Recently I had a water leak in the bathroom. I noticed water spilling out from the tiles grouting and I removed them to prevent any more water penetration.
I noticed that the following layers have been used:
carpet glue (or some kind of glue)
The underlay did a remarkable job of absorbing many liters of water but I cannot find what kind of underlay it is.
I am about to redo the work and I am asking around for advice. Some professionals strongly recomment AVOIDING the use of the underlay.
So.. My question is.. Should I use underlay? or should I simply glue the tiles on top of the plywood?