What is the purpose of back buttering tiles?

Back buttering tiles involves applying a layer of thin-set mortar directly to the back of the tile before it is set onto the substrate. This practice serves a crucial purpose in ensuring proper adhesion and support for the tile. By back buttering, you enhance the contact area between the tile and the adhesive, which helps to prevent issues such as air pockets, which can lead to weak bonds, tile movement, or even breaking.

This technique is particularly important when working with larger format tiles, as they often require a more robust adherence method to ensure stability and prevent cracking. Additionally, back buttering contributes to achieving a uniform thickness of mortar under the tile, which is essential for a flat and level installation. This improved bond strength becomes crucial in conditions where tiles will face heavy foot traffic or varying temperature changes.

Filling spaces between tiles is a function of grout application, not back buttering. Creating decorative designs is unrelated to the structural integrity and adhesion provided by back buttering. Changing the tile's color is not a task that back buttering addresses; it's a matter that is determined by the tile itself and any potential surface treatments.