I am remodeling our laundry room and I need some assistance correcting the previous owners plumbing work. I specifically have a question about using a circuit vent between a standpipe and a sink.

I am in Wisconsin and it is a basement laundry room and I have a septic system.

Please see link for a crude diagram of the way it is currently, a proposed circuit vent, and proposed individual vents.

[drive.google.com]

Yes the current is a wet vent, and not one that Wisconsin allows. This was done by the previous owner, who I am really beginning to hate (I have owned the house for 10 years). I should also point out that since this a basement, there are no other fixtures off that vertical stack, nothing above but a roof vent.

Due to room layout constraints I cannot just put another Sani-Tee on the stack. I have to to take care of all of this on one branch. Looking at Wisconsin code, it would seem that while a wet vent is not allowed in this scenario, a circuit vent would be. I really do not want to have to run a vent for both if I can avoid it.

[docs.legis.wisconsin.gov]


I would appreciate any advice. Thank you.



Edited 3 times.

your standpipe is not vented in any of the pictures. i would go with #3. just use a double san tee where the arrow saying 2 inch is pointing. use a 2 inch full size double san tee with a reducer to 1 1/2 in the top (vent). get a cleanout in there somewhere.

I am not sure if I follow Packy, where would the other side of that double go? It does not make any sense to send it over to that vertical vent...

Something like this? [drive.google.com]

you got it correct now. get a cleanout in the 2 inch somewhere.

Packy, wouldn't he be better off stacking a pair of sanitary tees, lower one for washer, upper for sink, instead of double sanitary? Put the 2" cleanout above the upper sanitary tee and then reduce to 1½" for vent.

steve, i don't have a problem with double san tees but stacking would be better.

Thanks Packy. I was making it way too complicated. Steve I appreciate your input too but I don't have the vertical space for stacked. It is going to have to be a double which actually works out perfectly for both washer box height and it's code requirements and an 18" stub out for my sink cabinet requirements.

Can I put the cleanout on top of the double and make it accessible from the other side of the wall?



Edited 1 times.

you can put the cleanout above but keep it 2 inch and reduce to 1 1/2 at the top of the cleanout.

Great. Thanks Packy.

Packy, I got this knocked on Saturday. Put the 2" cleanout on top of the double then reduced to 1.5" for vent going up. Wife has been doing laundry all day, everything looks and works great. Thanks again.