Correcting a dry fit

[anonimoose]

Hello! I am shrinking a bathroom that had a really messed up plumbing situation (like an unvented shower) that I'm trying to improve. I'm in NY State. I did an initial dry fit, then more research, and realized I did a few things wrong (like trying to horizontal vent the shower to an old unused vent below the flood level rim). This image has notes about my proposed fixes. Would this work? Questions I've struggled with:

- I think the wc has to be furthest downstream, which is why I'm proposing looping the shower upstream (with a downward slope...there is space for that).
- I need to add a cleanout on the shower drain b/c it's more than 135 degrees of horizontal turns, right?
- These would all be wet vented off a 2" vent that is off to the right by the lav. Is 2" big enough? I've seen conflicting info here.
- Is there any problem with using a 3x3x2 combo for the shower drain into the main line horizontal to horizontal? Hard to see but I've got a 2x3 increaser upstream after the 90 degree bend in the lav drain.
- And any issue with the 3x3 wye horizontal to horizontal for the wc, after the shower drain?

Thanks in advance for the help!

 

[Tuttles Revenge]

Looks like a well designed horizontal wet vent system. Toilet most downstream, shower trap arm under 60" and lav(s) being the dry vent.

 

[Sponsor]

 

[wwhitney]

New York state uses the IPC, which allows:

- The WC to be anywhere on the wet vent, it doesn't have to be the last fixture.
- A 1-1/2" dry vent on the lav
- A wet vent carrying 1 DFU (a single lav) to be 1-1/2".
- A wet vent carry 2-4 DFU to be 2".

I suggest you connect the shower downstream most, you can orient the u-bend of its trap to be parallel to the outside wall, and the outlet elbow turned 45 degrees relative to that, then it could hit a LT90 to enter into a horizontal wye on the 3" line, just upstream of where the 3" branch drain turns downward. At least, it appears to me that geometry would fit. If it's tight, the most compact pattern there would be a street 3x3x2 wye into a 3" quarter bend where the 3" branch drain turns downward.

Cheers, Wayne

 

[wwhitney]

Also, be aware that if your dry fit has certain fittings in precise locations, you will need to cut some new lengths of pipe 1/4" to 3/4" longer when you do the glue up. That's because plastic DWV is an interference fit, so when you glue up the joint and push the pipe home, it will insert deeper than you can do it dry.

Cheers, Wayne

 

[anonimoose]

Also, be aware that if your dry fit has certain fittings in precise locations, you will need to cut some new lengths of pipe 1/4" to 3/4" longer when you do the glue up. That's because plastic DWV is an interference fit, so when you glue up the joint and push the pipe home, it will insert deeper than you can do it dry.

Cheers, Wayne

Thank you for both comments, this is super helpful!!

 

[anonimoose]

I ended up doing a dry fit before this message was approved. It looks like this. Unless y'all see problems with this I might keep it as-is rather than try again, though I appreciate the suggestion (and confirmation that NY doesn't require wc last).

Do I have to do a long sweep on that 90 bend on the shower before I connect it via combo to the 3"? Having a long sweep + a cleanout there mean that it's a little bit wide and I start to get concerned about there being enough distance between the wall and the main line.

 

[Michael Young]

Hello! I am shrinking a bathroom that had a really messed up plumbing situation (like an unvented shower) that I'm trying to improve. I'm in NY State. I did an initial dry fit, then more research, and realized I did a few things wrong (like trying to horizontal vent the shower to an old unused vent below the flood level rim). This image has notes about my proposed fixes. Would this work? Questions I've struggled with:

- I think the wc has to be furthest downstream, which is why I'm proposing looping the shower upstream (with a downward slope...there is space for that).
- I need to add a cleanout on the shower drain b/c it's more than 135 degrees of horizontal turns, right?
- These would all be wet vented off a 2" vent that is off to the right by the lav. Is 2" big enough? I've seen conflicting info here.
- Is there any problem with using a 3x3x2 combo for the shower drain into the main line horizontal to horizontal? Hard to see but I've got a 2x3 increaser upstream after the 90 degree bend in the lav drain.
- And any issue with the 3x3 wye horizontal to horizontal for the wc, after the shower drain?

Thanks in advance for the help!

What you have will work just fine. I don't know that I'd reduce down to 2" for the lavatory. If you have room, take 3" the whole way. That'll allow you to put a full-port cleanout under the cabinet for future service. (if you have a 3" cleanout tee under the lavatory, you can service the entire bathroom without having to pull the toilet)