Our main supply line enters through the basement floor. I need to move it about 2-3 inches out of the way because it's blocking a corner of the bathroom I'm framing in.

Supply line is PEX with galvanized elbow enter image description here enter image description here

Context of where this is in the bathroom enter image description here

Am I safe to chisel out or use the angle grinder to remove enough concrete so I can reposition the supply line? The concrete around it is not the same type as the rest of the floor.

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    Would be safer to notch the wood. You are kind of working blind with removing the cement and possible chance of tool slipping and cutting/nicking water pipe. What type of pipe is coming from floor? Plastic can have some give to it, but not too much. – crip659 May 6 at 20:08
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    Would still notch the wood, it is faster and easier than fooling with cement. You are not supporting weight of house so notches(even big) are okay. Even moving the wood a bit, will be easier. – crip659 May 6 at 20:35
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    Wood is much nicer to move/notch/ build around stuff, than trying to move plumbing or cement. It can be done, but why make more work for yourself. You basically just want the wood to hold drywall. – crip659 May 6 at 20:43
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    For that section in the corner, can you position the bottom plate over the supply and brace it? Or cut a groove out of a 4x4 to be used as bottom plate? – P2000 May 6 at 20:46
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    I would make sure to leave it visible from the other room (not the bathroom) that looks like an unfinished space. If that's the vanity chalked out on the floor in that corner, I would leave a very generous opening behind it. Murphy's Law dictates that as soon as you cover it up completely is when it will start to leak. Hidden pipes also have an uncanny ability to attract drywall nails and screws. – spuck May 6 at 22:06

Either make the bathroom 2" smaller or 2" bigger.

If you are committed to moving the line then use a hammer drill to put a hole where you want and reroute the water main from the outside in (this will require you to dig outside, cut the line, and install a new line). If you go this route then I recommend installing PEX as that will be easier to work with (well, easier for me anyway).

I would not recommend trying to make the current hole bigger and push the current line out of the way. This puts it under tension and increases the risk of it breaking. Galvanized pipe gets brittle with age, so it loses what little flexibility it ever had and you run the risk of cutting the line while expanding the hole.


I just took another look at your photo. Don't know why I thought that was a galvanized pipe. Looks like PEX to me. I still recommend against expanding the hole and putting the pipe under tension.

###EDIT 2###

The updated photos and detail helps. Thanks for the updates. I didn't realize this was coming through the floor. Here's my recommendation. These are not load bearing walls, so I would either keep the framing and plumbing as is, but not take the corner framing all the way to the floor (as others have suggested). Just notch out the bottom. Or, get rid of that elbow and run the PEX straight from the floor to the ceiling (I assume it goes there anyway, but it's your call).

Personally, I think your best bet is to do as little as possible with the plumbing and work around it by notching your bottom board. This will allow future access when things break.

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    The elbow looks galvanized, pipe does look plastic like. – crip659 May 6 at 20:24
  • the supply is PEX with a galvanized elbow – EMAW2008 May 6 at 20:25
  • OP can't make it 2" bigger because of the floor drain outside, and can't make it 2" smaller because it's already too cramped. Looks like 4 inches on either side of the murder-scene toilet between the sink and the long rectangular object. – jay613 May 7 at 12:58
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    @jay613 Ya, I realize that. The original post did not have those details. Instead of rewriting my answer I just added edits at the end. Not an ideal situation, for sure, but I still think notching is the best option. – tnknepp May 7 at 13:02

Let's assume you can't make major changes to the bathroom layout because the drains are already installed in the concrete floor. Right?

So ... taking the suggestions to "notch it out" just a little further: Where you have your chalk sink, install a wall-mounted sink without a cabinet beneath it. Frame out the bathroom with a large cubic indentation cut out of the bottom corner, and open to the outside. Large enough that a plumber needing to work on that pipe can get in there with both hands and tools, large enough you could even get a hammer drill in there if necessary. You don't need that space, underneath the sink and in the corner, to be inside the bathroom. The sink can overhang the framed-out cube slightly. The cutout shouldn't be so large that it interferes with the sink drain.

You could possibly customize a vanity cabinet there by cutting out the rear left corner to accommodate my suggested extra framing. Just make sure that what remains of the cabinet is strong enough to support the sink, perhaps by adding fasteners to the left wall.

  • Yes, the drains are already in. notching around it seems to be the way to go. WE had considered a pedestal sink. That would allow for access to the supply as you've described. – EMAW2008 May 7 at 13:34
  • I'd do this too. With this approach there's no need for a bottom plate exactly there. You can have a (covered) access cubby from the "out"side or you can provide access from the inside by a removable cabinet under a wall mounted sink/vanity or floating counter. Install a mini-header at the height of the sink/cabinet for mounting and stud support. Access would be required, what, once maybe in the next 20 years? – P2000 May 7 at 18:05

If you do want to move that pipe, you can chip and patch concrete to do so if you wish. I've chipped out over a hundred plastic and metal pipes, frequently for the same purpose. You have to use good technique to avoid puncturing the pipe and having to chip it back further, but it's more about patience and methodology than anything. Depending on what surrounding concrete I'm trying to remove, I typically use a combination of careful perforation with a hammer drill, electric chipping and hand chipping. Looking at yours and the angle the pipe comes up at, assuming I've interpreted your diagrams correctly I could do it in about an hour and a half in high MPA concrete with a 3 lb mini sledge hammer (long hammers like carpenters hammer make it harder to aim and control), 3/8 chisel and 7/8 chisel. Chip it back far enough that you can bend the pipe enough without kinking it.

Use a chisel with a guard and wear gloves of course. When you're chipping, bear in mind, you're not trying to break it all at once. You're trying to concentrate force with the chisel so that a small piece (or chip) can't take the force and breaks off. Usually getting started is hardest, and usually I'll start by hitting with a corner of the chisel to dig the point in, then tilting 30 to 45 degrees and continuing to strike so the force is applied "under" a chip. If you're chipping out a pipe, you almost never chip towards the pipe. Instead you chip on angles beside it so if your bit or chisel slips it won't puncture the pipe.

I also find with hand chipping it can help to vary the rhythm you use, like usually I'll start with two moderate hits to set the tip and then one hard hit to free the chip, and if the chip doesn't fly, I'll move the point and try to free the same chip from a different nearby angle. Hitting in one place over and over generally will eventually set the chisel in or sometimes break concrete, but it's faster, better and usually more clean/accurate to use multiple angles to weaken the chip, especially if you don't have a hammer drill on hand to perforate the concrete (carefully of course without perforating the pipe).

  • Do you think the pipe will then move 2in? That's another part of the problem I believe. – P2000 May 8 at 2:17
  • @p2000 yeppers! Looks like PEX similar rubber or plastic. In any case it's just a matter of removing enough concrete. This pipe in particular looks to come up at an angle in a favorable direction. I've most often done this with PVC or metallic electrical pipe which often must be chipped back to the back of the 90 to cut and couple. Based on the red line stud outline and steep pipe angle, this one looks easy. With a hammer drill, chipper and chisels, I can carefully remove a cubic foot of concrete in 2 to 4 hours, less with my big chipp – K H May 8 at 2:28
  • Less with my big chipper and only 1 pipe to worry about. Sorry on mobile. I've more than a few times done this repair on large intersecting pipe banks, which becomes more delicate, but if There's only one pipe to worry about it's pretty easy. – K H May 8 at 2:30
  • Based on what I see this case needs 1 or 2 litres of concrete removed, so 2/27 of a cubic foot. Sorry I'm Canadian so I think in metric and imperial for different things. – K H May 8 at 2:34
  • It does highlight the value of good in slab layout and mounting methods. Some tradesmen see 50% extra time in layout and mounting jigs as a waste, but often one chipping job eats 10x that amount of time. I've met electricians who don't think it's worth duct taping all in slab core line couplings, but if you lose one pipe the cost is usually enough to pay for all of the cases of duct tape for that project. The general also doesn't always warn you before they drop a special product like agilia in a slab, which will fill a pipe through a pinhole. – K H May 8 at 2:41

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