Hollow Tile Wall
If the entire tile floor sounds hollow then it is likely because of the underlying conditions.
Hollow tile wall. These types of anchors also expand as the screw is tightened and driven into the cavity. On the contrary over concrete if there is no deflection in the floor. Structural clay tile describes a category of burned clay building materials used to construct roofing walls and flooring for structural and non structural purposes especially in fireproofing applications. A tile floor over a wood subfloor will sound more like a hollow sound compared to a tile floor installed directly to a concrete slab.
If the tile is installed over a non bonded mortar bed it will sound more hollow than tile installed over a bonded. Hollow wall anchors are used for medium duty applications. Also called building tile structural terra cotta hollow tile and clay block the material is an extruded clay shape with substantial depth that allows it to be laid in the same manner. Grout and gravity will help keep the floor in place as long as there are sufficient movement joints in the tile and minimal shear forces.
While a tile floor with hollow spots is not ideal it does not necessarily mean that floor failure is imminent. They ll normally add permanent screw threads to any material to which they re attached.