Grout is the material that fills the joints between tiles. Grout can be water-resistant. However, water or other liquids, will most likely penetrate the joint and reach the backing. The best thing is to ALWAYS seal your grout and it is a maintenance issue to be done every 2 to 3 years. There are two major classifications of grout: Portland Cement Grout and Epoxy Grout.
Of these two, there are two basic types: sanded or non-sanded. Sanded grouts should be used when grout joints are 1/8″ or larger. Non-sanded grouts should be used in a joint 1/8″ or smaller. Sanded grouts-grout joints 1/8″ or larger and Non-Sanded grouts-grout joints 1/8″ or smaller.
