Help with Plumbing Code for Full Bath

[frontporch]

First post in this forum. I am looking for some guidance trying to wrap up a project that has gone on for years.

I remodeled a 1/2 bath and washing machine that drained into a 3" drain line and had a 2" vent pipe. The house is located in NJ and was built in the 60s.

I did this project after replacing most of the supply and drain lines for my other two second floor baths while adding a second floor laundry. Those passed inspection and overall, for a homeowner, I don't think I made any mistakes. There were no plans for the current project and I did what I thought made sense from what I had learned.

Now I have a toilet, two sinks and a shower draining into a 3" sewer line and I am struggling to run venting through the attic/roof that is 10' from a second floor window. I will follow up with some sketches that hopefully will show more details and appreciate wisdom gained from this site's members.

 

[frontporch]

Some pictures

 

[frontporch]

Some quick sketches coming soon

 

[frontporch]

I am not proud of this sketch. I will try making something reasonable tomorrow morning

The toilet drains through a 3” line with a 2” vent off a 2” wye. This vent stays 2” and goes into attic space
The sinks both drain into separate sanitary tees and continue up the wall with a 2” vent line. The shower is a simple trap that drains into the 3” sewer line that runs between the rafters. If it’s not center by the toilet the. I guess it has no vent. The pictures also show a 4” pvc pipe that is part of the radon system

I am including another picture of the shower drain.

 

[CT18]

If it were me I would have re configured the layout and picked that shower up flat off the drain going to the sinks and wet vented it and the toilet would have been a separate run with a vent. Again I am not a house plumber, wait for Twowhack to give some info

 

[frontporch]

Thanks. I guess it’s never too late to make some changes. If I understand you are suggesting having the shower drain into a trap that crosses under the 3” toilet drain pipe to meet the 2” sink horizontal drain along the wall using a sanitary tee

It’s probably also possible to add another vent pipe in the triangle in the sketch that is all the way to the left. There is already ductwork there so space is tight

 

[CT18]

If you change elevation you break the vent, so jumping up and over would require a vent

 

[MicEd69]

You cannot use a sanitary tee for a drain lying on its back.

 

[MicEd69]

You are correct that your picture shows the shower is not vented. It must be vented before it connects to the main sewer line.

 

[frontporch]

So a sanitary tee going from horizontal run to horizontal run is no good. that makes sense. What about a tee with a long bend (don't know the proper name).

If you change elevation you break the vent, so jumping up and over would require a vent

Not sure I understand this concept. Was that in reference to entering on the vertical part of the 2" line, just before it enters the 3" sewer line from the toilet?

 

[MicEd69]

So a sanitary tee going from horizontal run to horizontal run is no good. that makes sense. What about a tee with a long bend (don't know the proper name).

Yes, it is a Wye and 1/8 Bend Combo or you can use a regular wye and a 45-street ell.

 

[frontporch]

Would this setup meet code? It is a 2” trap that drains to a 2” wye and 1/8 bend combo with n the horizontal run of the sink drain

 

[MicEd69]

That provides a good drain path, but you still need a vent in the trap arm; a vent between the P-trap and the combo fitting.

 

[frontporch]

Crap. The issue is routing a vent pipe. I was hoping in this layout the 2” sink drain would act as a wet vent for the shower

 

[MicEd69]

No, I'm afraid not. If the drain was connected to a single sink drain in the vertical, then that could act as a wet vent, but not in a horizontal run.

Sorry.

 

[CT18]

You need to know what your local code says about wet vent. My area I can vent the shower with a lav/sink.

 

[frontporch]

Really appreciate the insights. I do have another possibility. In the picture below I have the location of a sanitary tee with reducer to 1 1/2”. That could take the horizontal drain from the shower and empty into the vertical part of the 3” line just like the sink does. The vent would have to make a couple abrupt 90s to work it’s way into the attic and join the other vents before leaving the roof

 

[frontporch]

Could use some advice on the last picture. I called my local plumbing inspect about the connection to the 2" horizontal sink drain (previous idea) and he suggested sending in a diagram with the permit application. Permits are a good idea and I have always done, except for this. I will eventually pull a permit, but it may be when I sell the house... The inspector didn't say no to my description of the wet vent on a horizontal 2" horizontal pipe, but he also didn't say its OK either. He did say that the code that is followed is the 2021 national standard plumbing code.

 

[MicEd69]

Sorry frontporch, I was out over the weekend. The above approach is great. You have 2" into a sanitee in the vertical and 2" all the way to the 3" vertical.

The 1 1/2" dry vent just needs to be sloped 1/4" per foot back to the drain line just as if it is a drain. Close 90s will be OK if required, you just don't want to have any pockets. And if things are really tight, the vent can even be 1 1/4" pipe. I've done that in a few places when I've had to squeeze a vent around a 4" riser inside a wall to get to the vent side.

 

[MicEd69]

My area I can vent the shower with a lav/sink.

Can you wet vent a shower into the horizontal portion of a sink drain line? Just curious as I don't think that would meet any code.