Gap between the floor and the commode

Ronald Crafton
by Ronald Crafton

A gap has appeared under my toilet in my master bathroom after 20 some years the toilet is still tight and I don't know why the Gap has appeared can you answer this for me


  11 answers
  • It could be an issue with movement in the flooring or even possible subsidence in your home.

    • See 1 previous
    • 17335038 17335038 on Dec 17, 2020

      Is the floor in front of the commode still level? I am wondering if perhaps the flooring in the WC/bathroom has shifted down on one side of the room which has resulted in a gap?

  • Mogie Mogie on Dec 17, 2020

    This is the only thing I could think of perhaps this could be a flange that has moved over time.

    A toilet flange is supposed to set on top of the finished floor (no gap or space). Then the flange must be screwed through the finished flooring and into the sub floor. You can get away with a flange being slightly recessed below the floor by using a thicker wax ring or the wax free seal you mention.

    You might be OK with the flange raised above the floor if, and only if, the plumbing was cast iron. PVC or ABS pipes would allow the flange to move, and that means the seal would be compromised.

  • Redcatcec Redcatcec on Dec 17, 2020

    Sounds like you need a new flange to be installed. So far, it does not seem to be a settling problem. If you suspected a settling problem, you would probably see it happening elsewhere near the toilet.

  • If the toilet is still tight, it may be the floor. Check the subfloor for rot. It may need to be replaced.

  • Kathy Gunter Law Kathy Gunter Law on Dec 17, 2020

    Here are a few things that I have seen that might cause this:

    You could have a crack in the base which has caused a tiny amount of water to seep into the sub flooring and it has began to separate.

    A small event (similar to an earthquake or storm) could have caused your mobile home to slightly shift and settle.

    Dampness from underneath has caused the sub flooring to degrade over time.


    The only way to know for sure is to get a good look from the crawl space underneath or take it apart and investigate from the bathroom floor side.

  • Recreated Designs Recreated Designs on Dec 17, 2020

    Hi, unfortunately, it could just be that your house shifted slightly. The earth is always moving and settling so even a very slight movement or sinkage of the house could cause this. It has happened at our cottage a few times and things end up being off-kilter or wonky. We have just had to live with the little gaps now :)


  • Johnavallance82 Johnavallance82 on Dec 17, 2020

    Hello Ronald,

    If you have timber floors, it could have dried out a bit and shrunk back. You can fix this using a Silicone Sealant! If it is concrete could still be shrinkage, but of a different kind. If you seal the gap and it returns, maybe you should have someone look at the problem for you.

  • Vimarhonor Vimarhonor on Dec 17, 2020

    Hello. It might be best to get a visual inspection of the situation to detect with the problem is by removing the toilet. Then you can check the flange and the wax seal as well as inspect the floor below to see if there any issues that need to be addressed and corrected.

  • William William on Dec 17, 2020

    I agree that the floor has dropped or sagged some. Check the subfloor from underneath if you can.

  • Libbie B Libbie B on Dec 21, 2020

    Hopefully it's just the wax seal. My husband replaced ours last week and it was pretty easy.

  • Cynthia H Cynthia H on Mar 24, 2021

    Hi! All too often the old wax seal gives out. Check under the subfloor if possible as the floor may be getting wet from a hidden leak. That could be causing problems you can't see. Good luck!