What can be used to fill gaps in tile, particularly in corners?

Caulk is an ideal material for filling gaps in tile, especially in corners, due to its flexibility and ease of application. Unlike grout, which is primarily designed for filling joints between tiles and hardening to create a rigid bond, caulk remains pliable after curing. This flexibility is crucial in corners where movement may occur, such as in areas where walls meet or around fixtures.

Using caulk in these areas helps to absorb any minor shifts that might otherwise cause cracking or separation. Additionally, caulk typically has a smoother texture and can adhere better to non-porous surfaces, making it suitable for areas subject to moisture, like bathrooms or kitchens, where tiles are often used.

In contrast, while epoxy, grout, and silicone sealant have their specific uses, they may not provide the same level of flexibility or adhesion for corner applications. Epoxy is extremely durable but is geared more towards structural bonds. Grout is perfect for filling larger joints but can crack if used in areas subjected to movement. Silicone sealant shares properties with caulk in terms of flexibility and moisture resistance but is often used for specific applications like sealing glass or joining different materials, making caulk the more conventional choice for corner gaps in tiled surfaces.