Change from S trap to P trap

[John Prekup]

Hi everyone,

I have a question in regards to a double vanity in my upstairs 2nd floor bathroom. The house is about 30 years old and I'm currently updating the batroom. It's has a tub shower, toilet, and a double bowl vanity. It currently has S-traps for both of the sinks.

Since I have the bathroom stripped down to the studs and have access to below the floor I was wondering if there would be way to install p-traps and correctly vent these fixtures.
Their are a few problems though....
The wall that is behind where the vanity sits is a 2x4 wall and has a header directly below it. I could pack the wall out 2" and change my toilet from a 12" to a 10" which would gain some space but I can't go any further than that since my toilet flange is right up against the floor joist( that 3"sanitary tee is missing in the picture - It was broken and needs to be replaced).

Top pic shows 2" drain from tub on left into a 3" sanitary tee then 90 to basement

Bottom pic shows two 1 1/2" drains from sink to below floor. Left one goes through floor then 90s into 3" sanitary tee. Right one goes the through floor then to right and loops back to 3" vent.
Vent is 3" that goes to attic through roof.

Any help/ideas on what could be done to make this work would be greatly appreciated.

Thanks,
John

 

[John Prekup]

Some pics from below

 

[Sponsor]

 

[Terry]

If your cabinet has a kick space under it, you can use that space like this. Where is the vent that you have now?
Also, those santees on the horizontal should have been wye or combo fittings.

 

[John Prekup]

Thanks for the reply Terry.

I have not ordered the double vanity as of yet so I could defiantly get one that has the space under it so that would work.

The vent is a 3" that is in the adjacent wall in the 2nd picture. (To the right)

So if I just 90 that 3" vent under the floor and pickup the 2" sink drain with a single 3"x3"x2" wye that would work?
As far as the vent. Could I run that exactly like your pic and 90 around to the 3" stack vent? Shown in my 2nd pic above?

John

 

[Terry]

A 3x2 wye to pick up the lavs, and then in the attic if that's easier for the vent to the 3" vent to the right. Or drill it over at 42" above the floor.

 

[John Prekup]

Ok that sounds good. Heres what it would kind of look like then.

Tub is not under as this drawing shows but parallel to the 3" (like if you were looking down from the top.

John

 

[Terry]

The tub should come in upsteam of the toilet, not downstream as the drawing shows.
The toilet drops into a wye or combo, not a santee. The tub comes into a wye or combo.
Long or medium sweep on the tub.
You getting closer.

 

[John Prekup]

Terry,

Would this work under floor?

Top of pic would dump to 90 to basement
Toilet off 1st 3" wye
3 x 2" Combo to tub
Right side 2nd 3" wye with 2" reducer to sinks
Left of bottom wye continues to 3" vent through attic roof.

 

[Terry]

I like that better.
The toilet when flushed is guided downhill with that.

 

[John Prekup]

Thanks for all your help Terry

I'll post some pics when it's roughed in

 

[John Prekup]

Ok here is the final rough in. Nothing is glued as of yet in case I need to make changes.

1 1/2 out of top of double sanatee ties into 3" vent in attic

Any concerns?

John

 

[Asktom]

You have used a double sanitary tee to split off to the two lavs, it should be a double fixture tee.

 

[John Prekup]

Didn't know their was a difference but I see it now. I get one and change that.

Anything else look out of place?