Toilets are an incredibly important fixture in any home, which makes it all the more concerning when something goes wrong. I’ve had my fair share of toilet problems over the years, be it a clogged bowl or a leaky base, but thankfully they’ve been easy to resolve with a bit of know how. If you’re currently trying to figure out where your toilet leak is coming from and how to fix it yourself, then you’ve come to the right place.
A toilet leak is usually caused by the wax seal under the toilet failing. If you notice water pooling around the base, it’s a solid indicator that your seal has failed. However, it can also be an issue with another part of the toilet, such as the shutoff valve, supply tube, the tank, or the bowl.
If you want to learn how to fix a leaking toilet yourself, keep reading for an easy step-by-step guide!
Checking if Your Toilet Is Leaking, and Where It Is Coming From
Here are some steps you can take to pinpoint where your toilet is leaking from:
- Remove the lid from top of your toilet tank – This should come off easily, but exercise caution as it can be heavy and you might break it if you drop it.
- Inspect the water level – Inside the tank, there should be a line indicating optimal water levels. This will typically be found on the back or side walls, labeled “water line.” If the water level is below or above the line, you’ll need to adjust the level of water. You can do this with the fill valve found on the left side of the tank, using the guide here.
- Do the food coloring test – Get a bottle of any color of food coloring and put 15 to 20 drops into your toilet tank. Feel free to add more, until the color of the water changes visibly. Wait 30 minutes before checking the toilet bowl for colored water. If you see colored water, that means your leak is between the tank and the bowl. It could be in the overflow tube or the flapper. If you don’t see colored water, you can check other areas.
- Check for cracks on your toilet bowl – You can also use food coloring to check for cracks. Drop it directly into the bowl and observe if it highlights any hairline cracks as it seeps through. You might also notice colored water pooling on the floor.
- Check the base of your toilet – If the leak isn’t due to your tank or bowl, turn your attention to the base of your toilet. If you notice a puddle on the floor, mop it up and observe how and where a new puddle forms. If it’s not coming from anywhere but the base, it’s likely due to loose bolts or a failing wax seal under your toilet.
Tightening Loose Bolts Under Your Toilet
When your toilet is leaking at the base, this is the first fix you should try as it’s simple and easy:
- Locate the tee bolts that secure your toilet to the floor. Some toilets have caps that protect the bolts but you can easily pry them off with a knife or a flat screwdriver, or pull them off with a wrench or pliers.
- Use a wrench or pliers to tighten the bolts on either side of your toilet until it’s firmly mounted to the floor and it doesn’t rock from side to side. Make sure to tighten them bit by bit — don’t over-tighten the bolts or apply too much pressure as you might crack the porcelain and cause a new leak.
If you’d like to see how to do this visually, here’s a great video:
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Doing this can compress the drain outlet and restore the wax seal on your toilet base. If you’re lucky, this will solve your leak problem. If not, you might have to try other fixes:
Removing the Toilet and Replacing the Wax Seal
If tightening the tee bolts didn’t resolve the leak from the base of your toilet, you may need to replace the wax ring that creates a watertight seal between the toilet drain pipe and the sewer line underneath.
This wax ring, also known as a wax gasket, typically doesn’t require maintenance and can last around 30 years. However, a toilet that isn’t properly bolted to the floor or is loose enough that it can rock around can compromise the integrity of the wax seal. Sometimes, the seal can also dry out or fail prematurely.
If this is what’s causing your leak, you have to be prepared to completely uninstall and reinstall your toilet. If you’re not confident in your ability to do this, it’s best to call the services of a professional plumber.
If you’re willing to put in the work, however, here are the steps you need to take:
- Turn off your toilet’s water supply – You can do this using the shut-off valve, typically located behind or under the toilet, and turning it all the way clockwise. In some cases, the shut-off valve itself may also be faulty due to a lack of use. If this happens to you, shut off your water main instead and consult this guide to replace the shut-off valve.
- Drain as much water as possible from the toilet – Remove the lid and flush the toilet entirely, holding down the handle and observing the water inside the tank. When you can’t flush anymore, use a rag or a sponge to absorb all the water in the tank. For the bowl, you can use a plastic cup to scoop up any water left.
- Disconnect the water supply tube – On the shut-off valve, loosen the compression fitting nut.
- Unmount the toilet bowl – This time, you’ll have to loosen the tee bolts instead of tightening them. Pry off the caps and unscrew the bolts. Now that the toilet is loose, grab the rim of the bowl firmly (near the area where the seat hinges are installed). Rock it carefully back and forth to break the wax seal. Once the seal is broken, lift the whole toilet off the floor. Lay it on a piece of cardboard or a blanket, taking care not to crack or scratch the porcelain.
- Scrape off the old wax – You can use a putty knife to scrape off the wax from the toilet and the closet flange (the ring in the floor where the toilet connects to). Inspect the flange and check if it isn’t bent or cracked. If it is, you might need to replace the flange entirely or use a repair strap to fill in missing parts. You can consult this guide for help replacing your flange.
- Install the new wax gasket – You can buy a new wax ring from any home improvement store with a plumbing section. Most wax rings are solid wax, but there are different types of rings you can choose from, such as those made of rubber or foam. Read through this guide for an overview of your options. To install it, you just have to set it down on the closet flange and make sure to center it properly.
- Put the toilet back in place – Once your wax ring is in place, you can carry the toilet once more and set it down onto the wax ring. You can use the tee bolts as guides to ensure that it’s aligned properly. Check the alignment of the toilet tank as well. It should be parallel to the back wall. Once you’ve set down your toilet, press down on the rim as hard as you can to compress the wax gasket and create a watertight seal.
- Tighten the tee bolts – Follow similar steps to the section above. Tighten each bolt slowly, taking care not to crack the porcelain. Replace the bolt caps afterward.
- Reconnect the toilet’s water supply tube to the shut-off valve – Once reconnected, turn the water back on and flush the toilet a few times. If you still notice leaks, you can press down on the bowl again and tighten the bolts a bit more. If the leak has been resolved, you can resume the use of your toilet. After a few weeks, check on the bolts again and ensure that they’re still tightened.
When you notice your toilet leaking from the base, this might be due to loose bolts or a faulty wax ring. Tightening the bolts is a simple fix, but if the leak persists, you may need to uninstall and reinstall your toilet to replace the wax ring. You can do this yourself, but if you’re not confident in your ability to do so, call a professional plumber.