1) We have the walls of our stone SDB, and we would like to make the joints between the stones and then apply a white paint on the whole surface of the stone wall jointed. This wall will be exposed to splashing water ie about 4 showers a day. I would like to know which joint and which paint to apply knowing that all this must withstand moisture, condensation, heat,... 2) For this SDB, we have a floor (30mm thick) to lay on beams spaced every 30cm, we would like to shower in the Italian, knowing that we have access also from below the floor (there is a room). What can I ask on my beams (25cm thick ) to make my shower tray Italian?
For grouting stones, use a waterproof joint mortar. The stone is difficult to paint because, generally, its irregularity and its many crevices. You can of course try a "special bathroom" acrylic paint, preferably applied to the low pressure pistol...
The creation of a walk-in shower is really not recommended in your case. The wooden floor would not resist the slightest leak. The installation of a shower enclosure or a raised receiver isolated from the ground would be more suitable.
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