Efflorescence is a white, powdery substance that appears on the surface of masonry, concrete or brick walls. It occurs when water-soluble salts within the building materials are brought to the surface by water. When the water evaporates, it leaves behind salts, causing the characteristic of white deposits. Efflorescence is typically harmless but can indicate ongoing moisture issues.
Mold refers to various types of fungi that grow in moist and warm environments. Mold thrives in areas with high humidity and organic material for it to feed on, such as wood, drywall, or carpet. It appears in various colors and can cause potential health concerns.