What is effloresence?
Efflorescence is a white crystalline or powdery deposit on the surface of cementitious masonry materials like concrete, brick, clay tile, etc. It's caused by water seeping through the pores in the cementitious material. The water dissolves free alkali and lime salts inside the material while migrating through it, then evaporates leaving the alkali deposited on the surface.
What is saponification?
Saponification is the chemical process of manufacturing soap. When soap is manufactured, the basic ingredients are forms of alkali and oil. The combination of the alkali in the masonry and the oil in the paint causes the saponification, which is the white soapy film which appears on the walls and floors. This also causes flaking, blistering, bleeding and burning off the paint on the surface. Vinyl, rubber or latex based paints also contain some oils and will peel and crack off masonry surfaces.
