How To Cut Existing Ceramic Tile For Fan Switch Or New Electrical Outlet

While replacing electrical wiring during a recent whole-house remodel, a fan switch had to be installed in a tiled bathroom wall. There were no spare tiles, so great care had to be taken to not cause cracks or other damage. With the right tools and a steady hand, here’s how to accomplish that task without too much trouble.

• First make an outline of where you want to cut. Use a Sharpie or similar marker that will not smudge.
• Cover the top and bottom marks with masking tape as shown. Trace the lines still visible under the tape, so you can see the lines clearly when you cut.

The purpose of the masking tape is to help keep your drill bit in place. The glazed surface of tile is so slippery that the tip of a drill bit is very likely to wander off.

• Be sure to use a bit that is meant for drilling into tile. Carefully drill a hole in each corner of your outline. The reason for the holes is to prevent having to over-cut the outline beyond the surface that will be hidden by the cover plate.
• Using a 4″ grinder fitted with a diamond blade, start making cuts in the tile. Unless you are certain there are no ‘live’ electrical wires or plumbing pipes behind the tile, keep the cuts as shallow as possible. You can probably use much cheaper carborundum blades instead of diamond. Buy several, as these blades will wear down quickly.
• Keep a close eye on the depth of the cuts, and be prepared for lots of sparks and a glowing blade edge. If this is your first time, keep a fire extinguisher handy. If this is your 100th time, do the same. Be smart, not clever.

• It is to be expected that this procedure will generate a lot of dust. Wear goggles, ear protection, gloves and a mask. Open the window if you have one, turn on the fan, and, well, you get the idea. What you see in this photo are not cracks caused by our work, but rather crazing in the glazed surface, accentuated by dust from the diamond blade. With a narrow-tipped cold chisel or flat-blade screwdriver carefully chip away the tile inside the outline.

Unfortunately there is some framing that had to be chiseled away. I recommend drilling a series of holes with a new 1″ spade bit, and then chiseling out the remainder with a sharp chisel. Be gentle, try to avoid vibration as much as possible, and all will be well.

Any other ideas or tips? Please share!