Back 2 back toilet vent question!

[jamesforyst]

Greetings everyone. I have a back 2 back toilets setup with a wall between both toilets. The drain runs parallel to the joists which runs parrallel to the toilets and perpendicular to the wall separating them. It would be convenient for me to run the vent between the two toilets in wall that separates them. Attached is the picture of the setup.

 

[Endo]

Why not this?

 

[Sponsor]

 

[BECplumbing]

Greetings everyone. I have a back 2 back toilets setup with a wall between both toilets. The drain runs parallel to the joists which runs parrallel to the toilets and perpendicular to the wall separating them. It would be convenient for me to run the vent between the two toilets in wall that separates them. Attached is the picture of the setup.

To run the vent between the toilets you need to use a double wye fitting. You don’t want to use a double San cross or a double fixture fitting because it will suck water out of the toilet on the opposite side

 

[jamesforyst]

Why not this?

View attachment 100667

The problem with this is that this is on the second floor. I have only about 10.5" of space to fit it. This is over a finished 1st floor.

 

[Reach4]

Greetings everyone. I have a back 2 back toilets setup with a wall between both toilets. The drain runs parallel to the joists which runs parrallel to the toilets and perpendicular to the wall separating them. It would be convenient for me to run the vent between the two toilets in wall that separates them. Attached is the picture of the setup.

If you are in an IPC area (bulk of TX) I think you would be OK. If you are in Austin, Houston, Dallas, San Antonio or FW, I think you are under UPC, and probably not ok.

Your drawing seems a little ambiguous to me. I think the 3 inch wye is in the horizontal plane, and not the vertical plane. I think the vent is vertical. Even if the wye is in the vertical plane, I am not sure. But that does not go along with your mounting a toilet on the floor and the long pipe being in the wall.

 

[Jeff H Young]

drawing has 2 views the second view confirms the wye conection is verticle to the closet flange. upc would require a horreizontal connection

 

[plumb1234]

Depending on your situation, you might have to build a soffit on the downstairs cieling.
Using a double fixture fitting would be the easiest, and you can have a street long sweep 90 glued into the double fixture fitting to turn horizontal immediately.

 

[jamesforyst]

I

drawing has 2 views the second view confirms the wye conection is verticle to the closet flange. upc would require a horreizontal connection

Yes, I agree. I came to the same conclusion on that. I placed the Y for the first toilet horizontal and connected a long sweep 90 3". I feel like I think I got the drains legal, I haven't seen an example exactly like this as far as the venting. Thanks.

 

[wwhitney]

Allowed under the IPC as horizontal wet venting.

Not allowed under the UPC. If, however, you moved the horizontal branch drain so didn't pass directly under the second WC, and rolled the wye so it was horizontal, then it would be allowed under the UPC as circuit venting.

Cheers, Wayne