Insulate the bathroom vent hose to outside?

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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
 
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.
 
Thanks for the quick response, ill look into insulation for the duct, do you recommend any specific type?
 
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.
 
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....
 
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
 
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.
 
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.
 
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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.

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.
 
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.
 
[FONT=&quot]I've used this method for customers and it works just fine. Not enough moisture to really affect attic. Most vents through wall or roof are lousy installs resulting in rain entering unit or bugs getting into the attic. A little moisture is better in my opinion and has less chance of clogging rather than having long flex tubes running all over the attic and getting smashed by people pulling maintenance or just doing stuff in the attic. [/FONT]

Do a little research, mold kills people and houses.
 
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.
 
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.

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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