What is That White Powdery Stuff on My Brick Wall?
We know that efflorescence is a fine, white, powdery deposit (see photo at right) of water-soluble salts left on the surface of masonry as the water evaporates. These efflorescent salt deposits tend to appear at the worst times, usually about a month after the building is constructed, and sometimes as long as a year after completion. Three conditions must exist before efflorescence will occur. If one is left out, efflorescence cannot form.