Toilet Leaking Into Basement-Causes and How to Fix

Toilet leaking in your house is a major problem that requires instant fixation before causing damages to the home. Leaking water from the toilet moistens your basement, making the place weak leading to other damages such as property damages.

There are several causes of toilet leakages. For instance, loose water supply lines result in water leaking to the basement instead of flushing the water. Therefore, it is advisable to frequently inspect your toilet to identify any problems and fix them earlier enough before damages worsen.

Causes of toilet leakages and how to troubleshoot the problemsToilet Leaking Into Basement

There are several reasons why toilets may leak. The reasons include;

1. Failure of the wax ring to seal correctly

Sometimes, the toilet wax ring may fail to seal the toilet because it has worn out or is no longer sticky, and once the wax ring seal wears down, water leaks to the basement. To fix such issues, replace the wax ring seal and see if the problem is solved.

2. Loose water supply pipesLoose water supply pipes

Once the water supply line has become loose, the direction of the water supply changes, and instead of water flushing out, it leaks to the basement causing damages. First, inspect your water supply pipes and try to tighten them using a rubber seal. If the problem persists, check other possible causes of toilet leakages.

3. Loose bolts

The bolts are located at the base of your toilet, and once they have become loose, the toilet loosens, resulting in water leaking to the basement. Troubleshooting the problem requires tightening of the bolts. Also, you can consider replacing the bolts.

4. Toilet cracks where water leaks to the basement

Toilet cracks may be deep enough to allow water to seep into the basement through the spaces. First, inspect your toilet and see how deep the damage is. Try sealing the cracks on your own but, if the cracks are deep, contact a plumber to help you fix the problem.

5. Damaged or blocked draining pipes

This problem is the leading cause of toilet leakage blocked or damaged pipes. Once your toilet draining pipes are clogged, water being flushed flows back to the basement. Once your draining pipes are clogged, consult a plumber to unblock the pipes. Also, try fixing or replacing the damaged drain pipes.

Steps on how to fix toilet leaking into the basement

Steps on how to fix toilet leaking into the basement

       i. Collect all materials required to fix the leaking toilet

Materials required to fix a leaking toilet include; new wax ring seal, screwdriver, nuts, bolts, cleaning rugs, gumboots, drill, rubber gloves, rubber seal, etc.

     ii. Inspect your toilet carefully and identify any damaged parts

Check your toilet for any possible causes of toilet leakages. Check every part and record all damaged toilet parts. Finally, inspect your toilet for any condensation. If there is any condensation, try using a new tray, use an insulated water tank, and troubleshoot your toilet flapper.

Identify all causes of water leakages and try fixing them one by one. Ensure you use the recommended steps of solving each problem.

  iii. Disconnect the toilet from its position

Remove the toilet from its position and check the wax ring seal after switching off the water supply to the toilet. Secondly, remove all water from the toilet and the toilet tank. Ensure the toilet is empty before proceeding to the next steps.

Remove the tee bolts and nuts from the base using a screwdriver and a wrench. Keep the bolts safe for use after fixing the problem. Lift the toilet away from the floor and place it in a different clean place. Ensure you lift carefully to avoid damaging or cracking your toilet.

Check if the toilet is cracked. If the toilet is broken, try using a rubber seal to hold it in position. If it is damaged beyond repair, consider replacing the whole toilet.

  iv. Check the wax ring seal

Inspect the wax ring seal and identify if it requires any replacement. If the toilet wax ring seal is no longer pliable and intact, consider replacing the wax ring seal. Using a putty knife, remove the old wax from the draining open. Install the new wax ring seal and screw tee bolts firmly.

 v. Inspect the tee bolts

Check if the tee bolts of the toilet are loose. If they are loose, try tightening them using a screwdriver or a drill. Ensure you tighten the bolts at the base of the floor to prevent any leakages. If your bolts are corroded and rust, consider replacing the tee bolts to improve water flow efficiency after flushing.

  vi. Check the draining pipes

Inspect your draining pipes if they are in a good state. If the lines are damaged, consider replacing them with new ones since it is hard to replace a broken pipe. But, if the tubes have been blocked, try unblocking them using the required materials. Unblocking is allowed out of the toilet after flushing the water.

vii. Clean your toilet using a toilet brush

Before reinstalling the toilet, clean the toilet using warm soapy water and a hard toilet brush. Wash the toilet and try removing all stubborn stains. Rinse the toilet thoroughly with clean cold water and leave the toilet to dry completely. Ensure you wash each part correctly.

viii. Reinstall the toilet to its position

Once the toilet is dry, lift it slowly and return it to its initial position. Align the toilet with the holes at the base of the toilet. Also, ensure the toilet comes in contact with the replaced wax ring seal. Screw the tee bolts into the holes using a screwdriver. Ensure you tighten the bolts to prevent any leakages.

Further, tighten the nuts slowly to avoid breaking the porcelain. It is advisable to be careful when lifting the toilet to protect it from falling.

  ix. Reconnect all pipes to the toilet

After reinstalling the toilet successfully, connect all pipes to the toilet, such as the draining pipes and the water supply pipes, correctly. Ensure you tighten them appropriately to prevent further leakages.

  x. Test your toilet

Try flushing water and check for any leakages. If there are still leakages, try repeating the fixation process with a lot of carefulness. But, if the problem persists, consult an experienced plumber to help you fix your toilet leakages.

Moreover, you can consider replacing your toilet, especially if it has stayed for a very long time.

Considerations when using the toilet to prevent leakages

To prolong the lifespan of your toilet and to increase its efficiency and effectiveness, consider the following:

  1. Check your toilet regularly at least every three months to ensure your toilet functions as required.
  2. Use recommended substances to unblock your toilet. Strong chemicals may damage your toilet pipes and other parts.
  3. Avoid flushing other substances.  Substances such as pads may block the draining pipes resulting in water and waste leakages to the basement.
  4. Once you identify any toilet issue, ensure you fix the problem instantly to prevent more damages to the toilet and toilet parts.
  5. Clean your toilet regularly.


Toilet leakages can pose a danger to your floor and any property around. If your toilet leaks, the information above will help you know how to determine the causes of toilet leaks. For instance, you can check the toilet wax ring seal, water supply pipes, water draining pipes, etc.

Moreover, you can be able to solve the issue on your own before contacting a plumber. The steps described above are easy and straightforward to follow by everyone. Finally, ensure you follow the manufacturer’s instructions on how to care for and manage your toilet.

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