No 3. Loose and Drummy Tiles
During every Abis Pre-Purchase Inspection all accessible wall and floor tiling is sounded by trapping with a special tool (A shaft with a non-marking ball on the end) to detect loose and drummy tiles. The inspector is listening to the frequency of the sound produced. Where there is an air space under the tile the sound has a lower pitch and is referred to as "Drummy"
So why is this an issue?
Drummy or hollow sounding tiles indicate an air space under the tile that is indicative of one or more of the following problems.
- The adhesive not having a good bond between the tiles and the substrate.
- There being "voids" of missing adhesive under the tiles.
Tiles which sound drummy are no longer adhered properly and may dislodge. In the case of floors subjected to foot traffic, the tiles that are not correctly laid will most likely break, crack, chip or fail in some other way. In extreme circumstances, the tiles will actually lift off the floor.
This is usually due to old adhesives, incorrect tiling, poor preparation before tiling (removing dirt or paint) or tiles laid too close together with no control joints to allow for expansion.
Another common cause of drummy tiles is the use of tiles with a different coefficient of expansion to the substrate to which they are attached, such as a concrete slab floor. The installation of control joins and the use of flexible tile adhesive can minimise this problem.
Where a drummy tiles are reported the client should seek advice from a licenced tiler to the establish the extent of remedial work required and associated costs. This is particularly important where the drumminess is widespread.