Basement Bath Pipe Routing

[imported_ssabin]

Forgot to ask this in the previous post, but it really is a different question anyways.

Is it possible to run 2" drain lines through 2x4 studs within a non-load bearing wall? A plumbing reference book lists the max hole size in a 2x4 non-bearing wall at 2.5 inches, which is about the size of 2" drain piping (I'm guessing). Assuming that it is OK to elongate that hole in the direction that the stud runs (vertically), I should be able to run this 2" line through the stud wall. However, the same plumbing reference mentions that the minimum distance from the hole to the edge of the stud for a 2x4 stud in a non-bearing wall is 5/8", which would not allow a 2.5" hole.

I would have simply used 2x6 framing for this wet wall, but the plumber installed my rough plumbing drains and sewage pit too close to the basement wall to fit a 2x6 wall. In fact. for the bathroom back wall itself, I'll have to use 2x3 studs. I'm now debating whether I can run the 2" pipe through the 2x4 wall, or whether I should run it outside the wall near the top and enclose it in a soffit.

[imported_ssabin]

Anybody? A general home improvement book that I have suggests that up to 60% of the width of a stud can used for holes in running plumbing lines within non-bearing walls. This implies the max pipe size for a 2x4 stud wall is 2.25" OD, which means 2" drain pipe will not work in the wall.

Anybody have a different opinion?

[Wgoodrich]

The 60% is true allowed for a bored hole in a nonbearing stud wall.

5/8" required from surface edge of stud to bored hole.

YOu need a plumbing wall.

Sounds like you are having a problem with design fit to existing design. If you can take an electronic picture or two then we could see you condition and possibly provide an alternative to provide you with a way to create your 6" plumbing wall.

If you go through the top plate this had better be a vent. Remember that part about drains flowing down hill. Ha Ha.

The rule on the top plate is a notch or bored hole allowed but not over 50% of the width of hte top plate.

If you can email or post a couple of pictures showing what you have to work with we may be able to help you with options.

Good Luck

Wg

[imported_ssabin]

Since I don't have a digital camera, photos will be difficult to implement, but I think I can describe my situation and how I plan on getting around my constraints.

I have a septic system with a roughed-in basement bath requiring a sewage pit and a sewage pump to get the bathroom waste up to the main drain line levels. The lip of the sewage basin is only about 5" from the poured concrete basement wall, so a 2x6 wet wall will not work. I will closet off the sewage basin, which will allow me to run an almost vertical vent line from the basin to the vent stub-out installed by the builder. So, for the sewage basin "closet", the vent line can go up to the vent stub-out by going "around" the top plate instead of through it; there will be no finished ceiling in their.

The problem is that the waste line out of this closet will go up (parallel to the vent line), then will turn left out of this basin closet to hit the main drain line about 10 feet away horizontally. The waste line will essentially run near the floor joists (the basement ceiling supports). It would have been nice to run them within the 2x4 stud wall attached to the concrete basement wall, but the piping is too big (unless I went with 2" thin wall, if there is such a thing, but I wouldn't want to do that with pressurized waste!).

So, I'll just run the waste line in front of this 2x4 stud wall and box in a soffit around it. That is the easiest way to do this, and it will look just fine (well, it would if I could drywall, tape and sand with any proficiency!). The run will be near the top of this wall so the soffit will be quite small in reality.

In fact, I may go ahead and put a soffit around all of the drain line which hangs on the outside walls of the basement, at least that portion in the finsihed living area. That way I can add insulation which will reduce noise. I know, make sure to keep access to cleanouts, which won't be a problem.

You would think the plumber would have left me enough room to put a proper wet wall in place, but that wasn't the case. In fact, in the bathroom itself, there is only about 3.75-4" of clearance between the outside of the sink drain stub and the concrete wall. I don't think I can get a 2x4 wall and 1/2" drywall behind it, but it might be possible if I notch it. I bought 2x3 framing lumber for that wall section (about 6 ft) just in case. I hate to lose the inch of insulation, so maybe I'll investigate notching, especially since that 4" pipe will get converted to a 1.5 or 1.25" sink drain anyways.

[Wgoodrich]

Sounds like you have a plan. Let us know how you come out.

Good Luck

Wg

[imported_ssabin]

The ever-changing plan!