Diamond hole saws are the correct tool for cutting holes in ceramic tiles, porcelain, natural stone and glass — materials that standard bi-metal hole saws cannot handle without cracking. The diamond-coated edge cuts by abrasion rather than by teeth, which is why water cooling is essential: it keeps the cutting edge cool, prevents dust and extends tool life significantly. Position the hole saw carefully before starting — use a guide or start at low speed to establish the cut line before increasing speed. For wall tiles already in situ, always drill from the face, not the back. The JCB DiamondTech range covers the diameters most commonly needed for electrical back boxes, pipe penetrations and drainage outlets in tiling work.