Principal causes:
1. Absence of a horizontal waterproofing involves pulling up of capillary water. Salts being in it crystallize, destroying structure of materials by inflating the pores. Thus it becomes visible, as plaster pieces, fragments of a solution and bricks fall off.
2. Condensation of water steam acts in poorly ventilated premises, more often in bathrooms and basements. On surfaces of a ceiling and walls there are water drops. It is a condensate of water steam.
As a result we can observe dark wet stains. It is a sure sign of presence of hygroscopical salts in the wall. These salts don’t require liquid water for dissolution. The vapor is quite enough.
3. Water influence outside of the building.
— Snow sticking, hit of water splashes.
— Incorrectly executed biases.
Consequently the building becomes flooded.
— Damage or poor made roofing works and water waste elements.
Consequence - damage of drainpipes and a flood of buildings.
