I want to make sure my plumbing plan is code compliant

[Infinitysa]

My plan is to drain my double sink vanity into the 2” toilet vent. I live in Oregon, which is under UPC. I just want to make sure this looks up to snuff before I proceed. Thanks for the advice. Vent would be about 4 ft from WC. All very to horiz bends will use LT fittings.

Apologies for the drawing.

 

[Infinitysa]

Any help here? I think this is fine under UPC, but I am not sure if the wet vent section needs to be 3" or if 2 is sufficient. I am working with 2x4 walls, so I was hoping this design with a 2" wet vent would be okay.

 

[Sponsor]

 

[Jadnashua]

Generally, once a pipe is configured to be a vent, it cannot become a drain. Wet venting tends to only work on the horizontal when adding another drain...not vertical. Not positive, but I don't think that will pass.

 

[Infinitysa]

Oregon’s plumbing code allows for vertical wet venting. The relevant code is 908.1, which can be found here.
http://www.iapmo.org/2014 Oregon Plumbing Specialty Code/2014OregonPlumbingSpecialty_Ch09_Vents.pdf

It appears to me that the vertical wet vent works, as long as the pipe size is one size larger than the required drain size. Normally, people quote the required drain size of a double vanity be 2”, but when I look up under size requirements here
http://www.iapmo.org/2014 Oregon Pl...nPlumbingSpecialty_Ch07_Sanitary Drainage.pdf

In table 7-5, 1.5” vertical drains can handle 2 dfus, just not horizontal drains. Since my drain would be only vertical, then 2” would be one size greater than the required drain size.

Now, I am a total novice at this, so I may be completely off base, which is what I am trying to determine. I would call my inspectors office, but last time I had a question, it took them two weeks to return my call...

Thanks

 

[Terry]

It looks good to me with the 2".
UPC like to see a total of 3" through the roof, which can be done with
2 x 2"
1 x 1.5"
=
3"

 

[Infinitysa]

That is something I haven’t considered. I was going to hook up to the existing roof vent, which serviced the original bath (one shower, one WC, one lav). I am moving the bath to a new location, hence all new plumbing. I think the current vent is 2”. Is 3” for the whole house? The house has 4 vents currently, 2x2” and 2x1.5”

Also, thanks for the help!

 

[Terry]

The house has 4 vents currently, 2x2” and 2x1.5”

Plenty of vents going through the roof. You can run three bathrooms on a 2" vent assuming you have the others too.