All About Tile Grout

Natural Grey Grout
The filler between tile joints is not an adhesive, but rather a concrete material called grout. A grey mortar is the typical color that has been traditionally used since Roman times. Grey grout allows you to focus on the color of your tile. It recedes from view. If you choose a colored grout for your project, it should be a very intentional decision as it often draws the eye as much as the color of the tiles does.
Grout Widths and Types of Grout
Joints 1/8" and larger require Sanded Grout. This includes most handmade tile. (Sanded Grout will not scratch the glazed surface of your tile.) Joints less than 1/8" most commonly use Unsanded Grout. This includes most commercial tile. Epoxy comes with added polymer chemicals and is the strongest of the grouts. It is sold both sanded and unsanded.
SANDED
For joints 1/8" and larger. Best with most handmade tile. (Sanded grout will not scratch the glazed surface of your tile.)
UNSANDED
For joints less than 1/8". Best with most commercial tile.
EPOXY
The strongest of grouts, it comes sanded or unsanded with added polymer chemicals.
How to Apply Grout

Mask
Apply masking tape to the face of dimensional or matte tiles before grouting speeds clean up and prevents grout from adhering to unglazed areas. Remove tape once grout has been cleaned.
Fill Joints
Wear rubber gloves. Force grout diagonally into joints with a rubber grout float or gloved hand. Ensure joints are completely filled. Wipe clean with a dry paper towel until haze is entirely gone. Do not use water.
Cure Grout 24 Hours
Allow grout to cure 24 hours before using tiled surface or applying an optional sealer.