Is Bathroom Grout Waterproof or Porous? Do You Seal It?

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Grouting of tiles.

It goes without saying that tiling the bathroom will take up a lot of your energy, time, and patience. That said, the results are well worth it. Along with tiling, there is also the need to grout the bathroom floor and wall tiles to prevent water from seeping into the gaps. However, is grouting genuinely essential? Isn’t grout porous, and as such, won’t provide adequate waterproofing? 

There are different types of grout, and depending on which one you use will determine whether it is waterproof or porous. The most commonly used grout, the cement-based, is porous and will require an additional sealant. Other grout types, such as acrylic is waterproof but still needs a water-based sealer, while the epoxy-based are 100% waterproof. 

Also, depending on where you need to apply grout will help determine which type of grout to use. In this article, we will explain the main differences between the three grout types and the pros and cons. 

Why Is It Mandatory to Seal Your Bathroom Grout?

Besides the fact that it will improve the overall waterproofing of your tile floor and wall and lower the risk of water damage? Grouting is pretty cheap, and it is also relatively quick and easy to do. Therefore, there is no downside to grouting your bathroom tiles as the advantages far outweigh the perceived drawbacks. 

Different Types of Grout

You will encounter three different types of grout in the market. Understanding the pros and cons of each will help you determine the best course of action in your home improvement endeavor.

Cement-Based Grout

The cheapest and most commonly used type of grout is the cement-based one. The cement-based grout is porous, so it is mandatory to apply a sealant. This type of grout comes in both sanded and un-sanded variations. Sealing it is crucial; otherwise, it is highly susceptible to water stains and cracking. 

While it certainly has the biggest drawbacks, these flaws can be resolved relatively quickly and cheaply, as well. Cement-based grout can dry within 24 hours, and sealing it immediately afterward is crucial. 

Acrylic-Based Grout

Acrylic-based grout has a similar appearance to caulk with its smooth finish. However, unlike cement-based grout, the acrylic version does not require any prior mixture before using and can be applied right out of the jar. Acrylic-based grout also requires about 24 hours to dry but will need an extra three days before it is fully waterproof.

While acrylic-based grouts might sound perfect, they come with some notable downsides. One of the most significant drawbacks of acrylic grout is that it is susceptible to expanding and contracting, increasing the chances of it cracking. 

While considered waterproof, most experts still highly recommend applying sealants over acrylic grout for additional protection. 

Epoxy-Based Grout

Epoxy-based grout is considered the toughest option available. It is also incredibly resistant to stain, chemicals, cracks, and weather conditions. Additionally, newer epoxy grout products are non-toxic and are environment-safe. 

The overall quality delivered by epoxy grout comes at a price, though. Literally, this is the most expensive type of grout. However, the significant increase in the cost means that your home will have the most durable and reliable tile grout available. 

Different Ways to Seal the Grout

Fortunately, grout sealing is relatively easy, no matter what type of grout you will be using for the job. Below are methods on how you can seal the grout in the shower. 

Using a Brush

This method is pretty straightforward and will require a small brush tip that you can get at your local hardware store or the arts and craft aisle. However, remember that using a brush to apply a sealant to the grout will demand absolute precision.

The last thing you want is to accidentally apply the sealer to the tile, as it will leave a stain if it does. Small spots are okay, but make sure to quickly wipe them off if you accidentally applied sealer over the tile. Also, this technique is the most tedious way to go about this task. 

Using a Roller

If the time-consuming method of brushing the sealant gave you pause, then we have a piece of good news for you. The roller method is the easiest way to seal over the grout. Using an appropriately sized roller pretty much eliminates the risk of accidentally spilling over the sealant over to the tiles. 

Using a Spray

If you are looking for the fastest method, the spray-on will deliver that result. The downside of using a spray is that it is not the most accurate technique to apply the sealer. In addition, you will need to wipe down the edges of the tiles to prevent stains from appearing.

Guidelines to Follow Before Applying Sealant to the Grout

Like any other chemical, sealants must be handled with care and a good grasp of using it. Here are the steps to properly apply a sealant to the grout. 

Step 1: Clean the Grout

Person Cleaning The White Tile Using Brush

This is vital to ensure that the sealer will adhere to the grout properly and create a waterproof seal. Next, pour water and scrub the grout thoroughly using a scrub pad or toothbrush, making sure to remove all dirt and debris. Once done, leave the floor to dry, which should only take under an hour.

Step 2: Apply the Sealer

We have gone through the different types of grout, but did you know that there are also other types of sealers? There are two main types that you can use, and here is a summary of each sealer:

Penetrating Sealer – This type of sealer utilizes water-based formula, which allows it to seep into and penetrate the grout completely.

Membrane Forming Sealer – The membrane forming sealer hardens and creates a coating over the surface of the grout. It is generally not recommended for bathroom use as this type of sealer does not provide adequate waterproofing in high moisture areas. 

Step 3: Applying the Grout

worker with rubber trowel applying grout tile

First thing’s first, wear rubber gloves when handling chemicals such as sealers as they can irritate your skin. Next, please choose how to apply the sealer (the roller is our recommendation). Finally, be careful not to apply sealers to the tile. If you do, make sure to wipe it immediately. 

Please leave it to dry and then apply the second coating. Apply a third coating if necessary. You can tell that the grout is fully waterproof if water beads slide off of it rather than being absorbed. 

Frequently Asked Questions Regarding Grout and Sealers

How Long Does it Take to Seal the Grout?

You can only start applying the sealer if your grout is fully dry and ready for curing. The period required for this tends to be around 48 to 72 hours. It will also depend on whether you will be using water-based or solvent-based sealers. Water-based dry faster while solvent-based are longer lasting and more durable. 

How Much Grout Sealer Will I Need? 

You wouldn’t want to run out of grout sealant halfway through the job, right? In general, a one-quart container of grout sealer is enough to cover a 200-square feet floor with a standard 12-inch tile. Remember this before heading off to your local hardware store to buy a sealer. 

How Often Should I Grout My Bathroom Tiles?

Ideally, you should apply a sealant on your grout once every year. Sure, most sealers claim to last long, but you have to consider the cleaning chemicals that come into contact with it throughout the years. These chemicals can degrade the integrity of the sealer; hence, it is recommended to reapply a fresh coat once every year. 


Bathroom grout is generally cement-based due to it being cost-effective. However, the cement-based grout is porous and will need extra help from a sealer to make it waterproof. The sealer is a crucial element in grouting unless you have epoxy-based grout, which is already waterproof and considerably more durable.