What is the purpose of grout in tile installation?

The purpose of grout in tile installation is primarily to fill the joints between tiles and prevent water penetration. This is essential not only for maintaining the integrity of the installation but also for enhancing the longevity of the tiled surface. Grout acts as a barrier that minimizes the chances of moisture seeping underneath the tiles, which can lead to mold growth and damage to the subfloor. Properly applied grout helps maintain a secure bond between the tiles, ensuring they remain in place and function as intended.

While grout can also slightly affect the aesthetic appearance of the installation by providing contrast or harmony with the tiles, its main function is practical and protective rather than purely decorative. Structural support is predominantly provided by the tile and substrate rather than the grout itself. Enhancing the color of the tiles is not a primary role of grout, as its intended purpose is to serve as a filler and barrier rather than a color enhancer. Therefore, the correct answer reflects the essential protective role that grout plays in tile installations.