[tom_poconos]

Hi, I've been planning a bathroom drainage system. The bathroom will have a wall-hung toilet, a sink and shower. I'm looking for any feedback on potential issues or code violations.

Couple of notes:

- The wall hung toilet's 3" outlet will be pitched at 45 degrees - this is allowed per the installation manuals of the Toto and other brands of hung toilets.
- The 3" toilet sanitary tee fitting has a 2" inlet on the side for the shared shower/sink drain. Not sure if this is allowed but it seems like the perfect fitting to connect lines at the corner of the room.
- Any fittings I didn't point out are just regular tees or short elbows for venting.

Any thoughts would be greatly appreciated!

 

[TheEplumber]

I see some possible cost savings if you wet vent the shower and lav- as long as you don't exceed trap lengths.

I would check with your plumbing inspector about the side inlet san tee. I would not be allowed to do that...

Also check the minimum size of vent required for the toilet.

Also, sanitary tees do not go on their backs. You need a combination wye&45- AKA combie, or long turn tee-wye

 

[tom_poconos]

I see some possible cost savings if you wet vent the shower and lav- as long as you don't exceed trap lengths.

I would check with your plumbing inspector about the side inlet san tee. I would not be allowed to do that...

Also check the minimum size of vent required for the toilet.

Also, sanitary tees do not go on their backs. You need a combination wye&45- AKA combie, or long turn tee-wye

Thanks for your feedback. I have a couple of followups if you don't mind:

• Here is the 3" sanitary-tee with 2" side inlet. If I have read correctly, it is IPC compliant (Philly uses IPC) to use this inlet as long as the 2" inlet sweeps down on the fitting (IPC, fitting photo). How would you design a corner connection if this fitting is illegal where you are? -- I don't want to use something that is legal but potentially problematic.
• You mention I had a sanitary tee on its back - which one? Was it the shower?

I will recheck the toilet vent minimum size - cheers.

 

[tom_poconos]

For some reason I couldn't edit my last post (I swear I've been able to in the past...) - sorry - is this (attached) how you would implement a complaint alternative to the sanitary tee with side inlet?

 

[huesmann]

Can I just compliment you on your nice sketches?

 

[Ghostmaker]

You can use your weird san tee . Run 2 inch to the lav sink. Use a wye and 45 on its back to pick up the lav. Vent the lav with 1.5 inch as drawn. Just make sure when that vent turns horizontal it is 6 inches above the flood level rim of the lav sink. (normally 42 inch to center off floor) Continue with 2 inch to shower you need not vent the shower as long as the trap for the shower is within 8 foot of the lav wet vent.


You can also do it the second way if you so desire. But follow the rest of the instructions above.


Make sure you get your toilets wall hung bracket properly installed. They require serious structural reinforcement.

 

[tom_poconos]

I'm going to ditch the fancy sanitary tee with side inlet - even though it simplifies things I think it might be too difficult to fit it at the very corner of the stud work. So I'll go with a standard 3" sanitary tee and a wye beneath it for the shower/lav. Is that ok? Could the toilet get siphoned by the shower/sink?

Run 2 inch to the lav sink.

Is this to wet vent the shower? If I choose to vent the shower as per the drawing, I can keep the 1-1/2" lav drain, right?

Make sure you get your toilets wall hung bracket properly installed. They require serious structural reinforcement.

I'm going to reinforce that thing like a goddamn panzer tank :hammer:

See attached new draft. Thanks!

 

[TheEplumber]

For some reason I couldn't edit my last post (I swear I've been able to in the past...) - sorry - is this (attached) how you would implement a complaint alternative to the sanitary tee with side inlet?

You have 30 minutes to edit a post once it goes up on the board. We have reasons for this too, but that's a seperate thread....

My inspectors allow me to use the side inlet tee but the 2" inlet needs to be a trap arm only. In your case it's shown used as a horizontal branch line. By definition- it's splitting hairs, but the inspectors usually win....:wink2:
Go with what Ghost says since he gets paid to interpret IPC.
I would use something very similar to your picture.

 

[Old Thomas]

You are connecting to a horizontal pipe. If the connection is to the top of the horizontal pipe, a sanitary tee is ok. If the connection is to the side of the horizontal pipe, it needs a wye and a 45. As the connection is rotated from the top to the side, it changes from a sanitary tee to a wye at the 45 degree point.
You need one full sized vent stack. If you have another that is full sized, ok. If not, your vent must be 3“ all the way up, not necked down to a smaller size.
Based on NY’s version of the IRC.

 

[Ghostmaker]

"Is this to wet vent the shower? If I choose to vent the shower as per the drawing, I can keep the 1-1/2" lav drain, right?"

The drain should be 2 inch, The vent on the lav can be 1.5 inch and you do not need the vent on the shower as long as the shower trap is within 8 foot of your lav connection to the drain.


Your last picture is also fine it is just using more venting than required. UNDER IPC

 

[tom_poconos]

The drain should be 2 inch

I'm seeing in most places that a 1.5" lav drain is fine, unless it's a double lav or a laundry lav. But to be safe I'll just go with 2" as you suggest, it makes no difference to me.

you do not need the vent on the shower as long as the shower trap is within 8 foot of your lav connection to the drain.

My rough estimate is the shower trap will be 5-7' away from the lav connection. So I could eliminate the shower vent -- but I don't know what type of fitting is compliant for this part. Would a 90 sweep elbow be fine?

Thank you

 

[Ghostmaker]

yes 90 fittings under 3" in size are legal to use in that posistion.