Ceramic tile can be finished is several ways. If you are, for example, you are installing ceramic tile for a shower surround, you typically have the option of using bullnose, or round over tiles at the perimeter. This gives a nice finished look along the perimeter of the tile. If you are using a tile that doesn’t have that finished option, you will have to create your own finished look with grout.
When you have unfinished tiles along an edge, they can be unsightly. By using grout, you can create a line from the top edge of the tile, down to the surface of the wall at a 45-degree angle.
Measure the distance from the wall’s surface to the top edge of the tile. Take that distance and make a mark from the tile edge along the wall’s surface. Run a piece of painter’s tape at this distance along the perimeter of the tile’s edge so that the tape runs parallel to the tile. You will be left with a gap from the tile to the tape.
Mix up some grout and push it into the space next to the tiles vertical edge. Use a float and, holding it at a 45-degree angle, push the grout into the triangular space to create the edge. Wait until the grout starts to set up and then slowly pull the tape in one continuous piece. You will be left with a perfect grout line that covers the unfinished tile edge.
At some point, you will have grout lines in your floor that need to be repaired. You will notice voids in the grout. More commonly, you will see cracks in between the grout and the wood baseboards. This may be due to seasonal movement or impact damage.
Grout can be sloppy to install. So the trick is to minimize getting grout where you don’t want it to go. Where the baseboard meets the tile, you can minimize this mess by using wide painters tape. Before you start taping, remove any loose grout and vacuum out the area.
Place the roll of tape flat on the floor and tape along the baseboard. This will make it so that the finished grout line is at the same level as the floor. I also tape along the edge of the tile so that the new grout won’t get on the old grout and tile. It’s okay if this happens, but they you will have two colors if the color of the new grout doesn’t perfectly match the color of the old grout.
So when you are done taping, you will have two pieces of tape with a small gap in between them. Now it’s time to start grouting. Use a grout float and fill the gap in between the tape. Use the corner of the float and push the grout into the gap. Try to remove as much of the grout as possible leaving a near finished surface.
Wait until the grout starts to dry on the tape. It will look much lighter than the grout in the gap. Gently pull the tape and it will leave a perfect grout line level with the floor. At this point you may choose to leave it alone or use a damp sponge to wipe the surface of the grout line.
Grout is everywhere and grout cracks are pretty common. I see a lot of people (homeowners and their handyman) cover grout cracks with caulking. Well, I guess that will stop water intrusion, but it won't look very good. Caulking doesn't have the same appearance as grout, and it likely won't match the color either. The best way to solve this problem is to replace the grout in that area.
Replacing the grout involves digging out the old grout, filling in the grout lines, and finally cleaning the area.
You have a couple of choices when removing the old grout. You can manually remove it or use a motorized tool. If you choose to manually remove it, use either a grout saw or a tool called a "grout grabber". They both work in the same manner which is placing the tool against the grout and running the tool against the grout while applying pressure. This almost guarantees blisters.
Your other choice is to use a Dremel-type tool. This is a fast spinning tool that spins a bit. The grout removing bit is placed against the grout and it turns it to dust. The only caution here is to have a steady hand as the bit will tend to break if you hit the surrounding tiles.
Once the old grout is removed, mix up a batch of grout, let it rest, and then use a float to stuff the grout into the voids. Use the float to remove the excess grout, let it dry to a haze (about 15 minutes), then buff with a clean white rag.