I need to do a temporary fix for a sinking toilet. I'm trying to find the right tool to remove a small area of tile, adhesive, and thinset. The layers of flooring are:

  • old floor
  • 1/4" plywood
  • cement board (at least I think it is -- I can't really see it)
  • thinset
  • tile adhesive
  • 9" square 1/4" ceramic tile

This only needs to last for about 6 months, so my plan is to:

  1. take out the toilet
  2. remove the 4 tiles around the waste pipe
  3. chisel out the cement, thinset, and adhesive
  4. cover the area with an 18" square piece of plywood
  5. replace the toilet

My question is: what would you use to chisel out the cement, thinset, and adhesive? I'd rent a demolition hammer, but I'm pretty sure that will wreck more than just 4 tiles worth. I've considered a hammer drill, a rotary hammer, or a chisel and a drilling hammer (i.e. manual), but I'm not sure if those are strong enough.

And, of course, the other (implicit) question is always: is this even a good idea?

Thank you!

  • 1
    What is the story about why the fix only needs to last six months? Are you planning a full bathroom remodel at that time? Or are you anticipating a "quick fix" and then move away in six months? If this latter it does not seem like a very lofty goal.
    – Michael Karas
    Dec 1, 2016 at 15:32
  • Excellent use of username in comment. Yes, we are doing a full remodel in 6 months. I just don't want anyone ending up in the downstairs apartment's bathroom before then. :)
    – LoftyGoals
    Dec 2, 2016 at 19:25

1 Answer 1


For a small job like this I would use a hammer and a hand chisel like this Make sure to use safety glasses it is wild how far some of the chips can fly. I would inspect the Joist's on both sides of the toilet if the area has rot these may need to be repaired and part of the cause for the sinking. If you would like a new hammer drill most 1/2" models will work quite well in this application without the heavy impact of a hammer and chisel (home models).

  • Thank you! I've been looking around at hammer drills (considering the Dewalt DWD520 corded 1/2"), but there's something I'm not sure I understand -- it seems to rotate even in "hammering" mode. If that's the case, what kind of bit would you use? I can't see how a chisel would work...
    – LoftyGoals
    Dec 3, 2016 at 9:50
  • Starting at the edge of the tile it is easy to chip then get the flat under the edge with the chicle at ~30 degrees a smack with the hammer will usually pop the tile. With the backer board usually a light hit will score it enough that it will break on that line, I have many corded and cordless drills my favorite is my 1/2" DCD985 with 4 mp hour batteries (the 5 AH battery's are ok but the case is easily broken) the 3 & 4 AH have sustained up to 6-8' falls without damage the 5's break 2'.
    – Ed Beal
    Dec 3, 2016 at 16:51
  • Ah, sorry -- I should have been more clear. I meant that I can't figure out how to use a chisel bit with a DCD985 or DWD520 because they rotate. Popping the tile I get, and using a hammer and chisel to crack the thinset I get, but I can't figure out how to use a non-SDS hammer drill to get through the thinset. All the videos I've seen use an SDS rotary hammer. I'd be open to picking up a rotary hammer (ala D25323K) if that's actually the better tool -- I anticipate having to do a few jobs like this.
    – LoftyGoals
    Dec 3, 2016 at 17:39
  • I do have a Hilti that you can turn the rotation off and it is like a mini electric jack hammer but it takes special bits that are a bit expensive but they last. I. Will look up that model and see if it is similar.
    – Ed Beal
    Dec 4, 2016 at 5:55
  • In your original answer you suggested I could use a 1/2" hammer drill... how were you suggesting I use it?
    – LoftyGoals
    Dec 4, 2016 at 8:33

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.