Condensation on an ABS vent pipe in bathroom

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jgraf
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Condensation on an ABS vent pipe in bathroom

Post by jgraf » Fri Nov 22, 2019 12:44 am

Hello there, I'll try to explain my problem as best as i can, i live in Manitoba which we all know can have some pretty terrible weather. Over the last week or week and a half i noticed a lot of moisture or condensation on an ABS pipe that comes out of the wall and into the cabinet of my sink in the bathroom. it looks like a 1 inch or 1 and 1/4 inch pipe. 1st question is this a vent pipe? and second question where is all this moisture coming from? I had a plumber open the wall and spray foam where the elbow joint is right at the ceiling and he also went in the attic and sealed around the main stack. Im pretty stumped here and the issue doesnt seem to be going away. Any ideas as to what i can do?

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Aaron
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Re: Condensation on an ABS vent pipe in bathroom

Post by Aaron » Fri Nov 22, 2019 1:19 am

If you touch the pipe, is it really cold?

jgraf
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Fri Nov 22, 2019 1:49 am

Not like super cold but yes it's cold

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Shannon
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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Fri Nov 22, 2019 6:54 am

I'm sure its a vent. If its been pretty cold outside the air in the pipe is cold and the warm air of the house is causing condensation on the cold pipe. This would be my guess. Is this an issue you have never noticed before? Maybe your humidity in the house is higher then usual?
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jgraf
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Fri Nov 22, 2019 7:08 am

Never noticed it till the water pooled in the basement, the humidity has been pretty normal in the house nothing more then usual. I thought maybe the stack isnt sealed off properly or something at the attic. The amount of moisture on the pipe too is quite a lot. Would insulating the pipe do anything?

jgraf
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Fri Nov 22, 2019 7:36 am

Another question would be why does it.clear up.when it's nice out?.

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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Sat Nov 23, 2019 6:06 am

Hi there, would it be possible if a toilet in a different bathroom was leaking would that be enough to cause condensation on the pipe in the other bathroom?? Just racking my brain here trying to figure out what it could possibly be

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Aaron
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Re: Condensation on an ABS vent pipe in bathroom

Post by Aaron » Sat Nov 23, 2019 2:19 pm

It's weird to say the least. ABS doesn't conduct heat or cold very well anyway, and even if the pipe carried ice cold water it's hard to imagine it being so cold that condensation would form on it?

I think the moisture you're getting may not be condensation but a small leak of some sort running along the pipe.

The weather could be a factor but correlation is not necessarily causation. I think you just have to chase the pipe up and see where that water is coming from? That's the only advice I can offer unfortunately!

Intermittent trouble is the worst, too. :(

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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Sat Nov 23, 2019 4:53 pm

Aaron wrote:
Sat Nov 23, 2019 2:19 pm
It's weird to say the least. ABS doesn't conduct heat or cold very well anyway, and even if the pipe carried ice cold water it's hard to imagine it being so cold that condensation would form on it?

I think the moisture you're getting may not be condensation but a small leak of some sort running along the pipe.

The weather could be a factor but correlation is not necessarily causation. I think you just have to chase the pipe up and see where that water is coming from? That's the only advice I can offer unfortunately!

Intermittent trouble is the worst, too. :(
So even if it is intermittent theres a possibility it's still a leak? The pipe will totally dry up some days to not even a bead of water which is why I find it hard to believe. I'm leaning more towards a humidity issue and maybe wrap the pipes in the attic with some sort insulation

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Re: Condensation on an ABS vent pipe in bathroom

Post by Aaron » Sat Nov 23, 2019 11:14 pm

jgraf wrote:
Sat Nov 23, 2019 4:53 pm
So even if it is intermittent theres a possibility it's still a leak? The pipe will totally dry up some days to not even a bead of water which is why I find it hard to believe. I'm leaning more towards a humidity issue and maybe wrap the pipes in the attic with some sort insulation
Sure, give it a go. Your guess is as good as mine, honestly.

Sort of a silly experiment but I wonder if you can duplicate the problem? Does a glass of ice water have condensation any time the pipe does? Because there should be no circumstances where the pipe would have condensation and not the glass, which could rule out condensation.

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Shannon
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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Sun Nov 24, 2019 9:40 am

Ya this is a weird one if it is actually condensation. Sorry at this time I have nothing else coming to mind . let us know if you figure something out.
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Sun Nov 24, 2019 9:44 am

Yeah it is weird I've been talking to a guy local to where i am and he says to wrap the pipe in the attic and run the HRV system more to help keep the air moving. I'll post back with results in a few days thanks for your help

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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Sun Nov 24, 2019 9:57 am

Seems odd that the pipe would be cold enough all the way down in the basement to allow condensation .
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Sun Nov 24, 2019 10:00 am

Shannon wrote:
Sun Nov 24, 2019 9:57 am
Seems odd that the pipe would be cold enough all the way down in the basement to allow condensation .
No, it's the pipe in the upstairs bathroom sorry, what I meant was it drips down following the pipe into the basement so it builds up in the upstairs then kinda drips down following the pipe. Sorry for the confusion.

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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Sun Nov 24, 2019 4:44 pm

OH I see now. Ok I can see that pipe maybe being cold enough if its only 8' or so from cold attic and end of open pipe on roof.
Yup ,try wrapping the pipe with insulation in attic and see what happens
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Sun Nov 24, 2019 4:52 pm

Shannon wrote:
Sun Nov 24, 2019 4:44 pm
OH I see now. Ok I can see that pipe maybe being cold enough if its only 8' or so from cold attic and end of open pipe on roof.
Yup ,try wrapping the pipe with insulation in attic and see what happens
Yeah I've wrapped the pipe was a tight fit hopefully it did the job though and I'll continue to monitor...the stack on the roof itself is open should I be getting a cover or something maybe??

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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Sun Nov 24, 2019 5:07 pm

No the pipe up top does not get covered.
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Aaron
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Re: Condensation on an ABS vent pipe in bathroom

Post by Aaron » Sun Nov 24, 2019 11:09 pm

It's just odd to me that ABS pipe could get that cold. ABS doesn't conduct temperature that well, or so I thought. This is a very unusual situation if it's condensation.

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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Mon Nov 25, 2019 8:28 am

Aaron wrote:
Sun Nov 24, 2019 11:09 pm
It's just odd to me that ABS pipe could get that cold. ABS doesn't conduct temperature that well, or so I thought. This is a very unusual situation if it's condensation.
Yeah I find it really odd as well, like for example it's been hovering around zero Celsius here and the pipe is bone dry ...I'm waiting for a change in weather right now to see what happens. If it were a leak wouldn't it be constantly happening? Just seems really weird

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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Mon Nov 25, 2019 8:56 am

Maybe its just the right conditions at the right time causing it? Cold air in pipe and warm moist air in the bathroom
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Mon Nov 25, 2019 8:59 am

Yeah i guess that would be possible. I've been advised to run my air exhanger more often which I've been doing, I'll continue to monitor the situation but as of now it's dry

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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Sun Dec 08, 2019 9:00 pm

Hi there havent posted for a while as I had hoped the problem had fixed itself....I was wrong. So since my last post I had wrapped the vent stack in the attic with some insulation and I was waiting to see what happened when it got a little colder. Last night was finally a lot colder and this morning the pipe had frost on it right where it comes outta the wall. The humidity level in the house is low so I dont think it's that anymore. I was wondering what your guys thoughts would be? Wall not insulated properly? Thanks for your help.

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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Mon Dec 09, 2019 7:50 am

I see you never posted a picture of the pipe and situation , maybe that may help us?
It could just be that the pipe is cold in the wall and no insulation around it so the cold pipe frosts up on the warm side of the wall when the temps drop?
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Mon Dec 09, 2019 7:54 am

Shannon wrote:
Mon Dec 09, 2019 7:50 am
I see you never posted a picture of the pipe and situation , maybe that may help us?
It could just be that the pipe is cold in the wall and no insulation around it so the cold pipe frosts up on the warm side of the wall when the temps drop?
Image
Ok so I think I attached a picture hopefully it worked, it's from a few weeks ago but as of today the whole pipe that I can see under the sink is covered in frost. Would it be a good idea to open the wall and wrap that pipe in insulation?
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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Mon Dec 09, 2019 7:29 pm

ok so I will guess that it is just because the pipe is cold right in the other side of the drywall and then the warm air and lack of air flow in the cabinet allow moisture to condensate on the cold surface of the pipe. Insulating around this entire pipe may help but it may just frost up below the floor where you can’t see it? Not sure there is a perfect fix but I’m not sure that it is a huge deal either unless the pipe is really dripping moisture and causing moulding issues in the cabinet?
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Mon Dec 09, 2019 7:32 pm

Shannon wrote:
Mon Dec 09, 2019 7:29 pm
ok so I will guess that it is just because the pipe is cold right in the other side of the drywall and then the warm air and lack of air flow in the cabinet allow moisture to condensate on the cold surface of the pipe. Insulating around this entire pipe may help but it may just frost up below the floor where you can’t see it? Not sure there is a perfect fix but I’m not sure that it is a huge deal either unless the pipe is really dripping moisture and causing moulding issues in the cabinet?
Whats actually happening is it follows the pipe into the basement where it pools down there ..tried spray foaming the bottom part of the cabinet but it seems to make it's way through

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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Tue Dec 10, 2019 7:43 am

Well I would wrap pipe insulation around it or cover it in bat insulation and cover it in and see if that stops it.
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Tue Dec 10, 2019 6:38 pm

Shannon wrote:
Tue Dec 10, 2019 7:43 am
Well I would wrap pipe insulation around it or cover it in bat insulation and cover it in and see if that stops it.
So we cut the wall open and that's what it looks like...everything looks like its insulated well but the pipe is really cold to the touch. Figure just wrapping the pipe will fix the problem??
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Re: Condensation on an ABS vent pipe in bathroom

Post by Shannon » Tue Dec 10, 2019 7:55 pm

I ment covering the exposed pipe in cabinet. The pipe is in a cold zone (in wall) nothing you can do with that area
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Re: Condensation on an ABS vent pipe in bathroom

Post by jgraf » Wed Dec 11, 2019 8:01 am

Shannon wrote:
Tue Dec 10, 2019 7:55 pm
I ment covering the exposed pipe in cabinet. The pipe is in a cold zone (in wall) nothing you can do with that area
Yeah, I wanted to make sure behind the wall was ok, seems like the only major frost build up is where it comes into the vanity. You think if I wrapped the pipe in the vanity and then wrapped the pipe in the basement that might stop it from at least dripping down there? When it's all frosted up doesnt seem to be a huge problem obviously it's just when the pipe starts to thaw out a bit

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