Basement Bathroom Rough-In Help - Plumbing Forum

charlie902 · 01-23-2012, 05:57 PM

Hi guys

I'm in the project of finishing my basement and the builder of the house did all the rough-in for a bathroom in a basement. I'm having a hard time trying to figure out what is what and how to frame the walls around it.

Here is a picture of my current rough-in.

I'm assuming the big pipe on the bottom of the pciture is for the toilet, where should the sink and shower go? do I need to vent them out all the way to the roof? How should I frame this? I initially put some tape on the floor where I was thinking to put the walls, but then I realized I need to make sure I have space for the toilet and vents.

Thanks in advance for your help

**phishfood** · 01-24-2012, 12:07 AM

The 4" in the foreground is for the toilet drain. The 2" closest to it will vent the toilet.

The 2" with the 6" sleeve around it is most likely for a shower, though it looks a little close to the concrete wall for a center drain shower, maybe for a bathtub, but bathtubs are usually brought up 1 1/2"? The 2" pipe behind it up against the concrete wall is likely the vent for the shower/tub.

The biggest question is which of the two different 2" vent risers is intended to serve as the drain for the lavatory. Without an onsite inspection, it might be hard to tell.

And since this is a basement, you aren't anywhere close to me.

**johnjh2o** · 01-24-2012, 01:33 AM

I would think that either vent could be used as a lav drain.

John

**Another-Plumber** · 01-24-2012, 02:17 AM

good news is the pipes look good

charlie902 · 01-24-2012, 01:26 PM

Thanks for the replies.

What are the recommendations for the layout? I'm looking for the position for the toilet, sink and standing shower.
As far as I know, the toilet needs to be separated a couple of inches from the walls. Can any one confirm those numbers? and also suggest positioning of everything

Thanks!

**johnjh2o** · 01-24-2012, 02:14 PM

The toilet needs to be 12" to center of the pipe from the back wall and a minimum 15" from the side wall.

John

**phishfood** · 01-25-2012, 12:25 AM

My concern is if one of the two vents is designed as a flat wet vent, instead of a stack vent. If that were to be the case, then that vent needs to have the lavatory washing down it.

**johnjh2o** · 01-25-2012, 01:03 AM

I see your point but being the slab is already poured all we can do is guess with out using a camera. Unless there is an as built available.

John

charlie902 · 01-25-2012, 02:09 AM

Whats the difference between a flat wet vent and a stack of vent? What can i do from here to try get more info from your guys?

**phishfood** · 01-26-2012, 12:40 AM

A stack vent is accomplished by turning vertical with the drain pipe, using a tee to attach the fisture (in this case either the shower drain or the toilet drain) to the vertical drain pipe, and then the pipe above that tee is a stack vent. Since the pipe is vertical, it is highly unlikely for anything to become lodged in that pipe.

A flat wet vent would be if you were to attach the fixture to the horizontal (flat) pipe, and then turn vertical with the vent. If something is piped this way, the flat section of the vent pipe needs to have a small fixture draining through it, to wash away any debris so that the vent will not become clogged. It is common practice to install a flat wet vent, and use the lavatory drain to wash it.

So, if you were to cut the caps off of the two possible vent pipes. If you can use a light to look down into the pipe, and you can see that there is a tee on the vertical pipe, you can just vent that pipe out without attaching the lavatory drain to it. If all you see is the fitting turning back horizontal, then it needs to have the lavatory drained through it.