Tile Installation: Grouting

Your tile is down. You’ve let the adhesive set up overnight and now, you are about to move to the final step of the project, applying the grout.

Grout is the substance that fills the gap between the tiles. Grout comes in two general types, sanded and unsanded.

Sanded grout includes fine sand in its composition. The sand helps to strengthen the grout and is used for large tile applications such as floors where the joints are at least 1/8 inch wide.

Unsanded grout can be used with smaller tiles to fill narrow joints less than 1/8 inch.

If your tile is ceramic or a stone such polish marble, it is best to use an unsanded grout. This won’t scratch the finish on the tile.

When it comes to grout color, there is a wide selection. Some grout colors will blend with your tile, while some will contrast with the tile color calling attention to the overall pattern. Either way, be sure to pick up some sample sticks from the tile shop to figure out which one is right for you.

Before you start grouting, wipe any excess adhesive off your tile and out of the grout joints. Extra adhesive will prevent the grout from filling in the joints properly. It’s also important to know that certain stone tiles such as slate and marble need to be sealed before grouting. This will prevent them from becoming discolored by the grout.

To mix the grout, you will need a bucket, some clean water and the grout mix. And always read the manufacturers instructions to see if you’ll need any other extra additives. Start mixing the grout by pouring a little clean water in a bucket then add in your grout and stir together. You can then add a little more grout or water as needed. Your goal is the consistency of toothpaste. Be careful not to go crazy stirring it all together. Overmixing will create air bubbles that can weaken the grout’s integrity.

Once the grout is mixed, allow it to sit for 10 to 15 minutes before applying it. This is called slaking and it lets the pigments and chemicals in the grout integrate completely.

Spreading the grout works best with a good rubber float. Hold the float at a 45 degree angle and sweep the grout over the tile and into the joints as you work one reachable section at a time. Work the float back and fort in a direction diagonal to the tile pattern. This may take a few passes until every joint is completely filled.

If you’re grouting tiles with an embossed surface, the float will not be able to press the grout deep enough, if that’s the case, just use your fingers instead. Spread the grout over each seam pressing it in firmly. Your grout will tend to stiffen up as it sits in your bucket, so stir it regularly to keep it lose. After a several passes with you fingers or trowel, the tile will have slight haze on the surface. You can remove this haze with a damp sponge. Let it sit for an hour and give the tile a polish with a soft clean cloth.

That’s it. Your grouting is complete. Now, just sit back and admire you work.