Our house is on a concrete slab. We are planning on installing a second-floor full bathroom, and hoping to connect the new bathroom 3'' PVC waste pipe to the below-grade drainage system at this point:

enter image description here

I think that this (oakum/lead filled) fitting connects the visible 2 inch pipe to a 3 inch, cast iron pipe buried below the concrete: on the one hand there is '3-2' molded on the exterior, and on the other hand, a few feet downstream, there is a WC that must feed into that very same submerged cast iron pipe.

But I could not find this fitting/hub on the web to be absolutely sure.

Does a) anyone recognize the fitting to identify it? Well enough to provide a specific reference? [I have no guess as to the meaning of the XH molded in high relief on the fitting.] And b) do you agree that it is fitted to a submerged 3 inch pipe?

Assuming some positive answers to the preceding, my follow-up question is: will I have to remove the hub/fitting to connect the new 3'' PVC? Namely, does this fitting constitute the equivalent of a 3 inch diameter 'long radius 90 degree elbow' or (better) a 45 degree elbow? I am assuming that the fitting will have to go, and I will have to break up enough of the concrete to join to the hoped-for, 3-inch cast iron pipe.

To be clear: we are replacing/removing the 2'' DWV pipe in the image above.

FWIW - I am drawing up plans to submit to the town, and would like them to correspond somewhat to reality.

Thanks in advance!

  • Edit: As Ecnerwal points out in the comments, the 'XH' surely means 'extra heavy.'
  • 1
    XH is evidently "Extra Heavy" in cast iron pipe nomenclature. charlottepipe.com/Products/Assets/02A-Cast_Iron_List_Price/…
    – Ecnerwal
    Feb 12, 2021 at 18:13
  • "does this fitting constitute the equivalent of a 3 inch diameter 'long radius 90 degree elbow' or (better) a 45 degree elbow?"- assuredly not, because it has a 2" inlet... What goes down the 2" pipe right now? Feb 13, 2021 at 0:03
  • @JimmyFix-it the 2'' pipe is a wet vent, connecting to a sink (lav), and then (somehow - I have not opened up the ceiling through which it must run) to the vent stack. With my 'does this fitting .." I had been wondering whether I could simply cut off the 2'' portion.
    – peter a g
    Feb 13, 2021 at 1:51

1 Answer 1


Pull this out.

enter image description here

Charlotte Pipe 3-in x 2-in dia Reducer Cast Iron Fitting, Lowes

And put this in.

enter image description here

Fernco 3 in. Hub x Cast Iron Service Schedule 40 Weight Donut, ferguson.com

If it doesn't connect to a 90 degree elbow hooked to a wye laying on its side, it was done wrong in the first place. That's the only situation you should have to bust up concrete.

  • Thank you very much. No matter what, this is of course very helpful. That said, I am not sure I understand your "If it doesn't connect to an 90 elbow hooked to a wye lying on its side". As I understand the code, I need to have something like a long radius 90 degree elbow with one end pointing upwards to receive vertical flow. Is that what you mean I should hope/expect to see? Secondly - "pull this out." Will there be anything other than brute force required to do this?
    – peter a g
    Feb 13, 2021 at 2:05
  • @peterag - Likely there's a short stub coming up out of the elbow. I'm not sure if you'd be able to tell if it was a long sweep or not, I'd just assume it is (wink). Secondly, wiggle it. Oakum joints don't like that.
    – Mazura
    Feb 13, 2021 at 2:13
  • Thanks again. I don't know that I will 'assume' if I can tell it's not a long sweep, as in that case I probably won't be able to sleep (slave to stupid conscience).
    – peter a g
    Feb 13, 2021 at 2:21
  • Namely, if the code said I had to sing "God Save The Queen" for the plumbing to be up to code, I would probably feel obliged to do so.
    – peter a g
    Feb 13, 2021 at 2:23

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