Hi. I am a homeowner and in process of finishing my basement and have hired my own subcontractors. My home was built five years ago (in New Jersey) and has two floors plus the currently unfinished basement space. I have been going nuts trying to figure something out as I trying to figure out how to vent the bathroom plumbing. I realize I will need to talk to my current plumber, but I am a planner and I want to know in advance what I should expect and make sure he does not try to avoid something as I want things done to code, but part of the problem is with how things were done when house was first built and while maybe it was fine for code, it may have made things harder for me now. Fortunately, I have the blueprints from when my home was built and as I try to figure this out, there is something very odd I think with how the original plumber hooked up the various plumbing vents. I'll do my best to explain. When house was built, the builder properly added a 2" future vent line that was supposed to be "capped and tagged" in basement (and I can see where that was "supposed" to be). However, the original plumber seems to have taken the main 3" sewage discharge line (i.e. the one that exits the house to connect to city sewer) and connected a vent line to what should be my 2" "future vent". What really boggles my mind is that I then see a 3" pipe that comes through the basement slab and nothing in basement connected to it. I can go into my attic and see that same 3" pipe come up and then go out to the roof vent. Shouldn't the main 3" sewage line have been connected to that "unused" 3" vent? I just cannot figure out why that 3" pipe comes out of the basement floor slab. I was thinking radon? But there is no fan. There does not appear to be anything mentioned anywhere in my blueprints, including plumbing diagrams that mentions radon. Would it be okay for my current plumber to fix all this by venting the main 3" sewer line and connect to this 3" vent that goes up through to attic and out through the roof so that I can then have him properly tie in the new basement bathroom vent pipes to what was supposed to be the 2" future vent exactly for what it was meant for (i.e. my future basement bathroom)? If so, does that 3" pipe coming through slab matter and are there any special considerations I need to talk to him about and consider.
I added two pics hoping that will help show what I am saying. One is showing the 3" pipe coming out of basement slab, which goes up to attic and out roof. The other shows some connections. On far left, you can see the 3" main sewer line. On top of that just to the right of the red pex pipe, you can see the 2" pipe, which then runs over a few feet to the right and connects to what should have been the future vent. in the same pic on the right side, you can see the 3" pipe that was coming up from basement slab. It does make a 90 bend that looks like it is existing house, but it is actually bending and then bends again to go straight up and through to attic.
I added two pics hoping that will help show what I am saying. One is showing the 3" pipe coming out of basement slab, which goes up to attic and out roof. The other shows some connections. On far left, you can see the 3" main sewer line. On top of that just to the right of the red pex pipe, you can see the 2" pipe, which then runs over a few feet to the right and connects to what should have been the future vent. in the same pic on the right side, you can see the 3" pipe that was coming up from basement slab. It does make a 90 bend that looks like it is existing house, but it is actually bending and then bends again to go straight up and through to attic.