to do this? Would this pass code if I chose to sell the house?

  2. wjrobinson | | #2

    Kay, keep going up through the roof.

    Search Google shopping, dryer roof vent.

  3. wjrobinson | | #3

    My HVAC contractor runs vents for me sometimes, all in metal ducting and it should be code, call your code office.

  4. h85sBVyrof | | #4

    So run metal ducting through the roof? I will call the code office. Do I need a roofer to make sure its done right on top of the roof? Flexible hose from dryer will connect to this metal ducting? I have had numerous people look at this and nobody has been able to tell me this. They just shake their heads and leave me with my problem. Sounds like I need to get a HVAC person to give me a estimate?

  5. h85sBVyrof | | #5

    I thought about trying to find Bob Vila for help!

  6. GBA Editor
    Martin Holladay | | #6

    There are several ways to duct your dryer:
    1. Through the roof, as AJ suggests. I don't like this approach, because the dryer vent will discharge ugly lint on top of your roof shingles.

    2. Through your gable wall, assuming you have a gable wall.

    3. Through your first-floor wall. This option will require you to build a soffit (a box near the ceiling) to hide the duct, which should be routed near the ceiling until it reaches an exterior wall.

    You need to install metal ductwork, without any sheet-metal screws penetrating any of this joints.

    Since it sounds as if you are unfamiliar with this type of work, you should hire a contractor to install your dryer vent.

  7. h85sBVyrof | | #7

    Thank you. This sounds like it would be cheaper to do rather than digging new water lines and moving the washer and dryer.

  8. davidmeiland | | #8

    Agree with Martin and AJ that you should run it out the roof or sidewall using sheet metal pipe. You need to pay attention to the manufacturer's instruction regarding total length of the pipe run. You want the duct as straight as possible with as few turns as possible. Insulating the pipe and orienting all seams to the top will minimize condensation problem in the attic.

  9. h85sBVyrof | | #9

    If I take it up through the roof then it would be a straight I believe. Does a heat and air person do this kind of work or who? I am not sure who to even call to be honest. I live in Lex, KY

  10. GBA Editor
    Martin Holladay | | #10

    You can hire an HVAC contractor or inquire at your local appliance store.

  11. h85sBVyrof | | #11

    Ok. Thanks for your help. At last I have atleast a idea that this situation is not hopeless.

  12. davidmeiland | | #12

    Kay, a lot of general contractor or handyman types can do a good job of installing a duct like that. If it goes through the roof, I would be leaning towards a GC over an HVAC person, because they will need to do some roofing. If I were you, I would call a couple of the larger and more reputable remodeling companies in town and see if they can recommend someone for a small but important job like this. You might have to get past the person who answers the phone and talk to a project manager in order to get good leads. Another place to ask is a nearby lumber yard or building center--find a salesperson at the contractor's counter and see who they know.

    One thing to think about is future cleaning of the outlet end of the duct. In most cases it will slowly build up lint, and you'll have to get access to it to clean it. A steep roof is not the ideal place for this, obviously. A gable end where you can use a short ladder is probably easier.

  13. h85sBVyrof | | #13

    Very good information. Thank you so much. I cannot tell all of you how much I appreciate your input. I will not go into detail but I was left with numerous problems like this. For this truly seemed impossible to solve. You guys are giving me great advice. Signing up for this, I never dreamed I would truly find solutions. Nice to know there are people out there who care.

  14. gL3WFYnfXo | | #14

    Someone needs to speak to the fact that this pipe needs to be insulated. In the winter, you will have very warm air traveling through the vent and very cold air in the attic! Hence, condensation. It will run down the outside of the metal duct and soak the first thing it hits.

  15. gL3WFYnfXo | | #15

    Also, if you run the duct in a boxed down soffit, be sure to insulate. I have seen condensation form in the summer when an air conditioned house causes water to form on the warm dryer duct. It was a mess! Be careful.

  16. davidmeiland | | #16

    Seems to me all the potential condensation is going to be on the inside of the duct. If it's installed nicely there should be no seams or joints where air or moisture can leak out. The hot air coming from the dryer will heat the pipe significantly, and it won't be a condensing surface for long. Most dryers continue to move air for a period at the end of the cycle, and the residual moisture gets evaporated. I suppose if the pipe is vertical there is a chance that some moisture could run back down to the bottom, where the dryer is connected to it. Obviously an install in the middle of the house is not ideal. I have usually been able to put the dryer against an exterior wall and use a dryerbox with one elbow and a few inches of pipe to vent it. That's the best case.

  17. GBA Editor
    Martin Holladay | | #17

    Condensation forms on cold surfaces, which is why you often see condensation on uninsulated forced-air ducts during the summer, when the air conditioner is running.

    Unless something is terribly wrong, you don't see condensation on dryer vents. These ducts are warm, not cold.

    If you install an uninsulated galvanized dryer vent in an attic, the duct will indeed be cold during the winter when the dryer is not operating. Once the dryer starts up, condensation could form on the inside of the duct. But that condensation is quickly evaporated by the fast-moving hot air produced by the dryer. Assuming normal care in duct assembly -- details that slope the duct toward the exterior, and taped joints -- you won't have any problems.

    Of course, insulating the duct is fine. But these ducts don't usually have condensation issues.

  18. h85sBVyrof | | #18

    Advice truly appreciated!

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