I am noticing some water spots on my concrete in my (unfinished) basement. When I look up for the cause of the water I can see water dripping around the hole that is used for the sewer pipe for the toilet (upstairs). (Note: there is a lot of duct work around that spot, but I am fairly sure that is the source.)

Close examination around the base of the toilet (and in the upstairs bathroom in general) shows no water or moisture of any kind. It also only seems to leak when I flush it (I tried not flushing it for a few days and the wet spots started to dry out.)

So, I am not sure what to do. Should I rip my toilet off and try and fix it? Any ideas on how to do that? (I have never needed to install a toilet before.)

I am reasonably "handy" around the house, but if this is going to be a big/complicated job I would like to know so I can just hire a plumber.

2 Answers 2


You can try replacing the wax ring. Usually, that will fix the type of leak you describe.

Essentially, there is a wax gasket which seals the area between the flange (in the floor) and the porcelain (on the bowl). Due to age/movement/etc, this gasket will eventually fail, and cause leaking when the toilet is flushed.

Replacing the ring is a relatively straight forward procedure:

  • Remove the toilet
    • Turn off the water to the bowl
    • Disconnect the flexible water pipe from the shutoff valve
    • Flush the toilet, holding down the handle to get rid of as much water as possible (use a plunger to push the remainder out)
    • Loosen the bolts on either side of the bowl (These may be corroded or completely stuck. You may have to hacksaw these off)
    • Gently rock the bowl side to side to release the seal, and then move the toilet off of the drain
    • Invert the bowl, exposing the seal on the bottom of the toilet.

  • Install a new wax ring
    • Remove the old wax material from both the bowl and the flange with a putty knife (you will likely also find a plastic "funnel", which can be removed as well)
    • Take your new wax ring, and install it on the bottom of the bowl (the rounded portion will be facing up towards the bowl.
    • If you were forced to hacksaw the bolts from the flange, install the replacement bolts to the same position on the flange.

  • Reinstall the toilet
    • Lift the toilet back up, and thread the bolts through the holes on the side of the bowl (do not let the wax ring touch the ground until you are ready to drop it in its final position).
    • When the bowl is in its final resting position, sit on the bowl to seat it in place. Rock back and forth gently to squeeze the wax ring. The base of the toilet should now be resting on the ground around the entire base.
    • Reinstall the washer and bolts holding down the toilet. Be careful when tightening these bolts (do a little at a time, switching between the 2 as you go). You do not want to break the flange or the bowl.
    • Trim up the bolts with a hacksaw to adjust the length (if necessary). Reinstall the plastic caps over the bolts.
    • Reconnect the flexible water line to the shutoff valve
    • Turn on the water
  • 1
    great detailed answer. Commented Jan 8, 2011 at 12:49
  • 1
    Don't forget to clean and inspect the closet flange. Sometimes the flange will corrode and split where the bolts insert. If the flange is damaged, there are simple repair kits to assure your bolts hold the toilet down snugly. Commented Jan 8, 2011 at 13:37
  • 2
    Solid Answer! Followed your steps and that fixed the leak. Thanks so much!
    – Vaccano
    Commented Jan 9, 2011 at 0:56
  • 2
    When cutting the bolts on the side of the toilet a hacksaw is sometimes awkward, you can Wrap some duct tape around one end of a hacksaw blade (to create a handle) then use just the blade to cut the bolts.
    – Tester101
    Commented Jan 10, 2011 at 17:40
  • Thank you for this - we're going to tile our bathroom floor soon, and I was very nervous about having to remove the toilet. Commented Jun 6, 2011 at 10:55

There are three common reasons for water near a toilet.

  • Condensation on the tank, coming from a too cold water supply.
  • Wax ring problems.
  • Cracked base.

The first case seems ruled out. If the outside of your tank was wet, then it would have been the answer. The solution there is a water tempering valve. I've done this twice, and had splendid success in both cases.

Replacing the wax ring is a good idea. If so, then James has given you good instructions. But, when you pull the toilet, you need to check to see if there is a crack, as this is also a common reason for your problem.

Regardless, when you do pull the toilet, you will want to replace the wax ring.

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.