What is the purpose of caulk in tile installations?

The purpose of caulk in tile installations is primarily to fill gaps and provide flexibility in areas where tiles meet walls or other surfaces. This is crucial because tiles can expand and contract with changes in temperature and humidity. Caulk allows for this movement without cracking or damaging the grout lines between tiles.

Using caulk in the joints where tile edges meet wall surfaces or where different materials come together prevents water infiltration and helps reduce the risk of mold and mildew, which could otherwise be encouraged in these vulnerable joints. Caulk also maintains a clean and finished look around edges, ensuring a professional and aesthetically pleasing appearance in the tiled area.

While adhering tiles to the substrate is an important aspect of installation, this function is accomplished primarily using thin-set mortar or adhesive rather than caulk. Similarly, while a waterproof seal is essential, it is typically achieved with grout or specialized waterproof membranes, not caulk, and enhancing the tile's color is not a function of caulk but rather a characteristic of the tile material itself or a finish applied to the tile.