Ask Me Help Desk - Venting a new shower

Venting a new shower

I am installing a shower in a basement bath. The bathroom was roughed in for a tub with a 1 1/2" drain, but when the concrete slab was poured, they filled the tub drain box with concrete so I am left with a solid block of concrete where that drain was to be.

I am installing a fiberglass shower stall 24" to the left of that unusable tub rough in, using 2" PVC. The toilet is locate 48" from this new shower drain, and the toilet is vented through a 2" dry vent.

I intend to tie the shower drain into this toilet vent line. I will use a wye fitting and slope the drain at 1" over the 48".

Is it a problem venting this way?

Thanks

Hi Rghoch...

Sounds like you have this one nailed! If you pipe this as you suggest, you will be WET VENTING The shower. Here, the toilet vent will act as a vent for the shower as long as the toilet vent remains 2" until it connects into another 2" vent above... ;)

The wye fitting is crucial as is the 1/4" pitch per foot.

Let me know if you have more questions...

MARK

Thanks,

The 2" vent line from the toilet is 2" all the way until it tie into another 2" vent line.

Why do you say the wye fitting is critical? I intended to use a 2" Sanitary tee to tie into the vent line.

Quote:

Originally Posted by massplumber2008

Hi Rghoch...

Sounds like you have this one nailed!! If you pipe this as you suggest, you will be WET VENTING The shower. Here, the toilet vent will act as a vent for the shower as long as the toilet vent remains 2" until it connects into another 2" vent above...;)

The wye fitting is crucial as is the 1/4" pitch per foot.

Let me know if you have more questions...

MARK

Quote:

I intended to use a 2" Sanitary tee to tie into the vent line.

Will this san tee be located above or below the slab? Cheers, Tom

The tee will be below the slab in an 8" void above a sand base. (The slab was poured over a void box which, over the years has deteriorated and left a void beneath the slab.) I have cut through the slab and have access to the vent line where it rises out of the fitting below and behind the toilet. Is there a difference between using a sanitary tee and a straight tee?

Thanks

QUOTE=speedball1;1659108]Will this san tee be located above or below the slab? Cheers, Tom[/QUOTE]

RG Hoch...

You can't use a sanitary tee fitting to connect a drain line on the horizontal... against all plumbing codes. You must use a wye fitting and 45s to get to the new shower drain if you are connecting on the horizontal.

You can use a sanitary tee fitting on the vertical, however, but that would require the drain line to be buried pretty deep.

Let us know more...

MARK

P.S.: In waste and vent work there is no straight tee fitting... we call them sanitary tee fittings.

Quote:

Originally Posted by massplumber2008

RG Hoch...

You can't use a sanitary tee fitting to connect a drain line on the horizontal...against all plumbing codes. You must use a wye fitting and 45s to get to the new shower drain if you are connecting on the horizontal.

You can use a sanitary tee fitting on the vertical, however, but that would require the drain line to be buried pretty deep.

Let us know more...

MARK

P.S.: In waste and vent work there is no straight tee fitting...we call them sanitary tee fittings.

Thanks for the guidance. I can use a 45 and a wye, no problem.

Bob

Quote:

Originally Posted by RG Hoch

Thanks for the guidance. I can use a 45 and a wye, no problem.

Bob

Just to close out the entire subject, I dug more of the sand out beneath the slab and, lo and behold, the original 1 1/2' tub drain dropped down into a 2" drain reducer, then the 2" PVC connected into the waste stack.. I cut the old 1 1/2" tub drain out and tied the shower drain into the 2" drain.
I didn't have to mess with the vent at all, and it works great.

Thanks for all your help, fellows.

Bob