New bathroom

I am wanting to add a second bathroom to my home on the second floor. It was rough plumbed by the home builder many years ago and never finished. It is directly above the main bath and the kitchen. As you can see, there are water lines and the vent pipe for the first floor.

If needed, the dimensions of the room are 10' x 6'. The ceiling height is 88", the roof slope begins 28" from the open wall and drops down to 67".

I am hoping to not have to tear the floor up to do this project. I have a rear drain toilet and raised platform shower in mind, assuming the ceiling will accommodate this.

My questions are: Would there be any issue tying into this vent pipe to use as the drain? Is my plan feasible/realistic?

Any helpful information/advice would be wonderful. Thanks!

 

When you say it was rough plumbed, usually that means that the drains and supplies are there. From the picture, it looks like it's just an empty room.

As for that vent and whether it can be used, it depends on what's below it and connected to it. If it's a main stack, connected directly to the main drain with no fixtures attached it can be used, but more likely, a first-floor or basement bathroom or kitchen probably drains into it. If a lower fixture drains into it, it's a wet-vent and isn't allowed by code.

In that case you'll need to drop a new drain down to your main drain and vent up through the roof or tie into that existing vent.

 

Thank you for your reply. It is the only stack for the house. The 1st floor bath and kitchen are hooked up to it. Installing a new pipe isn't really an option, not looking to tear up the whole house.

 

It may not be a big deal to add a separate drain for a new bath. I had the same issue and I ended up only having to open a wall to run a new drain. My wife wanted a 3rd bathroom and all I could see was hassle. It turned put that it wasn't. I routed the drain between the floor joists to a point where it could drop down through a laundry room wall and into the basement to tie in to the house drain. I think the existing vent is large enough to tie into to vent the new bath.

Just think of the advantages that a 2nd bath provides. When you really, really gotta' go and somebody else is on the pot . . . or no more complaints about the bathroom fan being overwhelmed when you use the bathroom. That might be worth a little extra work.

I do have a comment about the existing vent. It appears to be ABS. In my area that stuff is no longer acceptable and the only way you can tie into it is either mechanically or with a "special" ABS to PVC fitting.

 

It is ABS. Directly beneath this is bath and kitchen, so can't really open a wall beneath it. Code really isn't an issue, only care about function. Live in the middle of nowhere, no ones coming to check it.