The size of the grout joint can dramatically change the way your overall tile installation looks. It is important to use the right size grout line for technical reasons and also for aesthetic reasons. For example, if you are using a marble or natural stone tile and the grout joint is too large, it can make the marble look fake. Natural stone is cut with such precision that the typical rule for natural stone is to set the tiles with a 1/16″ grout line. When each tile is more uniform, you have the luxury of using a smaller grout line. When tiles are fired in a kiln, there is no guarantee of the precision and uniformity of the edges.
Often, the size of the grout line is left up to the interior designer or the tile contractor. With their experience, they generally know the appropriate size grout joint for each different tile. Larger grout lines are needed for tiles with less than perfect edges so sometimes you can ask for a certain size grout joint, but your tile contractor may recommend that it be a little larger for a more professional looking installation.
There is no right or wrong answer for what size your grout line should be, but below are some guidelines:
- Natural stone – 1/16″ or 1/8″
- Tile with a rectified edge – 1/16″ or 1/8″
- Regular tile – 3/16″, 1/4″ (safest bet) up to 3/8″ or 1/2″
- Saltillo or Mexican tile – 3/4″, 1″, 1 1/4″
Also, it is important to know that there are two different types of grout: sanded and unsanded. Sanded grout is used in joints that are 1/8″ or larger and unsanded grout (natural stone and glass mosaics) is used in joints that are 1/8″ or larger. Salitillo or Mexican tile has its own type of grout.
For advice on how to choose a grout color, click here.