How to Grout Like a Pro!

gloved hand using grouting tool

Grout doesn’t get the same attention that tile does, but it’s just as important when it comes to the finished product. While it may seem like a simple thing to pick out, there are some important things to know before tackling this job.

Whether you’re doing a simple backsplash or your entire bathroom, here’s how to grout like a pro!

Choose Your Color Wisely

With so much focus on tile design, grout color can be an afterthought. Don’t wait until after the tiles have been laid and you’re at the hardware store, choose grout color at the same time you pick out your tile.

It might seem like there are only a few choices, but there are about thirty different grout colors available. So, if you were thinking of going with “just white,” know that there’s “bright white,” “antique white,” “snow white,” “bone,” “linen,” “avalanche,” etcetera.

In terms of how to choose the color, lighter grout colors are the most popular and go well with many colors and styles of tile. However, if you’ve laid down darker tiles, you may want to choose a grout shade that’s closer to them. Black tiles look stunning with dark grays like charcoal or pewter, for example.

It’s not as common to use a dark grout color with a lighter tile, but it’s not unheard of. White subway tiles with charcoal grout lines look stunning, and dark grout can accent deep blues and greens nicely.

There are other considerations besides style to consider. Dark grout is more forgiving on floors with a lot of foot traffic, whereas white grout will need constant cleaning. Keep in mind that dark grout will take more care and cleaning when first applying.

It really just depends on the look you are going for, and whether you want your tiles to blend in or have more of a contrast.

hand scraping grout

Choose The Right Kind

Thankfully there aren’t that many choices when it comes to the kind of grout you want to use, except for whether to go with sanded or un-sanded for most standard tiles.

Sanded grout is a lot stronger and grittier than un-sanded because of the added aggregate material. It’s better at holding its structure and won’t shrink as much as un-sanded grout does.

Sanded grout is recommended for use on floors, and anywhere you are using wider grout lines from 1/4th to one inch, (though grout lines shouldn’t be wider than an inch in normal applications).

Un-sanded grout is smooth and best used for wall tile applications or any tighter joint lines, from 1/16th to 1/8th or smaller. When un-sanded grout dries, it will shrink a bit, and possibly pull away from tiles if not filled in properly.

It may also crack when any kind of weight is placed against it, again making it generally unsuitable for floor projects, but perfect for holding a nice shape on walls and backsplashes.

Grout For Different Tiles

The majority of tiles that you find at big box stores can be used with either the sanded or un-sanded grout. However, some specialty tiles, like marble, granite, or limestone, will need some more thought.

These soft tiles can easily be scratched by sanded grout, so un-sanded is recommended. However, there are also specialty grout materials for certain situations.

An epoxy or acrylic grout may be necessary when laying marble floors since sanded grout will scratch them, and un-sanded doesn’t hold up as floor grout. These specialty grouts may also be recommended for marble wall tiles, as marble is quite heavy.

Epoxy grout has an extremely strong bond and is also resistant to stains and chemicals. It can be great for industrial applications and commercial kitchens or for large bathrooms made of only marble, for example. Just note that it’s a very tricky product to work with, and not always recommended for DIY jobs, as it dries quickly, and can be hard to spread.

Acrylic grout contains a certain amount of silicone and cement and is great for outdoor tiles on a patio or in a garage, for instance. It’s stain-resistant, can withstand extreme temperatures, and resists moisture far better than any other grout types.

Acrylic may also be recommended for soft tiles like marble and granite as it has a strong bond without scratching the surface, and is much easier to work with than epoxy.

Keep in mind that epoxy and acrylic grouts are expensive, and will be either special order items or need to be sourced at specialty tile stores. If you are purchasing a specialty type of tile, the salesperson should know what kind of grout you need.

hand scraping grout with plastic tool

Get the Right Tools

Once you’ve picked out your grout, you need the right tools to get the job done like a pro. There isn’t a lot needed, but it’s important to have the proper arsenal.

A grout float is the only tool you should use to apply un-sanded or sanded grout. It’s a handheld rectangular tool that has a soft face so that you don’t scratch the tile when you apply it. The shape and weight of it mean you can apply it easily with one hand for a fast and easy application.

Sponge(s) are essential for cleaning the tiles. Again, you want something that is soft but sturdy enough to clean the surface of excess grout without harming it. While you can get away with just one, it’s easier with two or three, especially for wiping away darker colors. Use one for the first few wipes, and another one as your “clean” sponge for the final wipes.

The best way to mix your grout is to have a strong drill and mixer attachment. Most hand drills are strong enough to handle the job, but because of the viscosity of grout, it takes a lot of power to mix the materials, and this can kill the motor on some drills. Corded drills are usually stronger and can draw enough consistent energy to mix larger batches of thick grout.

Buckets are very important as you’ll need one to mix the grout in, and one for clean water. Large paint pails work the best, but anything that is clean and large enough to hold the grout will do. You can’t mix up grout properly in a small bucket, it will move around, and the mixture will fly out when it’s being mixed. Handles will also be helpful.

How to Mix Properly

The best way to get the perfect grout slurry is to follow the directions on the bag. Some contractors like to do it based on feel, which is also okay as look as you are careful.

Start by adding a small amount of grout powder into the bucket. Add a little bit of water and gently use your grout float to mix it around and get the feel of it. The ideal texture is going to be heavy enough so that it isn’t runny, but soft enough that it can be applied.

Because of the grittiness, sanded grout will have a thick milkshake consistency. You want it so that if you turned the cup upside down, it would fall out slowly. Un-sanded will be silky like smooth peanut butter, but also malleable enough to spread it without being wet or drippy.

As you get the consistency right, add more powder and water to get the amount you need. If you aren’t good at eyeballing how much you should use, stick to the instructions on the bag.

When mixing, make sure to get everything at the bottom and on the sides. You don’t want any “stragglers” or powder that hasn’t been mixed in thoroughly enough.

Mix in stages so that you don’t have too much to handle at once. After you have thoroughly mixed it, let it stand for about ten minutes, then mix it one more time. Now you’re ready to apply it.

mixing grout

How to Apply

Take your bucket of grout and your float and start at one end of the tile working your way across. If working on a large area like an entire bathroom, do it in sections. For floors, make sure you don’t corner yourself.

Depending on the size of the tiles, you may only apply grout directly into the lines if they are large, or for smaller tiles, it will be easier to spread the grout across the whole surface and not worry about just hitting the lines.

Either way, make sure you get enough grout into the lines so that it goes in deep, using the longer edge of the float to wipe across them a few times: up, down, and side-to-side. Try not to leave too much excess grout on the tile, though there will be some, and that’s completely fine.

The grout residue will turn hazy as you go about the job, but you have time to clean the surface before it sets. For normal sized applications from backsplashes to kitchen floors, you should be able to get all the lines filled before you need to worry about the grout drying.

If you think that the grout has started to dry, do a quick wipe with a wet sponge over the tile surface to keep it from permanently setting. You have about twenty to thirty minutes before it will start to set up.

How to Wipe the Tiles

Once the grout has been applied, you can do your first wipe about ten to fifteen minutes after it’s all done. For regular applications, by the time you’ve finished applying the grout, you may be ready to start wiping the other side where you started.

Dip your sponge in clean water, and squeeze it so that it’s wet, but not sopping. Gently wipe the tile surface, not focusing on the grout lines themselves just yet. You want to remove the haze that has formed on the tiles first.

When the sponge gets dirty, douse it in the water to clean most of it off and continue the task. It’s okay to use the same bucket of water for this step. You want to get as much of the residue off as possible, but not so aggressively that you disturb the lines.

Do a couple of wipes and fill in any spots as needed with extra grout that you should still have around (don’t throw it out right away). Then wait another ten minutes or so before you clean the grout lines.

How to Clean Grout Lines

With a clean sponge and fresh water, start wiping the grout lines themselves to get them nice and even. This should be done with a soft touch so that you aren’t moving any grout around—you want to graze along the surface so that excess grout material is taken away, and the grout sits nicely just inside the tile edge.

A clean, wet sponge will be ideal for this, so wash it frequently as you go, keeping it moist enough so that it creates nice smooth wipes.

Once you’ve cleaned all the grout lines, and there is no residue on the tiles, let them sit for another ten minutes before doing a final wipe.

Final Touches

Your final wipe should be done with a clean sponge and fresh water, as you want to make sure that nothing is left on the surface of the tile. If any grout is left over, it will dry and stick to the tile permanently.

You may not need to wipe every line at this time, but go over the entire space to make sure you are happy with the final look. This is also the last call for adding any extra grout to lines that may have shrunk or been wiped away during the cleaning and drying process.

These little bubbles or empty spaces are called “pinholes” and need to be filled, not only because they look shoddy but also to keep water out. Keep your grout around until the end for this reason.

When the grout lines are all firmly in place and ready for drying, you can do one final clean wipe of the surface to ensure there won’t be any grout scum left on the tile.

For the best results, don't rush any of these processes. Just as laying tile requires discipline and patience, grouting requires you to pay attention to detail. While it isn't necessarily a difficult thing to master, timing is important, and a certain amount of elbow grease is required.

Give grout the proper attention it deserves, and you'll come away with a project that you're proud of. By following these steps, you'll be grouting like a pro in no time.