Efflorescence and Spalling

Efflorescence refers to the deposit of water-soluble salts on the outside of painted masonry surfaces, such as stucco, concrete, volcanic-ash cinder block, and mortar between blocks. Water-soluble salts are leached out of the masonry when water penetrates the masomy from the inside. When water evaporates from the painted surface, it leaves a deposit of salts. Although the salts can be washed off with a stream of water, they will form again unless the source of water behind the paint is removed. Many times, the source is a leaking roof 

Spalling refers to masomy flaking off when the water in it freezes the paint, of course, comes off with the masomy. Spalling results from the same moisture sources as does efflorescence, and spalling can be corrected in the same ways as efflorescence. 

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