Tile grout is safe to paint as long as it is properly sealed. Paint should not be applied to unfinished or unsealed grout. To successfully paint tile grout, it is best to use paint specifically designed for grout instead of regular paint.
Before painting grout, it needs to be properly cleaned with tile cleaner to remove dirt and grime. Properly cleaning the grout before applying paint ensures that the paint adheres to the grout and does not peel off. It is best to apply grout paint with a small paint brush, such as a foam brush. Once the grout paint dries, it should be sealed with tile sealant to help protect the color and prevent stains.