Should you put silicone over grout?

You may have heard of using silicone to go over grout. What’s the advantage? Why would you do it? We’ll explain everything you need to know about this topic, including why you’d want to use silicone caulk in your kitchen or bathroom, how to prep for the project, and how to best take on the job.

As a general contractor and handyman, I’ve been doing caulking jobs for people for years. And a recent job inspired this article: A woman called me about installing some new floor tiles in her house.

When we were talking about the project’s details she suddenly asked if I could seal her grout lines after the installation was finished.

I wasn’t expecting that request – it’s not something I’ve done before! But when I thought about it, it made sense: Silicone will help your grout with water resistance and protect against mold growth.

So even though there are some challenges involved with this approach (for example special considerations are necessary when using dark-colored grout), I went ahead and did it…and now my clients have some beautiful new floors!

Do you need silicone over grout?

In most cases, the answer is no. The only reason you would need to use silicone over grout is if it’s not properly sealed.

If your grout isn’t properly sealed, then moisture and other elements will be able to penetrate it and compromise both the look and function of your tiling work.

A lot of people ask me whether they should use silicone over grout, so I thought I’d take a moment to explain what you need to do instead of using silicone over grout:

  • You need to seal the grout with a specialized product. Grout sealers come in various types, each suited for specific projects or specific types of grout.
  • There are several main types of grout sealers on the market: Water-based, solvent-based, epoxy, penetrating, and color enhancing sealers. You may want to consult an expert about which type is best for your project (for example, you don’t want to use clear epoxy on white tiles) as well as how much coverage you’re going to get per application. In many cases, two applications separated by at least 24 hours is necessary for full protection.
  • There are also some non-traditional ways that people have tried sealing their tile work in order to avoid using silicone over grout. Applying a stain such as concrete stain has been used by some DIYers with good results; however, this method can only be used with certain types of tile (concrete or similar materials). Other methods include using epoxy floor paint or even using spray foam insulation! This last method seems pretty crazy but apparently works great!

Can I apply silicone on grout?

Although it is tempting to apply silicone over grout, this is not the best idea. Here are a few reasons why:

  • Grout lines are too narrow to allow enough silicone to bond properly, causing the silicone to fail.
  • Silicone will not adhere well to grout, resulting in a poor seal between tiles or fixtures.
  • Even if applied correctly, silicone is prone to collecting dirt and mold over time due to its porous nature—this problem would be exacerbated by applying it over textured grout lines (which can be quite impossible with many types of tile glazes).

Can you seal over grout with silicone?

There are a few ways to seal over grout with silicone. You’ve come to the right place if you’re wondering how. It’s actually quite simple. You won’t even need any tools beyond your hands, a sharp knife, and some tape or masking paper.

If you want to remove the silicone, you’ll want to do it before resealing as well because any residue might affect the result of your new sealant.

Here’s what you need for sealing over grout with silicone:

  • A roll of masking tape or painter’s tape
  • A sharp knife (like a box cutter)
  • Some old rags or paper towels

Do you seal grout before silicone?

No. Sealing grout before silicone is not necessary. In fact, there are some good arguments as to why you shouldn’t seal it first. And here they are:

  • It will give your tile a dirty look.
  • You’ll be wasting your time and money! Silicone is meant to displace water and keep water out of the walls, so sealing grout before applying silicone is redundant and a waste of time and money.
  • It’s really difficult to clean up the silicone after you’ve applied the sealant to the grout – unless you’re using a wipe-on product that has been specifically formulated for this purpose, cleaning up any messes will be nearly impossible without ruining your entire project in addition to ruining any wall or floor tile work you may have already finished applying!

Can you put grout over grout?

No, you definitely should not put grout over grout. Grout is typically made of a mixture of sand and cement. If you place new grout on old, the two layers will be bonded only by their outer surfaces.

There will be no real connection between them because there’s nothing to hold them together. To repair a mistake or replace broken tiles you need to remove existing grout, clean it, and then re-grout.

If your grout is in good condition but has lost its color (it happens) or if you want extra protection against water damage, then you can apply a layer of grout sealer over your existing grout. You do this with a fine brush or spray bottle and allow it to dry before applying another coat.

Do you grout first then silicone?

The answer? It depends.

  • If the silicone has been applied first and the grout is brushed onto it, the silicone will stick to the grout but not vice versa. That’s because silicone repels water and since there’s already a layer of silicone on top of the tile, the water from the grout won’t be able to seep into any small grooves in your tiles.
  • On the other hand, if you apply a layer of grout first, then put down a layer of silicone on top of that, you’ll have a slightly different experience: this time around, both substances will stick to each other with ease.

Do you grout or silicone shower corners?

When you’re remodeling your bathroom and installing a new shower, it’s important to seal the shower with silicone.

There are several places where silicone is used; one of the most important areas is around the shower corners. Silicone seals and waterproofs these corners, preventing water from leaking through and causing damage to your home.

In addition, you might have to replace some of your grout in the shower area as well. The caulking in a shower will also need replacing over time due to regular exposure to moisture.

Should you remove grout before caulking?

The fact is, nothing adheres to grout not even another layer of grout. Grout is so porous, in fact, that it acts essentially like a sponge and will soak up any material you apply to it.

Even if you’re able to apply the caulk over the grout, the surface is still uneven and rough enough that it won’t form a tight seal with the wall or floor.

This means that water will seep under the caulk and get into your walls or floors, causing more damage as well as mold and mildew growth.

Instead of masking these problems by applying caulk directly over grout, take on some DIY tile repair projects to solve them instead!


To summarize, silicone caulk can be used over grout in the shower, but only when grouting tiles. This is because silicone caulk works best for sealing and waterproofing, whereas grout doesn’t provide enough of a seal to prevent water from seeping into your walls.

If you are going to use silicone caulk over grout, you should apply it after the grout has dried (usually 24 hours after being applied).

You don’t have to seal your tile as long as it is glazed; if it isn’t, you should seal the tile first and then apply your silicone caulk over the grout.

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Martin Flood

Martin Flood has been working in the construction industry for over 20 years as a general contractor with expertise in remodeling projects that are large or small. He has furthered his career by specializing in epoxy resin flooring, providing excellent service to both commercial and residential clients. Martin’s experience enables him to offer professional advice on how to choose the right type of project based on your needs and budget.

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