What Is the Proper Spacing for Ceramic Tile?

Overall Recommendations

• Because most tiles vary slightly in their facial dimensions, the rule of thumb is: For every sixteenth of an inch in difference between two same-sized tiles, you should use a three-sixteenth-inch-wide grout joint, with another three sixteenths of an inch for every additional sixteenth of an inch in difference. The larger the joint, the more it hides size differences.

Mosaics

• Ceramic mosaics are usually manufactured and installed in a sheet format. The pre-determined joints are usually about an eighth of an inch, but you can spread the joints wider if required by an installation -- such as when a floor is just slightly out of square, and you need to make up a quarter of an inch in 10 feet. In this case, you can cut the sheet with a utility knife, and spread the tiles out a bit.

Lugged Wall Tile

• Four-inch wall tile is manufactured with lugs on the sides of the tile. These lugs are meant to butt up against the lugs on other tiles, forcing a spacing of at least a sixteenth of an inch between the tiles. This is where the term stacking tile comes from, as you normally start wall tiles on the bottom of the installation and stack them on top of and next to each other as you work your way up the wall.

Other Considerations

• Because there are no hard guidelines dictating the actual size of the grout joints in your installation, you can change them at will, depending on your preference. The overall idea is that the more uniform the tiles, the tighter the joint you can run, with the average grout joint somewhere between three sixteenths of an inch and a quarter inch. Anything larger than that is generally reserved for natural stone tiles with their considerable size variations.