Suggested Size for Tile Grout

4-inch Wall Tile

• Four-inch wall tiles are manufactured with what is known as lugs on the side of each piece. These lugs are small ridges of material that, when pressed, against an adjacent piece form a roughly 1/16-inch grout joint between the tiles. This allows for what is known as tile stacking, where you stack the tiles against each other during the installation. While you can make the joint bigger if you so choose, it is designed to be small.

Mosiac Sheets

• Small tiles, known as mosaics (1-inch and 2-inch pieces), are manufactured in 1-foot by 2-foot sheets where the joints are already pre-determined. For the most part, square mosaics have a 1/8-inch grout joint between them, although natural stone mosaics have random joint widths. You can widen the joints by cutting the rubber matting with a utility knife if you need to.

12-inch Tile

• The standard recommendation is 3/16-inch joints for every 1/16-inch variation in the size between tiles of a batch. For 12-inch tiles, this is usually the norm. Joints for standard 12-inch tiles usually range between 3/16-inch and 1/4-inch. While you can go larger if you choose, 1/4-inch is sufficient to hide the inconsistencies in size between tiles and create a good visual look for the installation.

Tumbled Natural Stone

• Grout joint width for tumbled natural stone installation varies on the stone, but for the most part these joints are usually 1/4-inch to 3/8-inch minimum. Flagstone installations can range upwards of 1/2-inch wide joints. This is because natural stone tiles, like tumbled marble, are not uniform in size and the difference between the stones is hidden with wider grout joints.