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Why Is My Toilet Leaking at the Base? 6 Common Causes


Why Is My Toilet Leaking at the Base

Why is my toilet leaking at the base? Good question and one not to be ignored! That water you can see on the floor is contaminated by your toilet and if left it may cause an unpleasant smell and damage.

Please hear the plumbing sirens and be determined to do something about it. Your first option could be to call the plumber. If that is not convenient then you need to read this article so you will know what to do.

In this article, you will learn about 6 of the common causes of a leaking toilet base and how to handle them like a pro!

1. Check for Condensation

If you suspect the base of your toilet is leaking you will need to eliminate some possible causes of this water. One of those potential causes is condensation from the toilet itself.

Basically, as cold water enters the water tank of your toilet it changes the surface temperature on the outside of the tank. If the weather is warmer or air is warmer in your house then it can begin to condense on the outer surface of the water tank.

This collection of water can then run down your toilet and onto lower surfaces. If this is happening then you can at least feel relieved you do not have a toilet leak.

2. Leaking Water Shut-Off Valve

This is the small tap that allows the water supply to connect to your toilet. Like any tap or valve, it can be prone to leaking over time with wear and tear.

The way to test this is to get a small bowl or cup and hold it under the shut-off valve and then turn off the water supply after flushing the toilet. If the tap is working then you will hear the water supply has been cut off and your toilet will stop re-filling.

If the valve is maintaining a proper seal there should be no leakage at all. If the join or connection has become slightly loose or the seal is damaged then you will start to see evidence of trickling water. Tightening this up or replacing the seal should do the trick.

3. A Leak From the Pipes

Where there are pipes there can be leaks. One of the first things you will need to do is get an old cloth and thoroughly dry down your toilet and any nearby surface areas.

Once you have a dry environment you will be in a better position to see where the leaking water comes from. Once the area is dry, flush the toilet and wait for any signs of leakage.

As a general point, if the leak occurs when you flush then the problem is likely one of those below. If the leak occurs without needing to flush then it may be related to the pipes. You can use your hand to feel along the pipes paying special attention to any joins for signs of leaking water.

Repairing the pipe will depend on how the pipe is sealed. You may need a wrench or have to use a sealant.

4. Loose Bolts

Your toilet should be firmly fixed to the floor with 2 bolts. You may not be able to see these directly as they often have a cap that covers them.

Carefully remove the caps and then tighten the bolts. The bolts tighten the seal between the bottom surface of the toilet and a wax seal. If these bolts are loose then the seal between the toilet and the floor is less effective and water will escape under pressure such as when flushing.

5. Worn Wax Ring

What you are learning here about identifying the source of leaks applies to many other plumbing jobs in the home. Often, it is a logical process of elimination.

For example, if having already tightened the floor bolts you are still getting a water leak when flushing the next logical culprit is the wax seal ring.

Sometimes it is both the floor bolts that have loosened and the wax seal ring has deteriorated. Some toilet chemicals put into the toilet can damage the seal.

The good news is that replacing the seal ring need not be a complicated job or expensive.

6. Porcelain Potty

Most toilets are cast in porcelain. This is an imperfect material and even though it looks clean and nice, sometimes there can be small sand holes in the toilet basin. This will leak every time the toilet is flushed.

This can be a very frustrating problem as it may not be easy for you to spot. You can waste a lot of time trying to track down the cause of your leak but really it is coming from your basin.

Of course, if you use a professional they will always be on the lookout for irregularities like this, especially if all other causes have been ruled out.

Why Is My Toilet Leaking at the Base? Now You Know

You do not need to wonder why is my toilet leaking at the base. In this article, you have read about the most common causes and even one less so common cause.

Most remedies are quite easy but you may prefer a professional to handle the matter. Don’t forget if your toilet is leaking you should stop using it straight away.

If you are thinking about using a professional then perhaps you are wondering about how much it would cost. Check out this article here to give you some ideas.

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1 Comment
  1. Sandra westbrook

    Should I just turn water off at toilet tank until I can get a plumber since it is leaking from underneath the seat base?


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