Grouting Ceramic Tile - It is REALLY Easy!
So, you survived the grout removal ordeal. Do you want to take a break or can you run with the big dogs and just keep going? Great, I knew you could do it. Let's get the few tools we need and get right to it.
Tools - The Bare Minimum
Installing ceramic tile grout requires only one sophisticated tool and a good sponge. You need a hard rubber float that has a crisp edge. These floats can be found at virtually any tile specialty shop. Don't get a rubber float that looks like it has a sponge pad! I want a float that has smooth rubber.
The sponge is very important. Grout sponges are synthetic and have rounded edges, NO sharp 90 degree angles anywhere. I like to use a sponge that measures approximately 5 by 7 inches and is 1.5 inches thick. You will need two clean five gallon buckets and a three inch wide mixing knife of some sort.
Wall Grout and Sanded Grout
Wall grout generally doesn't have sand particles in it. Sanded grout contains fine grain silica sand. It is used to grout joints 1/8 inch and bigger. Standard wall tile in most bathrooms will not accept sanded grout. It is used for larger tiles such as 8 x 8 and up where the grout joint is often 3/8 inch or so.
Mixing the Grout
I like to use clean water. I have tried the fancy additives. However, if you use colored grout, you may have problems with color uniformity. Only mix enough grout that you can use in one hour or so. That translates to about 32 volumetric ounces for an average job. Remember, it only takes four to five minutes to mix a batch. If you go slower and the grout hardens, you have to throw it away.
Mix the grout by hand until it resembles the consistency of cake icing. It should be able to stick onto a knife without any trouble. I don't want it as thick as peanut butter. Think you can handle that? As you begin to mix, the grout will seem lumpy. Mix it for about two minutes and just let it sit for three minutes. Spend this time getting warm water into the other clean bucket. When you get back with the water you will notice that the lumps disappear with a little additional mixing.
Start High - Work Down
I want you to only grout about five to six square feet at a time. Use the mixing knife to apply a wad of grout to the tile. Then wet the rubber float. Using back and forth strokes, bulldoze the grout across the tile. Always cross over the grout joints between tiles at a 45 degree angle while holding the rubber float at a 45 degree angle. Grout will get all over the tile and it will look a mess! That's OK. The grout lines will look fat and messy at this time. Remove as much excess from the tile as possible with the rubber float. Pull the float across the tile at a 45 degree angle to remove the excess grout.
Striking the Joints
Now for the fun part! Take the sponge and immerse it in the water. Squeeze the sponge to remove ALL water. Then gently rub the sponge across the face of the tile in a circular motion. The sponge will quickly fill up with grout. Rinse it out and squeeze the sponge dry again. Do this over the area you grouted until the tile looks fairly clean. The joints will still look fairly rough.
Rinse the sponge again. Now, turn the sponge on its edge. Run the sponge lightly up and down a grout line. You will notice that you can control the amount of grout in a joint by the amount of pressure you apply. More pressure, less grout in the joint. I like my joints about 1/8 inch or slightly less. Do this process on all grout lines and it will look first class. Rinse the sponge frequently.
If you did everything correctly, the joints will look perfect. However, there is still a haze on the tile. Wait about one hour or so until the grout firms up, and you can remove the haze with a clean and practically dry sponge.
Water - The Enemy
You need water, lots of it, to do a grout job. But the water is also your worst enemy. If you have too much water in the sponge as you strike the joints, you can dissolve some of the cement out of the grout. This will make it weak. It will crumble over time and/or powder and dust. Just squeeze the sponge hard every time you rinse and you should be fine.
Also, don't grout between the tub and the first row of tile. This joint should be caulked. Grout will get into this joint as you do the rest. No problem. Just use a tooth pick to remove it as soon as you finish striking the joints above it. The soft grout will readily come out with the tooth pick. Let the new grout dry 24 hours before using the shower. Any grout haze on the tile will come off with a soft towel.