The core idea
White crystalline deposits show that water dissolved salts and evaporated, but they do not identify the exact source or current wetness.
How the mechanism works
Water moves through masonry, carries soluble salts and leaves them at the evaporation surface.
When it becomes relevant
Typical trigger: Ground moisture, rain entry, leaks or drying after construction.
Evidence that supports this interpretation
- Deposits recur after wet events
- A moisture gradient exists behind them
- Drainage defects are nearby
Evidence that weakens it
- The material is non-mineral
- The deposit is paint or biological growth
- No water pathway exists
What this concept cannot prove alone
A single observation, image or meter reading cannot confirm the complete failure pathway. Use this concept to form better questions, compare alternatives and decide which safe observation would be most informative next.
Safety and professional boundary
Do not seal recurring deposits behind impermeable coatings before the moisture route is addressed.
Primary references for this topic family
These references ground the general building-science or safety context. They do not diagnose a specific house, replace local requirements or certify a repair.
