Cutting a hole in a piece of tile is one thing, it is a different proposition to cut a hole in tile that has already been laid. You have to be careful not to cause the tile to crack. It can be done. Here is what you will need:
- A RotoZip tool.
- A RotoZip diamond grit Floor Tile XBIT
- An electric drill
- A hole saw attachment for your drill.
- A magic marker or carpenter's crayon.
- A vacuum cleaner
- Aluminum Snap-Lock pipe
- Bathroom and kitchen caulking
- A caulking gun
- Tin snips
- SAFETY GOGGLES (No joke, you are going to put your face very close to high speed equipment and flying particles. DO NOT follow these instructions without proper eye protection or you will hurt yourself.)
- Dust mask. You are going to be hovering close to a dusty work area for an extended period of time.
Mark the hole.
Begin by marking the outline of your hole on the tile. You do not want your hole obstructed by floor joists, plumbing or wiring. Look under the floor before you begin and make sure you know what is underneath your hole. (Find a "landmark" such as a pipe, electrical outlet or heating vent from which you can measure distance below and above the floor to make sure you will not encounter obstacles.)
Depending on the color and surface of the tile, you will find a magic marker or a carpenter's crayon most effective. Simply trace the outline of the hole saw drill attachment in the desired location. After you cut through the tile, you will use the hole saw to cut through the sub floor, so it is okay if your circle is a little wider than the hole saw itself, in fact, you want that or else the hole saw will get stuck if it does not have a little play. An outline of the hole saw will be just the right diameter.
Cut the hole.
Put on your dust mask and safety goggles. With the diamond grit floor tile bit on the RotoZip tool, begin to cut your hole. START VERY GENTLY. The trick here is that you are going to slowly make many passes around the circumference of your hole, cutting an ever-deepening groove. Be very patient, it will take some time. Until you have an established groove, you risk having the tool "jump" on you and scratching the tile. To avoid this, start the tool above the tile and slowly lower it to the tile at about a 45 degree angle to make contact -- not straight down. You are not "drilling" -- think more like "engraving" or "routing." Slowly move the bit around the marked circle in a clockwise direction. Keep the bit at an angle to the floor. As you make several passes, you will begin to cut a circular groove. As the groove deepens, you will be able to speed up your progress by GENTLY "rocking" the bit from an angle to vertical and back again as you go around the circle.
Vacuum and cool
Dust in the groove you are cutting will slow your progress. A heated bit will slow your progress. Vacuum the dust from the groove often. Let the bit cool while you are vacuuming and maybe an additional couple of minutes of cooling every so often.
Finish cutting the tile and backerboard
Depending on how your floor was laid, you may find a layer of backerboard beneath your tile (you should hope so, actually, as that is part of a professional installation). Continue to cut with the RotoZip if you encounter backerboard. Cut completely through the tile, cement and backerboard. You should end up with a circular piece of tile and backerboard you can lift or gently pry out of your hole. (If the tile remains attached, just move to the next step. You can use the hole saw in the groove you have cut, just make sure you have cut a groove all the way to the wood.)
Finish cutting the hole
Once you have reached the wood sub floor, use your drill with the hole saw attached to complete the hole. Hold the drill vertically and "drill" straight down until you have sawed completely through the floor. Congratulations! You've made a hole!
Making a dryer vent.
If the purpose of your hole is to vent a dryer, use the tin snips to cut the aluminum snap-lock pipe to length. "Roll" it to lock it into shape. Friction may hold the pipe in your hole, or you can use some duct tape on the other side to hold it in place. Apply caulking. Let dry. You can now attach your dryer vent to this pipe and vent it from underneath your house as desired.
This is what you have when you finish: