[Huligar]

Cheesedog, the simple answer is yes.
The conditions that you just describe will cause condensation. The water can tan be absorbed by the wood and in time can cause mold and warping in the wood which than buckle under the weight of the 3 cm slab a cause for the breaking of your seams. The best way to stop this, is to seal your wood correctly and not to use that cheap wood like stuff you get from the big box stores. The stone is not the problem, the problem is what you but the stone on. So the best advice you could ever give some one, is to plan for the results you are looking for.