How Do You Seal the Base of a Toilet?

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One of the biggest tasks when it comes to fitting a toilet in your home is sealing around the base.

There are lots of different options to choose from which can result in it being difficult to decide which is the best for your home. But once you decide which materials to use, then sealing around the base of your toilet is a fairly easy task.

All you really need to do is use your chosen materials and fill the gap between the bottom of your toilet and the flooring.

Most sealants come in a tube which allows you to simply squeeze the material between the gaps, preventing any liquid from getting underneath the toilet to space where you will be unable to reach it.

We’ve covered how to seal the base of a toilet, but there are lots of other things you need to know before you get started. So let’s take a look at the other things you need to know about sealing your toilet.

Should you grout or caulk around a toilet?

Before you start sealing the base of your toilet, you need to decide which materials to use. Generally speaking, you have two options to choose between: grout and caulk. So which one is the better option?

You can use both caulk and grout to seal the base of your toilet, and which is the best for you will depend on what you want out of it. If you want to be able to get the job done quickly then caulking around the base of your toilet is probably the best option. Whereas if you want your toilet to be better supported then grout is the better option.

Something else that makes some people choose grout over caulk, is that it is easier to remove grout in the event of a leak inside of your toilet. Whereas if you seal all around the toilet with caulk then you might not be easily able to access the leak and fix it.

However, some people work around this by leaving a gap in the caulking at the back end of their toilet so that it can be easily accessed should a leak occur.

How do you caulk around the bottom of a toilet?

Now that we have covered that you can use either caulk or grout to seal the bottom of your toilet, let’s take a more specific look at how you caulk the base of your toilet.

Most caulk mixtures that you can buy will come with something known as a caulk gun. If your caulk did not include this, then you can get one of these devices in most hardware stores.

The caulk tube fits snug inside of the gun and allows you to discharge caulk from the tube when you pull the trigger of the gun. This makes applying the caulk a lot easier.

With the caulk fitted inside the gun, you should begin pulling the gun along the joint between the bottom of the toilet and the floor. While doing this, you should pull on the trigger of the caulk gun, and keep the device at a 45-degree angle for the best results.

You should maintain constant pressure on the trigger to ensure that the amount of caulk that discharges from the gun does not differ at any point in the process. This is the only way that you will be able to get even results. You should also move slowly to achieve a perfect finish in the seal between your toilet and the floor.

Why is the grout around my toilet wet?

If the space between your toilet’s base and the floor is already sealed then you might observe that it has become wet. This is most common if the seal has been completed using grout, but what is it that causes this? Let’s take a look.

Most commonly, wetness on your grout is caused by condensation. Generally, your toilet and the sealant that attaches it to the floor are cold, so when warm, moist air comes into contact with this it can cause the toilet to sweat . This is because the water moisture in the air has attached to the toilet and turned to actual water.

It is very common for you to observe wetness on the outside of your toilet and in the grout after you have a shower or a warm bath in the same room. This is because the warm water that runs in the bath/shower will release warm moisture into the air, which will then come into contact with the toilet/grout and make it wet.

So if you observe wetness in your grout, then there’s no need to panic immediately as this is most commonly caused by condensation.

Which is better wax or rubber toilet seal?

Finally, let’s talk about toilet seals. A toilet seal isn’t necessarily the same as the action of sealing around the base of your toilet.

Instead, these seals that we are talking about are placed into the floor before the toilet itself is fitted, and they work to provide an airtight seal between the drainage pipe and the floor.

There are mainly two options that you have when it comes to this type of toilet seal, they are wax or rubber. Traditionally, wax would be the only option, and this is why a lot of people tend to stick with this type of seal, but depending on your home it might not be the right choice.

For example, if you have underfloor heating then a wax option might not be the best choice as it will become disfigured when it gets warm. Alternatively, if you are replacing the seal of your toilet yourself you might choose a rubber option as they are easier to work with than wax.

So neither a wax nor a rubber toilet seal is necessarily the best, instead, it depends on your situation and which is the most feasible option for you.


In short, sealing the base of your toilet is a surprisingly easy job, and it is usually done using grout or caulk.

Both options are excellent but the right choice for you will depend on your situation and your needs.