Quick Answer

For a faucet hole in porcelain tile, use a 35mm diamond core bit (or 32-38mm for standard faucets) with water cooling, or a dry diamond bit run slow in short intervals. Start on masking tape, drill at low speed with light pressure, and keep the glaze from chipping by letting the diamond edge cut through before increasing speed.

Common Hole Sizes in Tile and Stone

Application	Recommended Core Bit
Faucet / tap hole	35mm (32-38mm)
Shower arm	22mm
Soap dispenser	32mm
Waste / drain through stone	45-60mm

How to Drill Tile Without Cracking

• Stick masking tape over the hole centre to stop the crown skating.
• Use a pilot or guide plate for holes over 25mm.
• Start at low speed (handheld, 300-500 RPM) with very light pressure.
• Wet drilling: keep a small water pool on the tape — the slurry lubricates.
• Dry drilling: 10-15 seconds on, cool, repeat until through the glaze.
• Once through the tile, slow down when you reach the substrate to avoid chip-out.

Wet or Dry for Tile and Stone?

• Wet — granite, marble, engineered stone; best finish, longer life.
• Dry — porcelain, ceramic and tile on walls where water is messy; use interval drilling with our diamond core bits.

Safety Tips

• Wear eye protection — tile shards are sharp.
• Do not apply sideways pressure; it snaps the crown.
• Check the tile is fully supported behind the hole point.

Frequently Asked Questions

Q: Will a masonry bit work on porcelain tile?

A: Poorly — porcelain needs a diamond core bit. A standard masonry bit heats and slides on the glaze. Use our stone hole saws for clean results.

Q: Why does my tile chip on the back side?

A:Breakthrough chip-out — reduce feed as you exit and keep the bit square. Backing board support also helps.

Q: Can I drill a faucet hole in a countertop after installation?

A: Yes, carefully, with the sink protected. Cover the area with tape, keep the drill square and go slowly.

Conclusion

Size the bit to the fixture, tape and pilot for a centred start, and drill slowly through the glaze — that keeps tile and stone holes chip-free. JOY TECH supplies diamond tile bits and stone hole saws in single and bulk packs; contact us for pricing.