With the relatively wet spring we’ve had this year, you might be noticing a white, chalky substance on some of your stucco or cement walls. What the heck is that? It’s called efflorescence and it may or may not be a big problem. So what causes this phenomenon?
When moisture gets in through cracks in concrete, stucco or other porous construction material, or gets wicked up from the ground, it brings dissolved salts and minerals to the surface. When the moisture dissipates, you’re left with the white residue. It usually scrubs off easily. It may simply be a cosmetic issue, or it could indicate a larger structural problem caused by moisture intrusion. Home inspectors should take note of efflorescence in their report. You may want to consult a concrete or masonry specialist before you buy a home that shows signs of efflorescence.