Tie in for basement bathroom

Hello all,

DYI project for basement. I'd like to meet 2012 IPC code for this (town uses this). I've done many plumbing and electrical projects for 30 years. Some past work has been permitted when it was part of a larger permitted project.

Would anyone please comment on the following plan? The horizontal 4" waste is below slab. The lav is 12' total left and around a corner coming forward from the 3" vertical. The 1.5" horizontal vent will be in the ceiling joists. There will be a 4" check-valve downstream in an unfinished room as required by the town. Hopefully there's enough detail.

Thank you in advance,
Bill

Hi, this is a document from a canadian town, eventually it can help: http://winnipeg.ca/ppd/Documents/Brochures/Plumbing-Installations.pdf

Thank you. That is an excellent document. I suspect by your suggesting that this document can help me that there is something wrong that this document will show me, which I appreciate. Otherwise you would have said "looks good".

I have been suspect of the 2" trap downstream of the toilet, except that the toilet is not part of the wet vent. The trap is wet vented by less than a foot of the main line. Being a 4" wet vent for the 2" trap, I believed this to be acceptable.

Bill

I'm not a pro. This document helped me a lot in the past.
What is lav?

just some thoughts...
see wet venting page 10 in the Winnipeg doc, wc should be connected downstream of all other fixtures.
I think even only 1' of wet vent before the tub trap, you still have the waste of 2 wcs (one from upstairs?) in this 1' portion.
Would you have enough room to connect the tub trap to the vertical 2" vent or to the 45 degree portion of this 2" vent (where there is a "b" above the 4").
Maybe in the basement a 3" wc instead of 4" would help a little, and connected after the tub trap.
Any possibility to connect the lav to the vertical 3"(have to use a fernco somewhere on this 3" or replace underslab where it's written "4" existing").
you can put a plug on the tub when not in use (bad solution)

Thank you for your reply. The room is 5'9" x 5' with 4'x1' taken out of the corner for the 3" vertical drop. The tub was planned for the 5' wall making it's drain farthest downstream.
The tub can be turned 90* putting the drain up 4' allowing the wc to wye in after the tub but that's not needed. A 5' wall needs to be added at the head of the tub for the fixtures. This wall can now house a 1.5" vent for the tub.
Having busted up the concrete to firm up these plans, I learned the 4" pipe moves 1" per foot toward the planned trap location so there was 9" less to work with between the trap and wye. The trap would have to come off the wye, turn to the drain and hit the 4" pipe to line up the vertical connection to the drain.
The 4" pipe is sitting on a footing just past the trap so I now know doing anything further downstream won't be possible without tearing up more floor. That drove the design change to turn the tub.
I can change the wc to 3" and now wet vent to the 4" main - I cannot vent the wc into the 3" wc pipe without going horizontal to the wall but I can tie it in downstream of the vent into the 4" pipe. The lav/basin and tub can now be dry vented.
I'll see if I can make a better drawing - not my strong point.

Thanks again,
Bill

sorry I'm not sure to visualize all of what you're describing, maybe because I'm french and english is not my native language...

I don't see the following things in your plan:

- a clothe washer drain (should be 2" per code, and I now remember I was told by several plumbers it should be connected downstream of everything (at least for 2 basements I have done)... I think it's to avoid soap foaming in the tub or whatever).

- a backwater valve (required where I live in Canada)

- an emergency floor drain (should be 3")

what does "lav" mean in your plan?

Lavatory or sink...

I've come up with the following simpler plan. The left wye 2" to the wall, changing to 1.5" going horizontally for the the lav and the lav vent above 42". Each will tie in with a san tee into the vertical 2" vent.

The tub is vented after the trap and that continues and wye's into the 3" wc pipe. This vent will require a 2x6 wall but the plumbing will now be easier. That will san tee horizontally at 42" into the vertical 2" vent.

Regarding back water valve, I'm using a Canplas BWV - the one with the clear top - normally open.
This room was a 3-car garage that was walled in. It has a sump pit and pump so a floor drain isn't needed.

Thanks for you comments - I really appreciate them.

Bill

I'll comment, I'd like to know, what is the slope of the 4" drain ?

If it's ok with the slope of the 4" drain, and since the tub now has its own vent, you can connect the 3" toilet to the 4" drain closer to this toilet (before the wall). This will avoid the sharp turn (tub trap to the 2").

Also if you keep it like this there's a sharp turn on the 3" drain of the toilet, you can use two 22.5 instead of the 45 turn.

The slope of the 4" drain isn't great. Because of settling, the 2nd section of cast iron was very close to level. Having cut out most of the level section, there is now an even drop from each cast iron to PVC connection. It's about 1 1/4" over the 5 1/2'. I'm happy that the almost level section is removed.

As it turned out, the WC 3" is a straight pipe from the slow 90 bend to the 4x4x3 wye with an 1/8th bend on the wye. The 3x3x2 wye in that straight 3" pipe worked perfectly from the tub as it was a straight pipe from the trap to that wye. It might have been more difficult to connect the WC ahead of the tub and keep the 40" required distance from the vertical to horizontal 3" to 4" wye/cleanout.

Thank you,
Bill

Your WC/toilet should have a distinct vent. I am a UPC person, and the IPC seems more lenient as far as vents, but the drawing you have done doesn't look good to me on either code because I don't see the vent. Isometric drawings are much easier to see what is happening. BTW, what program did you use to paint up the sketches?

If the WC is not properly vented, the negative pressure created when the upstream fixtures flush(upstairs), could cause suction on the lower floor WC trap. Modern toilet trapways are very susceptible to minor pressure variations.