Basement Vent Rough-in - Standing Water

[Chris Tjoumas]

Hi everyone,

I'm starting to finish my basement and I have rough-ins in my basement from the builder; the toilet drain pipe, sink drain pipe and close by coming through the ceiling / upstairs is a capped 1 1/2" pipe which I am assuming is the vent pipe to tie everything in. The placement of the vent pipe was a bit outside of where the bathroom is, so I had to cut it and extend it a couple of feet over into the bathroom wall (currently just framed). When I cut the pipe to remove the cap, I was surprised by quite a bit of water that dumped out. It wasn't a ton of water, but it was a bit (maybe 1/4 or even 1/2 gallon? But I'm just wildly guessing). I thought maybe this has been condensation build up over the 6 years since the house was built. However, when I extended the pipe into the wall and capped it, I came back to remove the cap and about a cup or two of water came out when I removed it. Is this normal or a sign that there is some issue somewhere? I tried researching a bit to see if water will flow into a vent pipe like this but couldn't really find anything. I know once this is connected to the drain it will flow out, but not sure if this is normal or not...

Thanks!

Chris

 

[Tuttles Revenge]

Its likely connected to the rest of your plumbing and therefore a wet environment. We typically don't dead end vent connections for this reason. How much condensation depends on a list of factors too long to type out, but mostly on how moist and warm the vent is.. ie warm shower or laundry water will make more moist conditions.

This illustrates clearly why vent systems need to be connected and not have bellies in them.

 

[Sponsor]

 

[Chris Tjoumas]

Its likely connected to the rest of your plumbing and therefore a wet environment. We typically don't dead end vent connections for this reason. How much condensation depends on a list of factors too long to type out, but mostly on how moist and warm the vent is.. ie warm shower or laundry water will make more moist conditions.

This illustrates clearly why vent systems need to be connected and not have bellies in them.

Ok, thanks. If I understand correctly, this is most likely fine as it is (should be) the rough-in they left for when the basement bathroom is completed and that is tied into the drain that is capped in the floor at the moment.

 

[John Gayewski]

Ok, thanks. If I understand correctly, this is most likely fine as it is (should be) the rough-in they left for when the basement bathroom is completed and that is tied into the drain that is capped in the floor at the moment.

Yes. A lot of water can build up in vent systems. I recently added onto a house where the new plumbing hasn't been used or hooked up to the water yet. There is a steam on water at the bottom of that piping flowing through the sewer. It's a tiny stream but would add up to a lot if it were trapped.

 

[Chris Tjoumas]

Awesome, thanks to both of you for the info/confirmation!