I noticed water leaking out from under a toilet, so I decided to take a look, hoping that it was something simple (wax ring or even a hairline bowl fracture). The toilet came out with (almost) no problem -- the nut on right-hand closet bolt got tricky when the bolt started spinning on me. Once I got the toilet off, I found out why the bolt was spinning: the flange was mounted (IMHO) incorrectly -- with the closet bolt slots closer to 11 & 5 o'clock than 9 & 3 o'clock. I also noticed that the slots at 9 & 3 were cracked, probably from being tightened down during the previous installation.

This picture got rotated; as-is, this would have been the left side of the toilet as you approached it (the tank attached to the supply line you see).

old toilet flange

This is where I probably should have stopped and used a "covering"-type repair flange on top of the existing one, now that I know about them, but it bothered me that this one was put in incorrectly, so I started to take it out.

I have access to the under-side, where I see what looks (to me) like an extender that's mounted on top of the elbow. Neither the flange nor the extender rotate by hand, so while I'm suspicious of the previous work, it does seem like they glued these together.

I've made a bit of a mess, so I'm asking for smart/experienced approaches to completing the removal and replacement of this flange.

Here's the current top view:

old flange, front view

And closer from the top: you can see the damage I've done in trying to get it out so far -- this one also got rotated counter-clockwise when I uploaded it so the sink drain and tank supply line are at 6 o'clock from here:

old flange, closer up

and here's the view from the bottom:

old flange and down-pipe, from below

enter image description here

I'm in the USA; this is my first under-the-floor plumbing adventure.

I found this similar post on DIY with a comment from Ed. I don't have a sawzall/oscillating saw to make a good horizontal cut, nor any way to make a good chamfered cut, so my suspicion is that it's time to call in a professional, but wanted to see if there were any other options before throwing in the towel, since it's already being put to use!

  • Wow... Take another picture in the basement looking down the line from the flange so we can see the line better. All the connections should be glued and not spin. The type of flange you had doesn't spin as well. Feb 5, 2019 at 2:53
  • No. Down the line. So the picture you have, take a picture to the left so we can see down the line. Feb 5, 2019 at 2:56
  • Uploaded a picture showing more to the left in the basement Feb 5, 2019 at 2:58
  • How did you make those cuts into the pipe? Feb 5, 2019 at 3:05
  • The vertical cuts are from a hand saw and a jigsaw. Feb 5, 2019 at 3:06

4 Answers 4


There are bits available that will drill out the interior part of a glued in joint. The pipe that goes into the 3X3X2" wye pipe could be drilled out using this.

enter image description here

Then glue back in what you need to get the flange in place.

  • If I had seen this attachment at the hardware store, I would have gone for this idea, since my vertical hacking was getting nowhere fast. In the end, I called in a plumber to finish the job. I wasn't there when he did the work, but from the second-hand description, this sounds like what he did. Self-answer forthcoming with pictures. Feb 10, 2019 at 1:06

A simple hack saw or even a hand saw for wood can cut that pipe then use a utility knife to chamfer the inside. Plastic pipe is not that hard you can cut and assemble without glue to make sure everything fits once happy glue them together.

  • I started this the wrong way -- from above; if I'm understanding you correctly, you'd saw it off from below and build back up? Where would be the ideal place to make the cut? Feb 5, 2019 at 16:04
  • You have 1 hub there so that one is easy just unscrew go to the right several inches for the other cut and to remove the flange at the slight split between fittings will allow everything to be removed, then a section of pipe a 90 a y and a flange will be needed, take this photo with you to the plumbing or big box store you can use a coupling or a hub to the right and don't forget glue. Once you get the pieces home pre assemble everything once you are happy start gluing and your plumbing task will be done in short order and you will have saved a bunch of $.
    – Ed Beal
    Feb 5, 2019 at 19:47
  • This is the direction I would have gone if I had more time, ambition, and confidence in my skills. Lacking experience but having kids in the house, I went with plan "C" and called in a local plumber to finish the job (self-answer forthcoming). Feb 10, 2019 at 1:05

I know this is an old post, but now might be a good time to visit the flange display shelves of your local hardware store. There are pieces to replace sections of flange lips, flanges that fit over and into old flanges, metal flange lips, flanges that fit the outside of plastic pipe, cast iron flanges, etc. There are actually specialty hole saws to remove flanges and some diy videos on making same...there are also specialty pipe cutters as depicted above. I would avoid busting out the flange as you did...in the future. The diameter of the pipe (3"? 4"?) is good to mention for future posters with similar questions.

Had to replace one recently that had no concrete below it for anchoring purposes.


In the end, my lack of experience along with the inconvenience of being "down" a toilet with kids in the house led to a call to a local plumber. I wasn't home during the repair, so I can't say exactly what was done, but I "lucked" out in that the toilet continued to leak even after their repair. I again suspected a crack somewhere in the bowl, so I purchased a new toilet and replaced it. I can't find a crack in the bowl, so perhaps one of the tank bolts had a leak that found its way to the bowl area -- I'm not sure.

After removing the old toilet, here's a shot of the plumber's repair (from above):

repaired flange area

... and job finally complete! Only took one more trip to the hardware store for a hacksaw to shorten the closet bolts for the caps.

replaced toilet

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