Though grouting is the last step in creating a tile surface, it’s the one that’s most important to the overall appearance of the project and its durability. Improperly applied grout not only looks bad but also allows moisture to penetrate, which can cause tiles to loosen and even pop off. Fortunately, applying grout is a simple process; just follow these steps and you’ll be a success:
Mix the Grout (Photo 1)
Combine the powdered grout and water as specified on the grout packaging and let the mixture sit for about 10 minutes. This process, called slaking, allows the dry power to absorb all of the water. After the slaking period, the mixture should be similar to the consistency of mayonnaise. If it’s not, add a little more powder or water as needed, and let it slake again.
Spread the Grout (Photo 2)
Hold the grout float at a 45-degree angle to the tile surface and spread the grout into the crevices between the tiles. Make several passes from different directions. Once the joints have been filled, hold the float at a 90-degree angle to the tiled surface and remove any excess grout from the face of the tiles. Work quickly in areas no larger than 3 sq. ft., as grout can harden quickly depending on temperature and humidity levels.
Tool the Joints (Photo 3)
Drag the rounded corner of the grout float along every joint to create a concave appearance. If you prefer, you can use just about any small rounded object to tool the grout lines; however, don’t use anything metal, as metal edges may damage the tile.
Wipe off Excess (Photo 4)
Use a grout sponge and a big bucket of clean water to remove the excess grout from the tile. Wet the sponge and wring it out; then position the long edge of the sponge against the tile and drag it in one continuous stroke across the grouted area. Flip the sponge over and use the opposite clean edge to make another swipe; then rinse the sponge, wring it out and continue the process. You’ll probably need to make two or three passes to effectively clean one area. If a thin film of grout remains, don’t worry — it’s easily buffed out with a soft cloth.
Caulk the Edges (Photo 5)
Use a utility knife to remove the grout from the corners; then apply a flexible color-matched caulk that will allow for slight movement in these joints.
Seal the Grout (Photo 6)
Finally, apply a sealer to the grout to prevent it from staining. A rolling applicator that applies the sealer only to the grout makes fast work of this process — if you use a rag or sponge, you’ll need to buff the sealer off of the tile after it dries.