Bathroom remodel- designed to CA 2019 plumbing code?

[jim pipe]

I’m relocating every fixture for a remodel and wanted to run my plan by you fine folks to polk holes before the long weekend of fun. I’m hoping to limit the rework during inspection, but more importantly have good flow. I’m on the 2nd floor connecting directly to existing 3” stack. The current stack has 3x3x1.5x1.5 wye, so need to cut off for 2” from bathtub and shower/ double lav. Clearance is fine in wall, but getting up into the floor joist was 14” wide and reduced to 12” for structure repair( sister joist). Main concerns are clean outs needed with 2nd floor exception or does 135 agg bend take priority. The other issue is all the wyes on the stack. Can’t fit fixture tee with width, so trying to stack shower (needing vent from top of stack) on top of wye +bend for tub that is vented (but needs lower elevation at stack due to long run). I will be running the 2 inch from the stack to show in floor joist to get elevation for ptrap and clearance from 3” for water closet. The 2” is vent from down stairs bathroom group, so can’t tie in. Will likely need to change angle since slopes backwards, so plan to cut as needed. Cheers!

 

[Jeff H Young]

cleanouts not required on upstairs. I've seen argument to this on trap arms and not sure on trap arms serving second floor.

 

[Sponsor]

 

[wwhitney]

As you've drawn it, the double lav can wet vent the shower. So you don't need the 2" vent over the 2" san-tee you show near the existing 3" stack. And if you do want to dry vent the shower instead of wet venting the shower, you'd need to run the shower drain separately from the lav drain. A trap arm needs to get vented (or is vented) before (dry vent) or as (wet vent) it joins another drain.

If you wanted, you could vent the whole bathroom with a single 2" vent at the double lav. An arrangement like the drawing below would work (green = 2", red = 3"), assuming it doesn't route a 3" line through a joist that you can't drill (but hopefully you could adjust the layout to avoid any joist drilling for 3" lines). A trap arm is limited to 42" for a 1-1/2" trap and 60" for a 2" trap, so I'm showing the tub trap as 2" for the extra length in case you need it. And I hope that 60" is enough; if not you could consider rerouting the lav drain as required to comply with that limit.

[The controlling rules for sizing are the trap arm length limits; a WC needs a 2" vent; a 2" wet vent can only carry 4 DFUs, so the wet vent gets upsized to 3" once it is carrying 2 lavs, the tub and the shower; and of course a WC needs a 3" drain.]

Oh, and with the 2" vent at the lav, you needn't continue the 3" stack through the roof (but you may if you wish), unless you need it for the aggregate vent area rule [Basically a house with up to 3 WCs needs either a 3" vent through the roof, or vents of at least as much area, e.g. (2) 2" and (1) 1.5" vent.]

Cheers, Wayne

 

[Jeff H Young]

Wayne has a nice plan .
I wouldn't be drilling out joists with 3-5/8 hole in middle of span .
Jim Pipe , plan works well too and easy on the framing it appears .
plus it has less horizontal venting which I prefer but either is good . I guess I'd boil it down to whichever is easier for you.

 

[jim pipe]

Thanks for looking at this Wayne! I should have said in my original post I’m working on 2x10 floor joist. Existing 3” runs below floor joist in drop ceiling, but my shower needs to be 8 inches higher to accommodate 2” ptrap and follow boring limits. My tub trap to vanity 2” is 7 ft, so got stuck there… my original plan had a horizontal vent behind tub running up wall, but was suggested I correct by moving 2” towards wall to correctly vent. I could try to get a 3 inch running back to tub, but then I need to cut into drop ceiling framing… I’ve reworked and drilled a few holes before I made it to this sketch. I look forward to getting it done and passing inspection.

 

[jim pipe]

Wayne has a nice plan .
I wouldn't be drilling out joists with 3 5/8 hole in middle of span .
Jim Pipe , plan works well too and easy on the framing it appears .
plus it has less horizontal venting which I prefer but either is good . I guess I'd boil it down to whichever is easier for you.

Thanks Jeff, I look forward to sending pictures of some finished work!

 

[wwhitney]

FWIW, I didn't follow the narrative closely enough.

If you'd like further advice or suggestions then please show the direction of the 2x10 floor joists on your floor plan, along with the region where there's a drop ceiling framed and some details on the drop ceiling. Also the location of 3" stack, WC and closest joists with some precision. And some distances for fall calculations.

Otherwise, best of luck.

Cheers, Wayne

 

[Jeff H Young]

jim pipe you might have a wall between the w/c and shower to bring a vent pipe up. you mentioned some issue with shower trap too low.

 

[jim pipe]

I’m glad Wayne mentioned the shower was wet vented in my drawing and the dfu difference. Another thing I should have mentioned was the shower will have 3 heads, so 4 dfu and with the double lav exceeding that limit on wet. I’m going to run a dry vent right after shower wye, by rolling wye at 45 to get a dry vent vertical in the wall as Jeff suggested. My field inspector was nice enough to take a look and said no issues. I need to isolate the downstairs vent, but see no issue adding test plug.

Is it crazy to add a clean out below fittings I will be adding to test on the stack? I could only find one out of the house and don’t want to test the whole system.

 

[wwhitney]

I’m glad Wayne mentioned the shower was wet vented in my drawing and the dfu difference. Another thing I should have mentioned was the shower will have 3 heads, so 4 dfu and with the double lav exceeding that limit on wet.

4 DFUs vs 2 DFUs for the shower only matters downstream of the shower; it doesn't affect upstream of the shower or the wet vent sizing. Your original drawing is still fine with the shower wet vented. And on my alternative drawing, it changes the wet vent between shower and WC from 6 DFU to 8 DFU, but that doesn't cause any sizing change; both require a 3" wet vent.

I’m going to run a dry vent right after shower wye

If you want to dry vent the shower, the dry vent has to come off the trap arm before the wye where the double lavs join the shower. If you put it after, the double lavs are still wet venting the shower, and it's just some sort of bonus relief vent that doesn't help you with code compliance.

Is it crazy to add a clean out below fittings I will be adding to test on the stack? I could only find one out of the house and don’t want to test the whole system.

Don't quite follow the question. Isn't a test tee what you add for testing (e.g. with a Cherne Clean Seal), and also what you'd use for a cleanout? So if you need to add a test tee, it would make sense to me to put it somewhere it could be useful for a cleanout in the future, if possible.

Cheers, Wayne

 

[Jeff H Young]

I often use a wye for testing rather than a c/o tee. depending on the test plugs you have.

 

[jim pipe]

I often use a wye for testing rather than a c/o tee. depending on the test plugs you have.

I didn’t get a test ball yet, but like the Cherne as Wayne suggested. Is the advantage of a wye vs c/o tee less turbulence created at stack? I have the room, but would prefer to hide in the wall any way. The inspector didn’t give me guidance, but seemed to suggest the test tee was only for testing and could be sealed if not wanted. I was thinking of positioning so c/o faced inside framing. Any concerns there?