P trap for tub in basement NEW INSTALL

Hello.

Please see my attached pics.

I am putting a tub in my basement bathroom. I am not sure where I connect my tub drain P trap to. I assume I can use a fitting and connect to the vertical pipe just below grade (like I drew in the one of the pics) ? Or does it have to connect to the larger horizontal piping below the slab that connects the toilet to the other piping?

Please advise.

Thanks

need a picture of the plumbing below the floor
my exray vision glasses are not working

you are goint to have to access that plumbing, so pull the plywood and lets look

is that plywood lying on the concrete stab?
That is very unusual.
What is that gray round thing on floor?
is there a hole in slab under that?
could be a p-trap already there.

The floor is covered with a plastic membrane and then plywood to create a subfloor. It can easily be removed if I need more room to dig. I am going to chip up the floor and dig down and see. I am looking at my local plumbing guide and codes and it seems to show a typical 3 piece bathroom with a connection to the vertical 2" just below the cleanout. I am just wondering if that is common practice or whether I the horizontal piece is the correct option.

I will add more pictures when it is chipped up

That grey round thing is a hole through the slab, my basement had a bunch of them. Just gravel under it.

There was an apparant drain under there after all. Am I safe to say that this would be tied in and I am good to connect my tub drain right to this? I would have assumed it would have been routed towards the vertical 2" with the clean-out but that vertical turns the same direction as the drain goes under the slab.

You need to open that up a little and see where those pipes are going. Do you have a backwater valve on the basement piping. That may be why those pipes are running like that. You will want that bathroom group connecting to the backwater valve if there is one.

It’s a new house and it goes right under my furnace. It is safe to assume it was inspected and my home has a back flow. I can’t really open up any more

You would see a access if you had a backwater. I saw that round disc in one of the photos and may have assumed that was a backwater valve. If you tie into a existing 2" line you will need to make sure you are not overloading it. Would be safer tying into larger line. But i am not there so just guessing a little

if that blue on the pipe is a cap...then that s your tub drain.
here is what you need to set the drain
you need 2 walls established

Yes that is a blue cap. I am very happy that the plumber connected a tub drain for me when the house was built. Thanks for the help Frodo. I will just tie my tub P-trap onto that line and I’m set.

it is very important that the edge of the tub, is a minimum 15'' to the center of the toilet
it can be farther, 16, 17 or 18'' it can not be closer than 15''. not 14 3/4
it is a code thing

Hi Frodo,

Yes with the 32" for the tub, I have 15-1/4" to the center of the toilet. You mentioned that I will need a 2" P-trap and reducers to 1-1/2 for the tub? I haven't had the tub out of the box yet but I am wondering why I wouldn't just use 1-1/2" P-trap since the drain pipe in the slab is already 1-1/2".

I brought a garden hose in the house and stuck it into the drain pipe in the slab and opened up another cleanout in the other side of the basement. I turned the hose on and listened in that cleanout for the sound of running water to determine whether that drain was in fact connected to the plumbing. I heard water flowing... good news!

I plan on setting the tub this week.

I hope one of the pro's will correct me if I'm wrong.

I thought everything under the slab had to be 2" minimum.

My local City homeowners plumbing guide states minimum 1-1/2 for showers/tubs. I will call inspector to verify. Since my home is 5 years old I assume this under slab plumbing would have been inspected and passed back then with the intent for a 3 piece bathroom.

I have contacted the inspector for my area. He said that the 1-1/2" shower/bath drain pipe in the slab is fine as long as the trap arm is less than 6 ft. He said since it was inspected it certainly would have been the case and not to worry.