QUESTIONHydrostatic Pressure causing tile to Debond? - you mention hydrostatic pressure can make tile tent--how do you resolve that problem?
ANSWERANSWER - In theory hydrostatic pressure can cause a tile to debond if the hydrostatic pressure is greater than the tensile strength of the adhesive bonding the tile to the substrate. If a tile is poorly bonded it takes less force to cause it to debond or tent. So the question is whether the tile is poorly bonded or is the hydrostatic pressure that great?
Often people misunderstand the definition of or the condition of hydrostatic pressure and wrongly associate it to a moisture problem. Hydrostatic pressure in effect is where the water table is higher than the point where the water is being forced up from. Sometimes this could be a significant pressure and sometimes not.
The answer to the question of how to remediate a hydrostatic problem is it depends on what the condition is and what is the source of the hydrostatic condition.
Using vapor retarders under slabs and constructing French perimeter drains to control the flow of the water can work in some cases, but it depends on what are the conditions.