STONE FACADE CARE
Water can cause more serious damages than a simple stain or water mark to the stones. In fact, water infiltration is one of the major factors that unleash the decay process for building materials. Just think to the damages that frost/defrosting can cause: when in low temperature the water penetrates in the stone pores and subsequently becomes ice thus increasing its volume/ As a result, the stone will be subjected to a very strong pressure from the inside. This pressure ca literally crumble the stone. A lesser known phenomenon but similar to the above described scenario is the infiltration in building materials of salts dissolved in water (for example the solphate coming from acid rains, the sodium chloride used to melt ice on the roads, the various salts present in adhesives, screeds or cements when used incorrectly.
These salts, in certain humid conditions and temperature, when transported into the stone by water, can crystallize and increase their own volume. This will cause great pressure inside the material, that can lead to very serious problems within a short time. Besides, the salts being hygroscopic attracts more humidity; when we say that a floor or a wall are "humid", in most cases it is due by the salts and sometime these salts are also visible in form of white sediment (efflorescence).
Stone facades are always effected by freeze and thaw cycles, that‘s why they need certain protection. The ability of stone to resist freeze and thaw cycles and constant humidity effect can be greatly increased (up to 10 times) with the help of protectives.
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