Basement Bathroom Plumbing

ncinqueg · Dec 27, 2013

Hi, Thanks for anyone's help in advance.

I'm kicking around the idea of finishing our basement. First step is outlining the bathroom. Previous owners of our house had the basement roughed in when they built the house. I've had a few people over and have told me that 99% of the time the builders don't put the plumbing in the right spot and they have to be moved. However, I'm trying to save a little $ and trying to make what I have work so I don't have to go through the expense of tearing up the concrete.

With that said, I want to add 1 sink, 1 toilet, and 1 shower.

1) The toilet drain is slightly less than 12" from the vents behind it. After I install a Y in the vent and frame and drywall, I don't think a 12" toilet will work. My local home depot does sell a 10" toilet. Can I make that work? or should I go through the expense of having the drain bumped out a couple inches?

2) The shower needs a dedicated vent correct? I'm assuming (from the picture) I would just tap into that vent, right?

3) Can a sink and a toilet share the same vent? So, I would just splice in a 'double wye" to that vent in the middle, correct?

Any other ideas anyone has would be greatly welcomed!

Thanks!

phishfood · Dec 27, 2013

You should be able to just use a 2" x 1 1/2" sanitary tee on the vertical vent just to the left of the toilet and drain the sink into that, no need for double wyes or anything like that.

A 10" rough toilet will work in that situation, and would probably be easier than moving the drain. I usually elect to move the drain if the tile isn't down yet, but I have the tools and the experience that makes it a relatively simple job, and it saves me the hassle of having to remember to order a special toilet for that bathroom. Don't waste your money on a cheap toilet, buy Kohler or Gerber.

ncinqueg · Dec 27, 2013

Thanks for your help! So, no additional connection (other than water) is needed for the toilet, correct?

phishfood · Dec 27, 2013

By the code I work under, and drawing conclusions and assumptions from your picture, no.

Chadkingsplumbing · Dec 31, 2013

Looking at the pic the pipe that is tying the two vents together is to low. It should be 12" above your highest flood level. That would be your lavatory at about 34" off finished floor, so that pipe should be 46" min.

johnjh2o · Dec 31, 2013

Chadkingsplumbing said:
Looking at the pic the pipe that is tying the two vents together is to low. It should be 12" above your highest flood level. That would be your lavatory at about 34" off finished floor, so that pipe should be 46" min.

If I'm not mistaken that number is 6" above the flood rim.