What does the term "deflection" refer to in tile installations?

The term "deflection" in tile installations specifically refers to the extent to which a substrate bends or flexes under load. When tiles are installed, they rely on a stable and strong substrate to maintain their integrity. If the substrate's deflection is excessive, it can lead to cracks in the tiles, grout joint failure, or even complete tile installation failure. Therefore, understanding and controlling deflection is crucial for ensuring that the tile installation remains durable and visually appealing over time.

The other choices do not accurately define deflection. Moisture absorption by tiles relates to their permeability and ability to resist water damage but does not convey the concept of bending under load. Tile alignment is focused on how evenly the tiles are placed rather than their physical resilience under stress. The thickness of grout joints pertains to the spacing between tiles and does not involve substrate deformation. Each of these other aspects is important in tile installation, but they do not pertain to the specific term "deflection."