How deal with leak in drain pipe from upstairs toilet?

E.C. P
by E.C. P

Water leaks outside of drain pipe onto basement crawl space when toilet is flushed in second floor bathroom. Problem persists after replacing toilet seal.


  12 answers
  • I would call a professional. A leak like that is going to do severe damage.

  • Redcatcec Redcatcec on Mar 08, 2021

    I agree with Adrienne, call in a professional who can fix this, it maybe more involved than what is presenting. They can figure out exactly what and where it is leaking and make the effective repair.

  • Zard Pocleeb Zard Pocleeb on Mar 08, 2021

    Sounds like the leak might be in the drain pipe or the supply line. You’ll need access so you can see the drain and supply lines when the toilet is flushed. Then, have someone flush the toilet while you observe the plumbing. The leak should be fairly obvious.

  • Kathy Gunter Law Kathy Gunter Law on Mar 08, 2021

    You may have a crack in the fixture. We had an issue like that and couldn't figure out the origination of the leak until we remove the it and then we could see it. $100 for a replacement toilet with everything (seal, seat, bolts,) from Lowe's.

  • Cheryl A Cheryl A on Mar 08, 2021

    it could be a seal or a number of things here is info for you it may be time to replace the toilet if it is really old



    https://www.youtube.com/watch?v=urmU3xJSyew

  • FrugalFamilyTimes.com FrugalFamilyTimes.com on Mar 08, 2021

    This sound like it could be potentially toxic - this is a safety issue too - a professional should look at this and advise you.

  • William William on Mar 08, 2021

    If there is no water on the floor in the bathroom then it more likely is not the toilet seal. You might need a plumber especially if the drain pipe is cast iron. Probably a crack or separation in the joints. if it's PVC and your handy it can be repaired if you can locate the leak. Cut out the damaged part and replace with new pipe.

  • Mogie Mogie on Mar 08, 2021

    Call a pro and have this taken care of asap before more damage is done.

  • Lifestyles Homes Lifestyles Homes on Mar 08, 2021

    An extra thick/big wax ring is cheap, in case you a want to give it a try.

  • Deb K Deb K on Mar 08, 2021

    Hi there, it may not be the seal that is the problem, chances are that the toilet itself has a crack, enough to leak, but slow enough you don't see the water leaking, and also because it it going under the flooring when it does. This can lead to the floor rotting out. I would buy a new toilet and wax ring and clean any damage up before installing the new one.

    https://www.youtube.com/watch?v=Y_hVZ3rPzm4

  • Em Em on Mar 09, 2021

    Most common reason for toilet leak is wax ring. If that is not the case then it could be a crack in the porcelain.

  • Annie Annie on Mar 09, 2021

    The seal is more then likely not doing its job. Replace the seal again. Get the seal with the flange insert that goes in the pipe a bout a inch...