Vent Pipe on Outside of Exterior Wall

[RobWilson]

Hi all!

I am planning on installing a bathroom in my basement, I live in Maine (IPC code, I think). I have easy access to the main stack to the septic system but venting the drains (and up flush toilet) is going to be difficult. After hours of research I am totally lost on when wet venting is allow so I'm hoping I can dry vent this bathroom without destroying the drywall on the first and second floor.

I can (fairly) easily run a vent pipe up from the basement through the exterior wall and up about 25' outside the house ending above the roof line.

My question is are there any plumbing codes that prevent me from running a vent pipe OUTSIDE the exterior wall?

Thanks a bunch guys!!
Rob

 

[Jeff H Young]

None that I know of prohibit an exposed vent pipe that runs sufficiently high enough perhaps in cold weather there is something

 

[Sponsor]

 

[RobWilson]

None that I know of prohibit an exposed vent pipe that runs sufficiently high enough perhaps in cold weather there is something

Thank you for your response! The only thing that I have seen anyone online say is that it has the potential to frost up inside the pipe and block the flow. This seems pretty unlikely to me but I'm thinking I might upsize the diameter to like 2". I have a radon vent pipe (two actually, one for a under foundation system and one for a water system) that runs up the side of the house. These never frosted up so this seems like the same thing to me.

Thanks again!

 

[John Gayewski]

You can run pipe outside of walls in any case. Just some clearance issues with things that get hot or the place it terminates is specified.

 

[RobWilson]

You can run pipe outside of walls in any case. Just some clearance issues with things that get hot or the place it terminates is specified.

Thanks! I think this is probably the best bet instead of doing some shady "wet venting".

 

[Jeff H Young]

Personaly I would keep it min 2 inch If I lived in some cold freezing climate Id follow regional practice .( Im just use to 2 inch vents because our code is strictor no toilets here get a 11/2" vent)

 

[RobWilson]

Personaly I would keep it min 2 inch If I lived in some cold freezing climate Id follow regional practice .( Im just use to 2 inch vents because our code is strictor no toilets here get a 11/2" vent)

I think I'll take that advice. I don't see any harm in going 2" over 1.5". I'd rather over build then under build and have to do it again, that's for sure!

 

[Jeff H Young]

I think I'll take that advice. I don't see any harm in going 2" over 1.5". I'd rather over build then under build and have to do it again, that's for sure!

If you can get some local advice it might help only thing is is the frost Plastic needs painting as well

 

[RobWilson]

If you can get some local advice it might help only thing is is the frost Plastic needs painting as well

Yes as I have looked more into the IPC it looks like that this is acceptable however the 97.5% design temperature where I live is -1 degrees F. Since that is below 0 degrees F I need to use a minimum of a 3" vent when it is outside the house. PLUS I need to use heat or insulation to prevent frost. Any suggestions on exterior insulation for 3" PVC? I was thinking the closed cell black stuff but finding it in 3" is pretty hard.

 

[Jeff H Young]

Rob , glad you checked thats why I brought up your weather. Im very aware of increased vent pipe sizes where penetrating roof running exposed outside house might require that too. the insulation kinda makes the job worse there might be product that looks clean just for this Sorry but I dont know anything beyond what I mentioned but let us know how you solve or come back with other questions !