How tiles are cut, and why the dust matters

Ceramic or porcelain: why it matters

Ceramic wall tiles have a softer, more porous body under the glaze, so they score and snap cleanly and drill easily. Porcelain is fired harder and denser. It is tougher to score, can snap off line if the wheel is worn, and needs diamond tools for holes. Large porcelain is heavy and can bow very slightly, which makes a long snap less predictable. Natural stone and glass each need their own blades. Knowing which tile is on the job tells you which tool comes out.

Manual cutter, wet saw or grinder

Manual cutter. A rail cutter with a scoring wheel and a breaker. Quick, quiet and nearly dust-free for straight cuts in ceramic and most porcelain. It cannot do notches or curves, and very thin strips tend to break.

Wet saw. A diamond blade cooled with water, on a sliding table or as a bridge saw. It cuts dense porcelain, stone and thick tiles cleanly and makes 45 degree mitres for outside corners. The water keeps the blade cool and the dust down.

Angle grinder with a diamond blade. For L-shaped cuts round door frames, notches, and trimming a tile already on the wall. It is fast, the dustiest of the three and the hardest to steer accurately, so it is used where the others cannot reach.

Nippers and a rubbing stone. For nibbling small curves in ceramic and mosaic, and smoothing cut edges.

Holes for pipes and sockets

Round holes are cut with a hole saw: tungsten carbide for soft ceramic, diamond core bits for porcelain and stone, kept wet or cool so they do not overheat. Many tilers start the bit at an angle so it does not skate on the glaze, then bring it square. A socket usually needs a notch across two tiles or a square cut in from an edge. Mark from where the pipes actually are, not from a drawing, because they are rarely exactly where they were meant to be. Some tile suppliers and stone workshops will cut large slabs, mitres or awkward shapes to order; ask when you buy.

Silica dust and why tilers cut outside

Tiles, stone and many adhesives contain crystalline silica. Cutting, grinding and drilling them makes fine dust that can be breathed deep into the lungs, and HSE treats respirable crystalline silica as a serious health risk with a workplace exposure limit. Its guidance for construction is to control dust at the source: water on the blade, on-tool extraction into a suitable vacuum, and a properly fitted mask as a backup rather than the only control. That is why tilers set up a wet saw outside or in a garage, and why a grinder used indoors should have a shroud and an extractor on it. Dry sweeping lifts the dust back into the air, so it is vacuumed up instead.

Common questions