Moving Shower - Vent Issue?

[Tee Jay]

I've scoured the forums but can't quite find an answer to what I am trying to do. Here is what is currently there, and what I am trying to do. I have removed an old corner shower and am putting in a linear Schluter drain along the wall. I have attached actual pictures of the space that show what the numbers 1, 2, 3 line up with in the actual space.

What I am struggling with is the vent. Right now, I guess it would be wet vented with the sink. Or maybe not, this is from 30 years ago so probably okay for that time but maybe not now. There is no room to move the wye (labeled 2) back closer to the vertical drain (labeled 1). So in the desired layout, I would need to add a sanitary tee to the vertical drain, and then a long sweep 90 to carry onto the sink. In this layout I now have an s-drain for the shower.

 

[Reach4]

See https://winnipeg.ca/ppd/Documents/Brochures/Plumbing-Installations.pdf (guessing similar plumbing rules).
Looks like your 2-inch shower trap arm can be up to 8 ft long, so I think you would be ok with your "desired layout".

 

[Sponsor]

 

[Tee Jay]

So the inspector came out today and didn't love my executed desired layout and I'm not sure the best way of fixing it. I am hoping someone has a suggestion that will work.

The issue that I have is that the santee 90 combo that I put in puts the takeoff arm for the shower very low to where the trap would be below the ceiling at 1/4" foot slope. I had raised it up slightly with 2 45s but the inspector said that has created an s-vent.

The shower is wet vented by the sinks connected with a 2" street elbow at the top of the santee (connects to the 1 1/2" sink drain/vent) so I need a way to make this shorter so that santee arm comes out higher. I could go right from the santee to a 1 1/2" elbow instead of a 2, and I currently have an inch under the trap but that still doesn't get enough height. Any other ideas on how to get this higher and still wet vented through the existing sink drain?

 

[wwhitney]

A little terminology: combo means wye plus 45, typically as a single fitting. That's different from a san-tee; they both have "tee" connectivity, but the combo has more sweep (larger radius bend) on the side inlet.

The inspector is correct, the picture shown violates the trap weir rule. From the point where the2" shower drain hits the lav drain (the san-tee in your photo), going upstream towards the shower trap, the shower trap arm can rise no more than 2" total (while rising at least 1/4" per foot).

I see 3 options, each starting from where the lav drain emerges through that joist and going downstream:

a) A 1-1/2" street 45, a 2x1-1/2x2 san-tee with the barrel 45 off plumb and the shower drain coming into the side, and then a 2" (maybe street) 45. If the allowable 2" rise to the shower trap gets your trap high enough, you're good.

b) A 2" combo on the horizontal, then a street 2" quarter bend. The straight inlet gets a 2x1-1/2" bushing for the lav drain, and the side inlet gets the shower drain. The question is whether with the ide inlet of the combo against the joint, the 2" quarter bend outlet goes past your 2" stack.

c) I don't know if this part exists in ABS, but if you can find a 2x2x2x2 san-tee with side inlet (confirming the side inlet has the same curvature as a regular san-tee), then you could plug the top entry and bring the two drains into the side entries. There's some question of whether horizontal wet venting between the two side inlets is allowed, but I don't see why it shouldn't be.

Cheers, Wayne

 

[Tee Jay]

I'm going to mock up option a as that seems to be the best for giving me the height. B doesn't work as I don't have the room for the combo on the horizontal unless it is on the other side of the joist.

Just to confirm, this is what you were describing. This should give me the height that I need.

I couldn't find a 2x1-1/2x2 san-tee so I will need to use a 2 to 1 1/2 bushing on the top of the san-tee to get the 1-1/2" street 45.

 

[wwhitney]

Yes, that is (a) and should be an allowable horizontal wet vent. [Someone could complain about the short vertical section caused by the upstream 45, but I don't see that as an issue.]

Cheers, Wayne