Stucco Repair • 5 min read
Why White Powder Appears on Stucco
White powder on stucco is usually efflorescence: mineral salts carried to the surface by moisture moving through masonry or exterior cladding.
Get help with Stucco RepairWhat efflorescence means
Efflorescence is a visible clue that water is moving through or behind the stucco surface. It is not always an emergency, but it should not be ignored.
Common causes
Moisture intrusion, poor drainage, failed sealants, missing drip details, and trapped water can all move salts to the surface.
- Moisture intrusion
- Masonry salt deposits
- Failed caulking
- Poor drainage details
When to call a contractor
If white staining returns after cleaning, appears around cracks, or is paired with soft/delaminated areas, the wall should be inspected before more damage develops.
Next Step
Need this inspected on your property?
Send photos and your city through the quote form. City Plasters will review the wall condition, access, and scope before recommending the right repair or installation path.
Related Resources
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