New Utility Sink going into main basement stack

[phinsil6]

Hello,

I am looking to install a utility sink in my basement very close to the main sewer stack. In the below picture I am looking to install the sink basically exactly where the 5 gal bucket / dust cyclone is mounted to the wall. Maybe a little to the right but obviously want some working room between the sink and the hot water tank. My main question is, what is the best way to tie into the main sewer stack this seen going into the basement floor? I had thought about installing a threaded sanitary tee where the cleanout currently is and having a new cleanout on the top of that new sanitary tee but now am thinking this may not be allowed based on some research elsewhere. I have a sneaking suspicion that I will need to cut off the current wye fitting and place a new one on but am not sure of what will be needed to replace it with for accommodating the new utility sink. Which is why I am looking for guidance on this forum from all you wonderful people.

Also as a sidebar question. There is an 1 1/2" random PVC pipe going into my basement floor and it doesnt tie into the main stack BUT does go upstairs somewhere and I have no idea what this is. Would you all have any ideas or ways to figure this out?

Thank you!

 

[Jeff Handy]

The random pipe might be a passive radon vent, venting air from the gravel which sits under the basement slab, it would go out the roof without joining the plumbing vents.

Looks like a stupid location for it, they are usually nearer a wall or in a location not right in the way like that.

What the heck is that pvc pipe running along the floor?

Never mind, I see now it is dust collection.

 

[Rickyman]

I’m not sure you should install a sink that close to your electrical panel

 

[phinsil6]

Jeff Handy - I don't think it's radon, i have an active radon 3" going into the floor 14' away. This 1 1/2" runs over to the center of the floor and then upstairs somewhere. I'd love to be able to make it go away somehow; only i have no idea what it is lol.

Rickyman - I appreciate the concern but that will be handled some other way. It's a subpanel that is fed with a GFCI breaker. If that still wouldn't fly with an inspector then I'll just install a wall in between. My question is more about how to make the main stack cut-in.

 

[Jeff Handy]

Check your house blueprints about the mystery pipe.
The city or county might have a copy, if you don’t.

 

[SHEPLMBR]

That line going to nowhere is your best bet. It is probably a future rough in for a sink.

 

[phinsil6]

Jeff Handy - I don't have any blueprints, have never considered the city or county...will have to try that, but i doubt it because it just a standard builder home in a subdivision and i understand the builder was going under around the time it was built.

Sheplmbr - I can't use the smaller pipe. there is no way to run a drain that doesn't box in my HVAC and hot water tank and that seems a bad thing to do

 

[Jeff Handy]

Run every fixture in the house, one at a time, while someone has a hand on that mystery pipe.
If no water comes down it, then it is not a drain.
Ask any neighbors with the same weird pipe if they know what it is.
If no one else knows, or has that pipe, you can probably eliminate it.
Leave that floor space open for awhile, in case something pops up that shows it needs to be recreated.
Such as a drain upstairs suddenly backing up.
Meanwhile, you can put a plug in the floor, and cap off the high end.
While you have the bottom end open, see if there is a trap down there, or does it just go into a drain line, or is it dead ending there at the gravel.
I still can’t see why they stuck that pipe out there all by itself, in the flow of foot traffic.
PS why is there that one foot difference in slab height to next room?

 

[phinsil6]

Run every fixture in the house, one at a time, while someone has a hand on that mystery pipe.
If no water comes down it, then it is not a drain.
Ask any neighbors with the same weird pipe if they know what it is.
If no one else knows, or has that pipe, you can probably eliminate it.
Leave that floor space open for awhile, in case something pops up that shows it needs to be recreated.
Such as a drain upstairs suddenly backing up.
Meanwhile, you can put a plug in the floor, and cap off the high end.
While you have the bottom end open, see if there is a trap down there, or does it just go into a drain line, or is it dead ending there at the gravel.
I still can’t see why they stuck that pipe out there all by itself, in the flow of foot traffic.
PS why is there that one foot difference in slab height to next room?

Those are all clever ways to determine the use of the pipe thank you. on the other side of that ~1 block high wall is open gravel and a "crawl space". I have since built a wooden decked workshop over that 16x16 open pit.

As for the cut-in for the main stack, do I just cut the existing wye off at the bottom and then install a double wye with one end going to the existing drain, the other going to 1 1/2" reducer to main sink and the vertical section of the wye going to the cleanout?

 

[Jeff Handy]

Pros need to advise on that, it is beyond my skill level.

 

[SHEPLMBR]

Pros need to advise on that, it is beyond my skill level.

I've said what I thought. I am 99% positive on it. Unless it is a sump line.

 

[Hamberg]

Love to see the resolution on this one! Not sure how that slab-pipe was allowed in front of the service box to begin with - or was that panel added after? And where exactly is the main drain in the pic? Also, is the PVC off to the side of the WH part of the dust collection?

 

[phinsil6]

Sheplmbr - I can't install into that small 1 1/2" line. As I've said it either isnt a drain line (haven't been able to confirm yet but i KNOW its not sump or radon). I also can't because the utility sink drain line would box in the mechanicals.

Hamberg - The main drain is the 3" coming out of the ground in front of the electrical panel. I just put in the subpanel in early 2020 (it's my workshop feed). and yes the 2" PVC directly adjacent to panel is dust collection. and I too would love to see the resolution of how I can cut-in to the 3" main stack sewer line

 

[Hamberg]

I just put in the subpanel in early 2020 (it's my workshop feed).

Think I was over-thinking this... Why wouldn't you just use a wye? Pull a AAV off if you need it.

 

[Twowaxhack]

I’d use a San. Tee in place of that cleanout. Relocate the cleanout to the top of my new San tee. And replace the plug with an AAV IF there’s no other way to vent to atmosphere. I do not like to use AAV’s, personal preference.