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How to Repair a Leaking Toilet (Quick & Easy Steps)

repairing leaky toilet plumber

We’ve listed all of the most common reasons the toilet might leak and the steps you need to take to fix each one. Join us while we discuss flanges, floats, flaps inlet hoses, and more to help keep your toilet leak-free.

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Repairing a Leaky Toilet Tank

To make it easy to follow, we’ve decided to list the reasons your toilet might leak from simple to complex. Hopefully, you won’t need to read long before you find your problem.

Determine the Cause of the Leak

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Photo Credit: cunaplus, Shutterstock

The first thing you want to do is find the cause of the leak.

  • If the outside of the tank is wet and there is a small amount of water on the floor, but you do not hear the toilet running, it’s probably just sweating.
  • If the toilet continuously runs for a few seconds every few minutes and shuts off again. It’s probably worn flapper at the bottom of the tank.
  • If the toilet continues to run after the tank is full and you can hear water pouring down the overflow, you have a worn shut-off switch.
  • If there is water by the valve that comes up from the floor to bring water to the toilet water, the shut-off valve or inlet hose can be faulty.
  • If you notice a puddle of water at the toilet base, water stains on the ceiling, and occasional foul odors, you probably need a new wax ring on the toilet flange.
  • If there’s water dripping from the tank, it’s probably cracked.


Leakage of water from a toilet_cunaplus_shutterstock 2
Photo Credit: cunaplus, Shutterstock

Sweating is a common problem during the summer months. As the air warms up, it holds more moisture, and the cold water in your toilet makes the perfect surface for the water to condense. On humid days you can collect quite a bit of water around the toilet, especially if you use it often.

  • A small amount of water collecting on the tank is not harmful and completely normal during the summer months, but if you noticed damage occurring, there are some steps you can take.
  • You can use a condensation tray to collect water as it drips from the tank. You will need enough room around the toilet to get the tray in place, and you will need to empty and clean it regularly, but a condensation tray is a very easy solution to a swearing toilet.
  • Make sure family members limit hot shower times to reduce humidity in the air.
  • Keep the door and window open.
  • Turn on any fans, and place a portable fan in a room to increase air circulation.
  • If you have more than one bathroom, restrict access to the sweating toilet during the hottest part of the day.
  • You can install an anti-condensation toilet tank liner to help insulate the tank and prevent it from becoming cold. Unfortunately, these insulators don’t work very well and are best suited for minor condensation issues.
  • You can also install an ant-sweat valve. This special valve mixes warm water with the cold water when your tank refills. Many experts say the anti-sweat valve is the best way to prevent condensation, but you need to have a hot water line nearby, and you will need to use the hot water tank every time you use the toilet.

Worn Flap

Old water pipes toilet_Pradit Jaemfa_shutterstock
Photo Credit: Pradit Jaemfa, Shutterstock

When you have a war and flat water will slowly leak out the bottom of the tank. As the water level falls, the float will sink, which will trigger the mechanism to refill the tank. As the condition of the flap worsens, the tank will fill more often.

  • Changing the flap is not hard and usually only requires fastening two plastic or metal clips. You will also need to connect a chain to the flushing lever and adjust it until pressing the laver raises the flap enough to flush the toilet. Adjust it by changing which chain link the metal clip is attached.

Most modern flaps look like the one we’ve linked to, but there are still plenty of antique models in operation that may require more effort to change and find a replacement.

Sticking or Improperly Set Floater Switch

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Image Credit: VGstockstudio, Shutterstock

If the floater is not stopping the switch when the tank is full or not starting the water refill when the tank is flushed, you will need a new toilet fill valve. The fill valve is the heart of the toilet and is responsible for the water level in the tank and starting and stopping the water flow. Many people choose to change the flap when they change the toilet’s fill valve, and many kits include both components. If your positive that flap is in good shape, you don’t need a pink change and save the step.

  • To change the fill valve, you’ll need to empty the tank by turning off the water that feeds it on the floor next to the toilet and flushing.
  • Unscrew the water hose that connects to the faulty valve from the shut-off valve.
  • Loosen the plastic nut that holds the fill tube in place at the tank’s outside base and remove the faulty component.
  • Insert the new component by reversing the steps with the new fill tube. First, place the valve in the toilet, tighten it with the plastic bolt, and then attach the water line from the shut-off valve.
  • If you don’t get a good seal where the fill valve meets the toilet, it can leak out the bottom.
  • You adjust the water level and tank by twisting the still bells before installing it, and there may be other adjustments to make as well.
  • Some water-saving fill valves may have additional chains to connect a flush lever.

Shut-off Valve and Inlet Hose

Close-up of a professional toilet reparation_Photographee.eu_shutterstock
Image Credit:, Shutterstock

Usually, a pipe comes up from the floor and immediately stops at a valve that you can use to shut off the water leading to the toilet. This valve is the shut-off valve, and the hose leading from it to your toilet is the inlet hose. It’s much more common to see a leaky inlet hose because it tends to crimp overtime from changing refill valves, which causes the hose to wear quickly in that area resulting in leaks. It’s less common to see a leaky shut-off valve, but the internal threads wear out over time, and they can become hard to turn.

  • To replace the inlet hose, you need to shut off the water at the shut-off valve. Empty the toilet, remove the plastic bolt from the inlet valve, and use the proper sized wrench to unscrew the hose from the shut-off valve. Install the new hose is by reversing the steps.
  • To replace the shut-off valve, you’ll need to shut off the main water supply and remove the inlet hose. Next, you use a large wrench to grip and twist off the faulty valve and replace it with the new one. Replace the inlet hose, and you’re good to go.

Toilet Flange

If you have water coming from under or inside the toilet, it is most likely a problem with the toilet flange, which will require replacing the wax ring that seals the toilet to the floor. This project is a little more involved and not something everyone is willing or able to take on.

  • To replace the wax ring, you will need to unbolt your toilet from the floor so you can remove it and have access to the wax ring underneath. You’ll need to scrape away the old wax ring and replace it with a new one before reinstalling the toilet.

It’s a relatively easy but messy job. You won’t need any special tools, and the toilet’s weight does most of the work of seating the wax ring correctly to create a tight seal. However, you will likely need to deal with some waste material, and some toilets can get quite heavy. Unless you tackle this problem immediately, you will have a damaged floor that will require much more extensive and costly repairs.

  • Pro Tip: Never pour hot water in the toilet as it can melt the wax ring.

Cracked Body

If water is pouring from the tank, you most likely have a cracked body. Unfortunately, there’s no way to fix a cracked tank, and you’ll need to replace the entire toilet. You might be able to use a silicone sealant to repair it temporarily, but you won’t want to let it go because that much water can cause a lot of damage. Unless you recently purchased your toilet, you might be pleasantly surprised to find that a new toilet can save water and reduce monthly water bills. Many modern toilets also have a stronger flush and easier to service parts.

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The most common issue with the bathroom toilet is a leaky flap that allows water to run down the drain causing the toilet to keep refilling. The next most common problem is a faulty refill valve that fails to shut off the water once the tank is full, so the toilet continues to run. Both problems occur frequently, and you can expect to change these parts more than a dozen times in your life. The other problems are fairly rare, but they do occur. You should always prepare for the worst and keep extra parts on hand, so you can tend to any leaks before the problem worsens.

We hope you have enjoyed reading have found some helpful tips to keep your bathroom dry and operating properly. If we have helped answer your questions, please share this guide to repairing a leaking toilet on Facebook and Twitter.

Featured Image Credit: docent, Shutterstock


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