I'm remodeling a bathroom, and I have this wall tube from the old sink drain:

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I need to extend this wall tube a foot or so further out from the wall, due to the position of the new sink, and I'm wondering what's the best way to proceed. I think the wall tube is 1.25 inches in diameter and it's very shiny so I'm guessing it's chrome, but I'm a novice so I'm not sure. It appears to be soldered to the drain stub coming out of the wall; this stub pipe also seems to be 1.25 inches, except for the wider part at the end, and looks like it might also be chrome. Here's a close-up of the fitting:

enter image description here

Should I try to unsolder this fitting so I can completely replace the old wall tube with a longer pipe? Or would it be better to cut the old wall tube off before the elbow with a hacksaw and use some kind of compression or slip joint to attach an extension pipe to it (which would run to the P trap of the new sink).

Here's a photo of what's inside the wall -- I actually have access to see on the back side of this wall. It's in a location where I was able to reach my phone in to take this photo, but there isn't enough space here to use a wrench or any other tools to do work on this side, without demolishing part of the wall to create more space.

enter image description here

I'd appreciate any suggestions; thanks!

  • if you pull back the escutcheon and look into the wall does it transition from chrome to galvanized? you might just be able to unthread this pipe from the pipe it joins in the wall and thread a new one in its place. Nov 27, 2021 at 18:10
  • I think it does transition from chrome to galvanized; I edited my original post to add a 3rd photo showing what's inside the wall. I don't have experience with this but my gut is to be hesitant to try unthreading this for fear that I might not be able to get it out but might damage the chrome pipe in the process. Does that seem reasonable, or do you think I should go for it? FYI the joint in this photo is in a tight space where I can't get to with tools (but I was able to stick my phone in to take the photo).
    – embeepea
    Nov 28, 2021 at 2:44
  • I would guess the last picture is dusty chrome-plated brass tubing, not galvanized pipe, so the transition is from chrome-plated brass to cast iron directly at the fitting in the last picture. But a picture looking in with the escutcheon pulled back would be helpful.
    – Ecnerwal
    Nov 28, 2021 at 2:57
  • Hopefully you are keeping the tube plugged while it's disconnected, except for the picture? You want to prevent sewer gas from coming into the room that way. That's an elderly and "unusual these days" setup, without even getting into the details of whether it does or does not actually transition to galvanized pipe before hitting the cast iron - that soldered joint is more typically a slip-fit sliding joint with a nut and a gasket these days. I'm not sure what the best way of updating that is.
    – Ecnerwal
    Nov 28, 2021 at 3:05

1 Answer 1


The quickest thing is likely to cut the pipe square with an angle grinder or recip saw, debur the pipe and use a furnco to convert from chrome to 1 1/4 abs.

It does look like the chrome goes to cast iron.

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