Toilet Leaking Into Basement: (Repair It Now!)

Toilet Leaking Into Basement

The toilet is made of different components that perform different functions. These components work together to ensure that the toilet functions properly. A dent or crack in one of these components can leak toilets into the basement.

The two major causes of toilet leaking into the basement are loose tee bolts or damaged wax rings. Other reasons you may have a leaky toilet include:

  • Faulty water supply lines
  • A faulty water shut-off valve
  • The faulty seal between the toilet base and the tank

Toilet leaking into the basement is one of the most common toilet issues that can lead to serious damages if not fixed quickly. If water floods your basement and it isn’t taken care of quickly, mold can begin to grow, which can cause damage to your home and cause potential health problems. In fact, mold can begin to grow in as little as 24 hours if the water isn’t cleaned up properly. Let’s discuss some of the causes of a leaky toilet and how you can fix a leaky toilet.

Why Is My Toilet Leaking Into The Basement When I Flush?

Different reasons can cause toilet leaking through the floor when flushed, but two major reasons that may cause the toilet to leak into the basement when you flush are loosed tee bolts and damaged wax ring. In this article, we will discuss some of the causes of a leaky toilet.

Loosed Tee Bolts

The main function of the tee bolts is to secure your toilet firmly to the ground. These bolts may look insignificant, but they perform a great function. When tee bolts are broken or loose, the seal in the toilet base can break, and this can cause leaks. You will need an adjustable, box-end, or open-end wrench to fix this issue.

Damaged Wax Ring

A damaged wax ring is another reason why your toilet may be leaking into the basement when you flush. You can test this by flushing your toilet and seeing if water leaks around the base. If water leaks around the base, then it means that the wax ring is bad. You will need to replace the wax ring with a new one to fix this issue.

When changing the wax ring, the first thing you need to do is remove the toilet. The wax ring is inexpensive, and you can easily change it by yourself with your toilet repair kits. Wax rings are available in different models and sizes, so you need to be careful when buying a new wax ring. You may need to describe the damaged wax ring and your toilet model to the hardware store attendants to get the best wax ring replacement.

Faulty Water Shut-Off Valve

Another reason your toilet may be leaking through the floor when flushed is a faulty shut-off valve. To check if your water shut-off valve is faulty or not, you may try to tighten the valve gently. If the valve falls into your hand during this process, it means that the water shut-off valve is bad, and you need to change it. Also, if you tighten it and the problem persists, you will need to buy a new valve a new tube.

Faulty Water Supply Lines

Faulty water supply lines also cause toilets to leak into the basement. If the water supply line is not well connected to the valve or tank, water may be leaking into the basement. To prevent leaks, you need to ensure that the rubber seal is still intact and the nut is tight. Finally, a broken supply can also cause toilet leaking into the basement.

How To Take My Toilet Apart?

Once you have detected why your toilet is leaking into the basement, the next thing you need to do is fix it immediately. If you don’t fix it immediately, it may lead to a greater problem that will cost you more money to fix. To repair the leaking toilet into the basement, you may need to take your toilet apart. It may not look easy if you have not tried it before, but you should be able to do it with the help of a step-by-step guide.

The following steps below will guide you on how to take your toilet apart without stress successfully:

  • The first thing you need to do before disassembling your toilet is turn off your water supply and flush the toilet. Use a bowl to get the remaining water in the tank.
  • After emptying the toilet tank, the next thing you will do is unscrew and remove the water supply tube from the shut-off valve.
  • The toilet bowl is held down by two bolts known as tee bolts. You will have to remove these two screws before removing the toilet seat. You will need a plier and an adjustable wrench to unscrew the bolts. If the bolts are corroded, you will need to cut them with your hacksaw.
  • After removing bolts, you will lift the toilet and place it apart. To prevent sewer gas from entering your home, you will have to block the drainpipe with a rag.
  • After removing the toilet, you will need to clean the debris and the caulk on the floor. You may need to use a putty knife to scrap the existing wax seal.

How To Repair Leaking Toilet Into The Basement

After setting your toilet apart, the next thing you need to do is carefully check each component to which of them is faulty. Are you still unsure whether you can repair a leaky toilet or not? The steps below will guide you on how to repair the leaking toilet into the basement:

Inspect The Flange Carefully

Seal failure is one of the things that cause toilet leaking through the floor when flushed, and the common reason why the seal fails is the Flange. If the Flange is faulty, you may need to install a reinforcement ring.

Installing the Reinforcement Ring

Before you install the reinforcement ring:

  1. Make sure you clean the Flange.
  2. Apply caulk around the top of the ring, then place the ring on the Flange.
  3. Ensure that the reinforcement ring is properly placed in the right position before tightening the bolt.

Reinstall The Toilet

Make sure the caulk is set before you start reinstalling the toilet. Tighten the toilet bolt after placing it in the right position.

Frequently Asked Questions (FAQs)

  • How much does it cost to repair a leaky toilet?

It is not a fixed price because different reasons cause a leaky toilet, but the average price for toilet repair is $70-$220.

  • What are the common causes of toilet leaks?

The three common causes are faulty flapper, damaged wax ring, and faulty water supply line.

  • Will a low flange affect the seal?

Yes, a low flange can affect the seal. If it is low, you may need to install an extender ring.

  • What will happen if I don’t fix the leaky toilet quickly?

It may lead to serious damage.


Toilet leaking into the basement issue is a common toilet issue that you can easily fix if you have the essential tools. The first thing you need to do is to disassemble the toilet.

After you have successfully disassembled the toilet, fixing the problem is next. But before you start fixing the problem, you must know the main reason why your toilet is leaking into the basement. When you know the main problem, it will be very easy to fix it permanently.

Keep reading to learn how to repair the leaking toilet into the basement.

Leave a Comment

Your email address will not be published. Required fields are marked *