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Can You Use Mastic In A Shower?

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Mastic is helpful in many ways. You are probably wondering whether or not you can use mastic in the shower. Look no further! We have researched all about mastic and how it fairs around water for you.

You can use mastic in the shower but only in small amounts and not on the floor of the shower. Mastic does not do well when it gets wet.

If you still have some additional questions, don't worry. In this post, we'll discuss the topic in more detail. Keep reading to learn more about what happens to mastic when it gets wet, whether or not it is better than thinset, if you can use mastic to tile shower walls, and more. Mastic advantages and disadvantages when used, Can you use mastic in a shower?

All About Mastico

Mastic a sealant or adhesive used in construction projects

Mastic is used as a sealant and adhesive during construction projects. One popular use for it is to hold up tile because it has superior strength. It does not fair well when it gets wet, so it's best to use it for kitchen tile or floor tile in areas that will not get wet.

Something important to understand about mastic is that it is premixed. The reason this is important is that it helps work be completed faster, but faster is not always better. Consider whether or not the mastic is going to get wet.

What happens to Mastic when it gets wet?

When mastic gets wet, it has the potential to emulsify. What this means is that it disintegrates, which completely defeats the purpose of using it.

If the bond weakens, the tiles will fall and break, which means the project will have to be done again. This is a hassle because you do not want an area like your bathroom to be out of order for any longer than it has to be.

Thinset, also known as mortar, can withstand water, so it is the better choice when it comes to areas that may become wet. A bathroom is an example of the most common area in the house where you have to deal with moisture.

Sometimes people still use mastic in the bathroom even though it comes with risks. The reason people choose to do this is that it takes less time than mortar, but that does not make it the best choice.

Click here to see this premixed mastic on Amazon.

Is there a waterproof mastic?

There are mastic waterproof coatings available. These can be sprayed or rolled onto the surface you are coating. These mastic waterproof coatings are ready to be used and stop water from seeping into the tile or whatever you are working with.

Cured mastic still emulsifies when water comes into contact with it. Thinset, on the other hand, is not affected by water once it is cured. Look at the product description on the packaging or the back of the tub to see if what you have is waterproof.

Is Mastic better than Thinset?

Differences betwen mastic and thinset

Mastic is better than thinset in some aspects but not all. Mastic and thinset are different in a few ways. Thinset is better than mastic in that it is more structurally sound. Another way thinset is actually better than mastic is that it is waterproof, unlike mastic.

One benefit of using mastic is that it is long lasting, so you do not have to worry about it going bad if you do not use all of it at once. You can easily come back to finish your project later if you need to take a break. Mastic does not dry nearly as fast as mortar or thinset.

You can find mastic at just about any home improvement store, and it does not require mixing. It is better in the sense that mastic is ready to use upon purchasing it. This saves you time and is more convenient to use when you are ready for it.

More to Consider

It is important to understand that mastic has a tendency to turn yellow once it has dried. If you use it to put up a clear backsplash, the yellow tint will probably come through which will affect the overall look. Keep your eyes out for a backsplash that has a backing on it or one that is not clear to avoid this issue.

Click here to see this mastic for ceramic tile on Amazon.

Thinset takes longer to set than mastic. When you are working on adhering tiles to a floor, thinset taking longer to set gives you the advantage of being able to fix any tiles that are not straight. You have the chance to fix it before it dries.

Mastic dries more quickly and is better for vertical applications such as the backsplash in your kitchen. If you use thinset for a vertical application, the tiles might sag.

Can you use mastic to tile shower walls?

Mastic on walls is recommended but not on floors

You might see the manufacturer of mastic state that it can be used on the walls of a shower but not on the floor. This is because the floor is much more likely to get wet than the wall. Humidity in the bathroom is still a factor to consider though.

Technically, you can use mastic if you are going to be placing a small area of tile on your shower walls, but there is a better alternative. The shower walls would work better with mastic than the floor of the shower will.

Mastic sets quickly and is easy to apply, so it is okay to use for tiling shower walls as long as you let it dry completely and do not use an excessive amount.

Although you can use mastic to tile shower walls because it is extremely strong, it is not the very best choice to use for tiling shower walls. It is said to be okay to use in areas with light moisture, but a shower is not a light moisture area. Epoxy mortar or thinset mortar are better alternatives.

Here is a link to learn more about shower tile adhesives:

What Are The Best Shower Tile Adhesives?

Is Mastic good for kitchen tile? Applying mastic in kitchen tile and any other not enclosed space

Mastic can be used to put up tile in your kitchen because it is not an enclosed space like a bathroom. The humidity in the bathroom that builds up when someone takes a hot shower is enough to make you think twice about using mastic to tile the walls in your bathroom.

The moisture in the air will go through grout and then behind tiles (which are porous), and then you will be facing problems.

If you are determined to use mastic in your bathroom because it is more convenient or whatever reason suits you, then be sure to put up drywall that is water resistant.

With this in mind, using mastic around the bathtub or shower is not the best option. Thinset is waterproof, so it is the better choice when it comes to tiling the walls of a shower.

Will mastic stick to Redgard?

Mastic does not stick to Redgard very well. If you try to use mastic, the tiles will most likely fall off. Mortar that is not premixed will bond better. 

How long after mastic can I grout?

The answer to this question depends on the type of mastic that you use as well as the surrounding environment. Somewhere with more humidity will take longer to dry or set up before you can grout. In general, mastic takes about two or three days to become cured.

It is best to wait three days after using mastic before you grout just to be sure it has cured. If you do not have that long to wait, then two days is probably sufficient. Consider where you live and what the climate is like before making the final decision.

If you are looking for a fast-setting adhesive, you can buy thinsets that set up within two hours. In this case, you do not have to wait as long as you do with mastic before grouting.

Please consider what will happen if you grout before the mastic is dry. The tiles or backsplash you are trying to work with might come loose and fall which will cause them to break if you try to grout too soon.

Mastic needs to be fully cured before you can grout no matter if the project you are working on is inside or outside.

In Closing Mastic advantages and disadvantages when used, Can you use mastic in a shower?

All in all, mastic works best in dry areas. You can not use mastic in a shower unless it is for a small area of tiles on the shower wall.

Even still, it is not the best choice for areas with high amounts of moisture because it is likely to emulsify if it comes into contact with water. Mastic works best as a sealant and adhesive when it is adhering to something that will not get wet.

Before you go, check out the following links related to putting up tile:

How To Remove Thinset From Tile [2 Methods]

3 Types Of Tile Glue To Know