DWV Advice Please...Bathroom + Laundry Room

I am putting in a half bath room in part of my old laundry room. There is a laundry sink and washing machine drain stack existing now. The sink drain is attached to a vertical 1 1/2 inch vent up through the roof. The laundry drain stack is tied into that vent/drain.

I need to move the laundry drain over 90 degrees to the new wall I framed and add a toilet drain. The horizontal drain lines in the basement in this area are 2 inch - so I know I need to change them out to 3 inch.

I would appreciate any advice on setting up the drains and vents the best way. Thanks!

Only hard part I see is how are you going to get a new vent for the toilet up the wall.
The existing vent for the lav is 1-1/2 inch and you need at least 2 inch vent.

Is that a toilet flange on the floor? Was that existing? Maybe it is already tied in//

I just cut the hole for the toilet flange...haven't tied it into the drians yet.

And I thought I was ok with the 1 1/2 vent because the DWV in the basement is only 3 inch.

Thanks.

Vent can be 1/2 the size of pipe you are venting.3" pipe 1 1/2" vent.If you want to go larger vent that is ok.

Under IPC and UPC toilets can be vented with 1 1/2 and the distance from closet to vent is unlimited

Can you advise on the laundry drain. Can I am extend the laundry drain around the 90 degree turn (new wall) and leave it attached to the existing drain stack. Its less than 5 feet away from the vent. Will the the 90 degree turn soon after the trap will cause a problem? Would I have to tie in a new vent after the 90 degree turn (extending up 4 feet, then horizontal over to the existing stack?)

Thanks!

The 90 should be fine. Be sure you are within vent to trap distance though.

Hi Rughead,

That 90 is fine as long as it is a LONG SWEEP 90, but tell us, is wet venting allowed in your area? How are you planning to run the piping for this new toilet...what vents the toilet here and how are you connecting everything? I don't think any code will allow a washing machine to wet vent a toilet, so you probably can't use the 2" (reduces to 1.5") feeding the sink/washing machine as a toilet wet vent, OK? Answer my questions...see what we all think here.

You'll need a 3" cleanout on the new 3" drain at the change of direction where you connect into the existing 3" drain line and another 3" cleanout at the end of the run near the toilet, too, OK?

Back to you...

By the time you finish the job, EVERYTHING you have now will probably be removed and revised. UPC REQUIRES a 2" vent for a toilet. we would have to be there, and it would cost you, to "set up the drains and vents properly". Installing them "properly" is our job and what we get paid to do.