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Common Water Issue in BC
White Chalky Deposits on Foundation Walls (Efflorescence)
Efflorescence appears as white, powdery, or crystallized deposits on concrete or masonry walls. It is caused by water migrating through the concrete, dissolving mineral salts, and depositing them on the surface as the water evaporates. Efflorescence is direct evidence that water is moving through your foundation — it is the visible trace of an invisible moisture path.
Possible Causes
- •Hydrostatic pressure forcing groundwater through foundation walls
- •Failed exterior waterproofing or drainage system
- •Foundation cracks allowing water entry with mineral transport
- •High water table seasonally saturating below-grade concrete
- •Improper interior sealing trapping moisture within the wall
Recommended Steps
- 1Brush off loose efflorescence to monitor if it returns (active water flow)
- 2Address exterior drainage — gutters, downspouts, and grading
- 3Do not apply interior waterproofing paint over efflorescence — it traps moisture
- 4Schedule a foundation moisture assessment to determine the water source and flow path
Need Professional Help?
Don't let a small leak become a big problem. Contact LeakInspections.ca — a division of Anyleak.ca and Leak.ca — for expert diagnosis.