Rising Dampness / Kallar (Efflorescencer)
Efflorescence is the white, yellow, or brown chalky powder that you might find on the surface of a concrete or brick wall which is an indication of moisture intrusion that could lead to major structural and indoor air quality issues. This also compromises the strength of the structural material.
These are basically dissolved salts deposited on the surface of a porous material that is visible after the evaporation of the water in which it was transported.
Building materials, such as concrete, wood, brick, and stone, are porous materials. Porous materials can absorb or wick water by a process called capillary action. As water moves through the porous material, salts can be drawn with it.To re-establish equilibrium through osmosis, water rushes toward the salt deposit to dilute the concentration and creates massive hydrostatic pressures within the porous material.
The pressure from osmosis can create incredibly strong hydrostatic pressure i.e. 3,000 to 5,000 psi as compared to diffusion vapor pressure: 0.3 to 0.5 psi and capillary pressure: 300 to 500 psi.This high pressure created by osmosis is greater than the strength of the structure and can cause them to crack, flake or break apart.
We apply an impregnating hydrophobic sealant through various methods to a surface to prevent the intrusion of water which also prevents water from traveling to the surface from within.