Tiling 101: What Is Grout?

When you think of grout, you probably imagine labor-intensive scrubbing between tiles to get kitchen floors or shower walls clean. But what is grout actually used for (besides adding yet another task to your spring cleaning checklist)? Grout is an important component for tiling, especially if you want your tiles to remain in good condition for as long as possible. Let’s explore the ins and outs of grout, from what it does to the different types and more.

What Is Grout and What Is It Used For?

Grout is made from a mixture of ingredients with a base made from either cement, known as cementitious grout, or resins, known as epoxy grout. From there, manufacturers mix the cement or resin with other materials, like silica, sand, water, or hardeners, depending on the type of grout. 

So now you know what grout is made from, but what’s the purpose of grout? This material acts as a filler to place between tiles. After application, grout takes 24 to 72 hours to dry and cure. This allows the grout to form a hard surface that prevents water or debris from getting behind tiles and causing a moldy mess. Grout also helps prevent tiles from separating from their adhesive that attaches them to walls and floors.

Common Types of Grout

There are many types of grout available today, but two of the most common options include cementitious grout, available sanded or unsanded, and epoxy grout. Different types of grout may work better for certain projects, and you may also consider different grouts depending on whether you’re DIYing tile and grout installation or hiring a pro.

Cementitious Grout

Cementitious grout is a grout made from cement as the base. This grout has slightly more flexibility, meaning it can reach deeper crevices between tiles than epoxy grout. It’s also easier to work with than epoxy, making it more DIY-friendly. However, cementitious grout is more porous, making it vulnerable to excessive moisture and staining.

Cementitious grout comes in two options: sanded or unsanded.

Sanded

Sanded grout is made with cement, water, and sand to create a highly durable grout that better resists shrinking. Because it’s so strong, sanded grout is often recommended for flooring and high-traffic areas. Plus, sand is a low-cost filler, so sanded grout is often less expensive than other grout options.

Sanded grout has a gritty texture, so it may scratch certain tile materials, like marble or glass. It’s also porous and vulnerable to staining, so be sure to add a sealant after applying sanded grout.

Unsanded

Unsanded grout is one of the easiest grout types to work with, so if you plan to DIY new wall tiling on a mudroom wall or behind a bathroom vanity, this option may be your best bet. It’s made with cement, water, and aggregate materials rather than sand, lending it a stickier texture that dries down smoothly.

The sticky yet smooth surface makes unsanded grout great for applying tiles on a vertical surface, like bathroom walls or kitchen backsplashes. It’s also perfect for use with more delicate tiles that would scratch easily, like ceramic or marble tiles.

Epoxy

Epoxy grout is a resin-based option that offers the benefits of being waterproof and mold- and mildew-resistant. Plus, it comes with more consistency in color and is less likely to stain than cement-based grout. Because of the added hardeners, epoxy is extremely durable, making it a good choice for high-moisture areas and high-traffic floors, alike.

However, epoxy does have some limitations. Epoxy grout costs $8 to $12 per square foot, while unsanded grout costs around $5 to $6 per square foot. Mixing epoxy involves a chemical reaction that makes the mixture harder, and if you don’t apply it quickly enough, it can become too hard to apply. It’s best to pay for a pro to handle epoxy grout.

Choosing Grout Colors

No matter what type of grout you want for your tiling project, you’ll find a wide range of grout color options. There are pros and cons to lighter grouts versus darker grouts to consider when finalizing your grout purchase. For instance, lighter grouts can create a seamless look with lighter tiles, but they can also show stains more easily. Darker grouts blend well with darker tiles or add contrast to lighter-colored tiles, but they are prone to fading.

Ultimately, finding the right grout color will depend on your personal design preferences, but you can consider adding sealant to better preserve the look of whichever grout you choose.

Does Grout Need Sealed?

If you opt to use cement-based grout for your tiling project, you’ll also want to budget for grout sealant. Epoxy grout is waterproof, so it doesn’t need sealing. Sealing grout helps protect it from moisture, which can be especially important for more porous types of grout or grout applied in high-moisture areas like kitchens and bathrooms. Sealants can better protect grout from water damage and staining.

You’ll need to apply sealant after installing tile and grout, then reapply sealant to the grout every two years. However, if you’ve already noticed some damage or staining to your tiles, hire a grout repair specialist near you to repair and reseal the grout for a tile job that looks as good as new.