Drilling Plumbing Holes in Ceramic Tile

Tips on making neat holes in existing tile for pipe penetrations. November 26, 2007

I need to drill holes in a ceramic tile floor for water and drain lines under a bathroom sink. Any suggestions on drilling 1" and 1-1/2" holes in tile, or should I just remove a piece of tile, split it with a tile cutter, and then chip out the openings for the pipes?

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor M:
You could try a diamond hole saw. I believe the hardware store should sell them. No idea on price, though. Ceramic tile will cut better than porcelain tile.

From contributor R:
Try carbide grit hole saws. They are much cheaper than diamond and work great on tile.

From contributor E:
If your cutouts don't have to be perfect, lay out the cutouts on the tile and drill a series of small holes (3/16") around the outside of the lay-out lines with a small hammer drill and a sharp bit. Find the right piece of pipe hiding in the back of the truck, line it up with your circle, and ping it with a hammer.

From contributor D:
I'm assuming when you say under a sink, the holes are under a cabinet? If so, take the whole tile out, drill through subfloor, and you're done. If you leave the loose tiles under the cabinet and the homeowner ever wants to redo things, they have full tiles to cover the holes.

From the original questioner:
Thanks, everyone, for your suggestions!

From contributor S:
Bite the bullet and go for the diamond coring bits. Barring a major incident, they will last a long time. Carbide grit would be my next choice. I squirt a little water/Windex on the hole as I drill, depending on what I have on hand. Make a template or guide by drilling a hole in a 1x, locate it over the spot that you want, stand on your jig/template, and drill. Non-piloted hole saws have a bad habit of skating around, and the more critical the job, the more they skate.

If the hole is concealed, I like the idea of removing and saving the tile. I sometimes do this for base and other trim that might be useful down the road. For glazed ceramic tile and small holes, I prick the glazing with an awl to get a regular masonry bit to start easier.

Porcelain tile should have never been invented! Diamond cores cut it fairly well and for small holes, I tend to use the spade pointed glass bits. A glass installer turned me on to a three-sided solid carbide bit that worked pretty good, but I haven't acquired one yet.