Basement Bath DW Runs Question

Hi Guys,
I've been a lurker on here for a few years now. Always was able to find my questions before but now that I'm diving deeper in to a new project I figured I better join now.

I'm putting in a basement bathroom. I'm really moving a toilet and a sink to a new location and adding a shower/steam room. The old area was in the laundry room and my wife is tired of looking at the toilet as she does laundry.
The new area is in a better location, room wise not plumbing.

I have two stacks in the basement so I have a good idea on how the main drain is run. The issue I have right now is a floor drain, I know I can get someone out here to find how its running and its something I'm going to do before I start breaking up the floor, but right now I thought since my luck is bad the drain will be running in my way. So here I am to see if its really not going to be an issue or it might be a big deal.


I drew up some pictures on Sketch-up to show whats going on (I think).

Over the toilet and sink area is a vent line for the garden tub in the upstairs bathroom. I can tie in to the vent to vent the sink and toilet.

Heres my drawings.
The Beige line is the main drain line.


And I think this is how the floor drain runs


Now if I'm right then I hope I can do this.
I'm not 100% sure about the Shower/Steam Room drain.


Now if I have the floor drain running at a different angle


I'm not sure if I can run everything in to the floor drain line or not.

Does anyone see issues any which way I have shown?

A vent must be in the fixture's drain line after the trap. The WC and lav are fine as long as the lav drain is 2" and vented, the WC would not need a separate vent.

The shower will need a vent before it's connection to any other line.

The only way you could connect to the line for the floor drain is if it were 3" and the trap for the floor drain had it's own vent. I would not go there.

edit: typo

The "dimensions" for locations are all immaterial as far as the actual piping is concerned. What is relevent is the pipe sizes and HOW you install the entire system. No matter how you connect the shower room it WILL need a vent for the trap. A "vent line" for the garden tub upstairs would NOT be run in the basement's ceiling, but if it were you CANNOT connect to it, unless it is done 42" ABOVE the floor at the tub.

hj said:

The "dimensions" for locations are all immaterial as far as the actual piping is concerned. What is relevent is the pipe sizes and HOW you install the entire system. No matter how you connect the shower room it WILL need a vent for the trap. A "vent line" for the garden tub upstairs would NOT be run in the basement's ceiling, but if it were you CANNOT connect to it, unless it is done 42" ABOVE the floor at the tub.

Click to expand...

The DIMENSIONS are for distances from main line and to give an IDEA of size of area.
I have sizes on the SINK and TOILET but for some reason it didn't SHOW on the SHOWER and FLOOR DRAIN. OOPS
Actually the vent for the garden tub DOES show up in the basement ceiling. The garden tub drain is a GOOD ways AWAY from the wall so its tied in to the drain and ran up in to the ENCLOSURE for the tub at its highest level and then ran HORIZONTALLY to the wall and then UP THROUGH attic.

Wow TYPING in CAPS every few words is FUN, AND here I THOUGHT it was just to HIGHLIGHT a POINT.
WHAT A DOUCHEBAG

Still, if the vent is below the floor, you will have to intercept it at 42" above on the next floor.
This is to prevent water from going down the vents in case of a plugged plumbing fixture. At 42", the fixture will oveflow first.

42" is used because it's 6" above the flood level of the highest fixture. A kitchen counter is 36" high.

Some places require a trap primer for a floor drain.

It IS to emphasize a point, maybe you missed that. In that case there is no reason to waste it on you. You cannot connect to that vent until it is 42" above the floor of the tub. When it comes to calculating pipes, the dimensions of the room or location of the fixtures do not matter UNTIL you actually install the pipes