Installation of Tile
One of the keys to installation is making sure the surface on which the tile is applied is level and ready for installation. An adhesive, such as thin-set or mastic is then applied to the substrate with a trowel and the tile is laid on it. After the area dries, the tile is then grouted. Some tiles can benefit from being sealed before grouting to prevent grout film from adhering to the tile.
Although opinions are varied in the industry about sealing ceramic tile, ANN SACKS recommends that a sealer be used on all tile installations. It is strongly recommended that a small sample of a tile be tested with the sealer before an entire installation is sealed. Installations of crackle glazes should be resealed after 90 days of installation, and then again after one year. Crackle glazes (by nature) continue to crackle for several months. As this occurs, each new crackle line becomes unsealed and will allow water into the tile body.