Efflorescence

Efflorescence is a crystalline deposit that forms on the surface of masonry, concrete, or stucco. It is caused by the migration of soluble salts to the surface of the material, where they then react with the air to form a white, powdery substance. Efflorescence can be unsightly, and may also be an indication of more serious problems, such as water damage or a problem with the material’s structural integrity.

In exterior cleaning, efflorescence can be removed through a process called acid washing, which involves using a diluted acid solution to dissolve the salts and then rinsing the surface clean. It is important to note that acid washing should only be done by trained professionals, as it can be dangerous if not done properly. Additionally, it is important to identify the root cause of the efflorescence, such as water intrusion, and address that issue to prevent the efflorescence from returning in the future.