Mineral building materials suffer extreme stress from the freeze-thaw cycles. The constant change in temperature around the freezing point means that the water keeps changing its physical condition constantly from liquid to solid. In these changes the water expands by around 9 vol.% and has an explosive effect based on the pressure of the ice.

Cracks in the coverings of balconies and terraces are much more than purely a visual flaw. They mean that rain, snow, and therefore water, have the chance to penetrate deep into the substrate. The damages that result from this may, in the worst case scenario, mean that the entire covering will need to be renewed. Water is able to penetrate these coverings through such cracks and can cause a lot of damage.

During curing cements split off water-soluble calcium salts.

Water present in the balcony and terrace system, maybe because the grouting on the edges of the joints has worn away or because there are small cavities under the tiles, is transported to the surface of the covering via vapour diffusion and capillary action, where it then evaporates. In the process calcium salts are deposited on the surface of the covering. Such deposits can frequently only be removed mechanically and lead to the discolouration of the tiles and natural stone

Vapour diffusion is another word for damp air that permeates through a building structure. As a matter of principle this vapour moves from the warm to the cold side of a building part. As soon as the water vapour reaches the cold spots, a condensate develops that collects below the cover’s surface. Strong sunlight now causes the vaporization of the condensate and a pressure develops that cannot escape via the cover’s joints.