Tile absorption should be tested before tiling in order to choose the right adhesive. An easy way to test tiles absorption is to drop little amount of water on the tile back. If water is absorbed quite quickly, the tile is considered to be normal absorbent type. If water is still on tile back and takes time to be absorbed, the tile is considered to be low-absorbent type. If water is always on tile back without any absorption, the tile is considered to be non-absorbent type.
Tiles can be differentiated according to their water absorption into 3 types as follow: