Insulate the bathroom vent hose to outside?

Discussion in 'General Home Improvement Discussion' started by drewdin, Mar 11, 2013.

  1. Mar 11, 2013 #1

    drewdin

    drewdin

    drewdin

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    Hi Guys,

    I was in the attic the other day and i noticed the flexible duct that goes from my bathroom vent to the roof was pretty flimsy, is it worth insulating the ductwork and sealing the cap on the roof?

    I tried a few google searches and it looks like there could be some condensation issues if its hot in the bathroom and cold in the attic and vice versa.

    My question is, is it worth it? Thanks
     
  2. Mar 11, 2013 #2

    nealtw

    nealtw

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    Yes you want to get the vapour out before it has a chance to condense. Condensing while in the attic may cause water to drip back into the fan or to lay in horizontal pipe in the attic. When it freezes it can open seams in the duct and appear like a roof leak.
     
  3. Mar 11, 2013 #3

    drewdin

    drewdin

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    Thanks for the quick response, ill look into insulation for the duct, do you recommend any specific type?
     
  4. Mar 11, 2013 #4

    kok328

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    Not sure what your intent is but, you can purchase pre-insulated duct at the big-box stores.
    This is your best bet against warm/moist air condensating in the exhaust duct but, it still happens. The shorter the run, the better.
     
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  5. Mar 11, 2013 #5

    drewdin

    drewdin

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    Thanks, ill look into it when i get there. I dont really have any intent, i was just poking around the attic and i noticed that there was just some flexible ductwork and was curious if there was any way to improve or prevent any unwanted anything.

    My friend always tells me that pre-mature upgrades are the root of all evil, i have not found any evil yet....
     
  6. Mar 11, 2013 #6

    nealtw

    nealtw

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    If you get clumbsy and put your foot thru the ceiling while up there, he would be right.
     
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  7. Nov 28, 2013 #7

    pstrick

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    My bathroom exhaust duct is positioned directly flush with the screen of my gable vent in the center. Reading this thread I am thinking about insulating the ducting.
    But is it okay for the duct to be in this location?

    Thanks

    IMG_4420.jpg
     
  8. Nov 29, 2013 #8

    nealtw

    nealtw

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    pstric; Welcome to the site, any time air is coming in the vent it will bring that moisture with it. It would be better to be some distance from the vent. Thru the roof wouyld be best but sideways away from the vent would likely be better than that.
     
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  9. Nov 29, 2013 #9

    Drywallinfo

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    You can insulate this pipe with a few cans of expanding foam. A rigid foam like this will not absorb any moisture should it seep out at a joint or seam and will in fact seal it in. This will work well with a shorter run. For a very long run it might be impractical. See http://www.drywallinfo.com/drywall-mold-removal.html for a pic of this.
     
    Last edited: Nov 29, 2013
  10. Dec 8, 2013 #10

    pstrick

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    Thanks for the input- pretty much what I was thinking. The "handyman" who did the job originally just kind of rested the 4" pipe next to the gable, which meant nearly everything blew right into the attic. I did the job you see in the picture to temporize until I get someone to finish the job right.
     
  11. Dec 8, 2013 #11

    havasu

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    Since I've been having a bout with wasps flying down the bathroom vent tube, I punched a hole in the stucco 4' below the gable vent and installed a louvered flap, commonly used in dryer vents, and it works slick with discharging moisture from the bathroom.
     
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  12. Jan 30, 2014 #12

    nealtw

    nealtw

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    Do a little research, mold kills people and houses.
     
  13. Feb 4, 2014 #13

    drewdin

    drewdin

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    so i insulated the vent pipe last night, i learned that i suck at it. Its done but if i posted a picture of my wrapping job you all would laugh.
     
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  14. Feb 4, 2014 #14

    oldognewtrick

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    Hey, we've all had moments when we were glad no one was there with a camera, it happens, we're human.
     

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