How to Seal Porcelain Tiles: The Complete Guide

Thanks to their smooth, non-porous surface and durability, porcelain tiles are a staple in kitchens, showers, bathrooms, and public spaces like lobbies and hallways. It’s a significant investment, and you may want to protect it by sealing it.

One of the most important steps in maintaining your porcelain tile is sealing the tile and grout you’ve laid it with. This process requires preparatory cleaning, the application of the sealant, and allowing it to dwell for multiple stages. You should also consider carefully what sealer you are using.

However, sealing porcelain is not a simple task. You need to be meticulous at every step. Additionally, there is a lot to consider before diving headfirst into it, such as whether you even need to seal your tile in the first place. To cover everything you need to know, here is a complete guide to sealing porcelain tiles.

Steps to Seal Porcelain Tiles

To ensure you properly preserve your porcelain tiles and grout, you should apply some form of sealant to the tile, whether it be in a bathroom, kitchen, or outdoor setting. This is a relatively straightforward process. Here are the steps:

• Start by cleaning the tiles and grout, either with a vinegar-water mixture or a commercial cleaner. Be sure to remove any loose dirt.
• Apply the sealant using a cloth or applicator. Be deliberate and work on one small area at a time. Don’t forget about the grout.
• After allowing the sealant to soak into the tile for a few minutes, wipe off any excess sealant. If you find the tile to still be tacky, apply a bit more, don’t let it dwell for longer than three minutes, and then wipe off the excess sealant.
• Allow the sealant to cure in the tile for approximately an hour. The tile will not be fully load-bearing for at least a day but can be used sparingly.

Like with many things, there are some important tips to consider at each step: how to properly clean the tile in the first place, how to apply the sealant, etc. Let’s break down each step.

Cleaning Porcelain Tiles and Grout

It is crucial to clean your porcelain tiles and grout before applying the sealant. Skipping this step could seal existing dirt and stains into the tile. Cleaning methods vary slightly depending on the type of porcelain tiles, but they generally follow this basic format:

• Remove loose dirt by sweeping or vacuuming
• Scrub with a cleaning solution (brand-specific, be sure to scrub problem spots!)
• Rinse off the solution
• Allow it to dry

You can concoct a suitable cleaning solution for porcelain tiles at home. Simply add ¼ cup of vinegar to 2 gallons of water. You can also use any multipurpose cleaner that you would use on countertops and other floors.

However, if your tile is rather stained, you may want to consider a commercial heavy-duty product. Be cautious about what solutions you use; aggressive chemicals like acid or ammonia can permanently damage your tile if it is glazed or polished. Here are some good, non-damaging options:

• Miracle Sealants Tile & Stone Cleaner
• Black Diamond Stoneworks Marble & Tile Concentrated Cleaner (also consider Black Diamond’s intensive solution for a more thorough clean)

Some cleaning products come with a scrubber or applicator that makes it easy to work on heavily soiled spots of your tile. If you’re sticking with vinegar and water, a mop will do just fine.

Since you’re already cleaning the tile, it might be good to spend some time on the surrounding grout as well. Thankfully, most cleaners and sealants work well on both tile and grout. However, if you notice grout haze (more on that later), there are specific cleaners you can use:

• Grout-EEZ Grout Cleaner & Brightener
• Aqua Mix Grout Haze Clean-Up
• Zep Grout Cleaner & Brightener

After you’re done scrubbing or washing your tile, be sure to rinse off and allow the porcelain and grout to dry. Consider mopping up or wiping away any excess water to speed up drying and prevent water damage.

Applying the Sealant to the Tile and Grout

Now that your tiles and grout are clean, it’s time to apply the sealant. A cloth or brush is a good household tool for spreading the sealant. You can also purchase an applicator that resembles a squeegee. An applicator can minimize mess and ensure an even layer of sealant.

How Much Sealant Do You Need?

Typically, you’ll need a 32-ounce bottle of sealant if you’re working on a kitchen or bathroom floor. However, it may be wise to have a larger container if you expect your tiled space or area to be heavily utilized.

When applying the sealant to the tile, pour some into a smaller container to use from rather than pouring it directly onto the tile. This container could be a cup or tray; just make sure your cloth or applicator fits inside.

The trick to applying the sealant is to work in small areas. You don’t want to apply a lot at once, as you would with a cleaning solution. Instead, concentrate on one tile or a few at a time if your tiles are smaller. Gently go over an area, then allow it to dwell for a few minutes, no more than five.

Don’t forget to spend some time on the grout as well. A cloth or brush can be helpful for the mortar if you’re having trouble using the applicator. Just be sure to follow the same method as with the tiles: apply in small doses and let it dwell for a few minutes.

Wipe Off Any Excess Sealant

After allowing the sealant to dwell for a few minutes, take a clean, dry cloth and wipe off any residue of the sealant from the tile and grout.

If you let the sealant dwell for too long, the tile may become tacky. In this case, do not apply water or a cleaning solution to wipe it off. Instead, apply a bit more sealant; just be sure to let it dwell for less time than your initial layer. Then, wipe away any excess sealant.

Wait Approximately an Hour

Although you have already removed the excess sealant before wiping, it will still take some time for the sealant to fully cure. As the sealant cures, it fills or coats the minuscule pores in the tile. You should wait approximately an hour before stepping on the porcelain or using the area where it is installed (e.g., a shower).

For high traffic, you may want to wait much longer, even up to three days. If the tile is in a heavily trafficked area, like a hallway or a public bathroom, continuous use could negate some of the effects of the new sealant or embed new dirt.

If you have followed these steps: Well done! You now have porcelain tiles and grout protected against stains and even more resistant to water damage than before. It is now even easier to clean:

• Floors
• Bathrooms
• Patios

How to Determine If You Need to Seal Your Porcelain Tile

Before proceeding with any of the above steps, you must determine if you even need to seal your tile at all. To do this, you need to identify what type of porcelain you have. It also helps to know why some types require sealing and others do not. This can aid in selecting a sealer. We’ll delve into that later.

Porcelain tiles fall into two categories, glazed and unglazed. There are also two subcategories for unglazed porcelain: polished and unpolished.

Glazed vs. Unglazed

Glazed and unglazed porcelain are made practically the same, except for one additional step. The porcelain is made by compressing clay, silica, and other materials at extremely high temperatures. This compression is one of the reasons why porcelain is more water-resistant than other materials.

Here’s where the two types differ: Some tiles receive an additional layer of glass (the glazed tiles), and others do not (the unglazed tiles). This layer of glass protects glazed tiles from stains, so they do not need to be sealed.

Glazed tiles tend to be slightly thinner and less dense than unglazed ones. They weigh less and are often less expensive in manufacturing or installation. Conversely, unglazed porcelain tiles are more slip-resistant since they lack the top layer of glass, making them ideal for high-traffic areas. For this reason, they also work better for bathroom or shower floors.

Since glazed tiles contain the extra defense layer, they are less likely to get discolored. Unglazed ones are, which is important when they get scratched – chips or scratches will be less noticeable since the underlying layer matches the surface. The less refined surface of unglazed tiles also makes them appear more natural, earthy, or rustic like stone tiles. That makes them ideal for outdoor areas like patios.

Glazed tiles do not need to be sealed, although it doesn’t hurt. Additionally, you should still seal the grout to prevent mold if this tile is being installed in a high-humidity area, such as a bathroom.

In the meantime, some unglazed tiles should be sealed if you want to prevent them from staining or trapping dirt. There are two types of unglazed tiles that require further consideration before using a sealant.

Polished vs. Unpolished

Polished porcelain tiles are unglazed but have the same look and sheen as glazed tiles. This is because these tiles undergo an additional step in the process: surface grinding. It’s similar to sanding something to achieve a smooth surface, but it does create tiny, invisible pores in the tile that can trap mortar and dirt over time.

Unpolished tiles skip this grinding step, which gives them a more textured feel and helps them stay waterproof. However, they are still more prone to staining since they are not glazed.

It’s important to note that not all unglazed porcelain tiles that are textured or matte are unpolished. Depending on the manufacturer, there may be additional steps that give your tile an appearance that reveals what type of unglazed porcelain tile it is.

If you’re unsure what type of tile you’re considering or have already installed, perform a water absorbency test. Just let a few drops of water sit on a tile and observe after a few minutes whether it has soaked into the tile or not.

Don’t Forget the Grout

Grout is the applied substance between the tiles. It seals the gaps between tiles (porcelain and other types) to prevent the following from accumulating beneath:

• Moisture
• Dirt
• Mold

Since grout is visible, it is also an essential component of your tile’s aesthetics. Caring for it is almost as important as the tile itself.

When applying tiles and grout to a floor in your kitchen or bathroom, you can use sanded grout. It’s affordable and works well with wider gaps between tiles. It’s also available in various colors.

However, unsanded grout is more durable and may even come pre-sealed, depending on the brand. It can be used in any environment and suits porcelain tiles better as there is less chance of scratching the surface. It is also more expensive than sanded grout and doesn’t perform as well with wider gaps between tiles.

You may notice residue grout on the tile. That is mortar haze, which is leftover material from when the mortar and the tile were laid. This can affect the overall appearance of your tile, but it can be removed with some cleaning products.

Tips for Choosing and Using a Sealer

Assuming you find that the tile needs a layer of sealant or you want the extra protection, you now need to select a type of sealer. There are many options to choose from, and some offer better protection for your tile than others.

What Type of Sealer Should You Use?

To get the best protection for your tile, the sealer must complement where you have installed the porcelain. When it comes to sealing porcelain tiles, you should stick to two types of sealers:

• Penetrating
• Topical

Penetrating or impregnating sealer is good for porcelain tiles, especially unglazed ones, but it will not ruin glazed tiles if you choose to apply it. When you do, the sealer cures and soaks into the tile, filling the microscopic holes without altering the appearance or slip resistance of the porcelain.

Most penetrating sealers are solvent-based. This composition allows the sealer to saturate denser tiles like porcelain and granite more readily. It also holds its layer more firmly, making it a better protective solution than some conventional water-based products.

One of the most commonly used penetrating sealers is Miracle Sealants’ 511 Impregnator, which provides stain and water protection while preserving the slip resistance of porcelain. It also works on grout and stone materials like granite, polished marble, and slate.

Other penetrating sealers should work as well, including:

• Mapei Ultimate Penetrating SB Stone, Tile, & Grout Sealer
• GlazeGuard Gloss Ultra Durable Ceramic Sealer for Porcelain Tiles, available in high-gloss, satin, and matte finishes
• Custom Building Products MORTAR, CERAMIC & PORCELAIN WATER-BASED SEALER
• FILA Surface Care Solutions MP60 Eco Plus High-Performance Penetrating Sealer, also water-based

Epoxy or topical sealers are somewhat inferior to impregnators. Typically, these are used to clean or fix tiles that have become damaged or worn over time. With porcelain, floor finishes don’t adhere well to new polished tiles.

If you do decide on this type of sealer, you’ll want a higher-grade brand like Aqua Mix High Gloss Sealer. It protects the tile while giving it lots of shine, so it works well with polished porcelain tiles.

Using an ineffective sealer will most likely have no lasting effects on the tile that you can’t