A Riverside bungalow I surveyed last spring had brick that looked sandblasted on the river side and perfectly ordinary on the street side. Nobody had sandblasted anything. That is what forty years of salt-laden air does when it lands on a wall that never gets rinsed by driving rain.
How airborne chloride gets into a wall
Salt aerosol comes off breaking water and travels inland on the prevailing wind. Concentrations drop fast with distance — most of the load lands within about a mile of open water — but in a river city with a wide tidal reach that covers a lot of housing stock.
The salt lands on the masonry as a fine deposit. Humid air alone will dissolve it, because sodium chloride goes into solution at around 75 percent relative humidity, and northeast Florida sits above that most nights. The solution wicks into the pores. When the surface dries, the salt recrystallizes just under the face, and crystal growth in a confined pore generates enough pressure to break the material apart.
This is the same mechanism as freeze-thaw damage, but it runs year round in a climate that never freezes. It is why coastal brick can look weathered decades before anyone expects it.
Reading the damage
- Sheltered areas fail first. This surprises people. Rain rinses salt off exposed surfaces; under an eave, behind a porch, or on a wall that never gets wet, the salt accumulates and cycles indefinitely.
- The damage is a rounded loss, not a flake. Freeze-thaw pops a plate off the face. Salt crystallization erodes the surface into a granular, hollowed profile, often worst in the softest bricks in the wall.
- Joints go before units on hard brick, units before joints on soft brick. Whichever material is more porous takes the damage.
- White crust in shaded spots is often salt rather than lime efflorescence, and it comes back within weeks of cleaning.
What actually helps
Three things, in order of value for money.
Rinsing. On sheltered elevations, a plain fresh-water rinse once or twice a year removes surface salt before it cycles in. It costs nothing and it is the single most effective thing an owner can do. Low pressure, and let the wall dry.
Poulticing where the salt load is heavy. A clay or cellulose poultice applied wet and allowed to dry draws salt out of the pores. It runs $8 to $20 per square foot professionally, usually needs two or three applications, and it is worth doing before any repointing so you are not sealing salt into the wall.
Repointing in a sacrificial mix. On a coastal wall you want the joint to be the thing that erodes. A lime-rich Type O gives up its surface slowly and can be renewed in thirty years. A Type S joint will outlast the brick and take the brick faces with it.
What does not help: film-forming sealers, which trap the salt solution behind them and blow the face off in sheets; and pressure washing, which drives chloride deeper. I have seen more coastal brick ruined by a well-meant sealer than by the sea.
Getting it priced
Typical numbers here: poultice desalination $8 to $20 per square foot, cut-and-point $15 to $28 per square foot at ladder height, brick replacement $25 to $65 per unit with salvage matching. On a wall that has lost more than a third of its face depth over a large area, rebuilding the outer wythe runs $50 to $95 per square foot.
The sequencing matters more than the line items — desalinate, then point, then leave it alone — and it is worth asking a Jacksonville masonry crew how they plan to handle salt before they mobilize, because a crew that goes straight to pointing has just sealed the problem inside the wall.
Frequently asked questions
How far inland does salt damage reach? The heavy load is within about a mile of open water, but measurable chloride deposition has been recorded ten miles inland on exposed sites. Prevailing wind direction matters more than raw distance — a wall facing the water at two miles can see more salt than a sheltered wall at half a mile.
Is stucco a good way to protect coastal brick? Only if it is a lime stucco that can breathe and is understood to be sacrificial. A cement stucco over salt-laden brick traps moisture behind it, and when it eventually debonds it comes away with the brick face attached.
Will the damage keep going after repairs? Yes, unless the salt is removed or the deposition stops. That is the honest answer coastal owners rarely get. The realistic goal is to slow the cycle with rinsing and sacrificial joints and plan on maintenance every twenty to thirty years rather than expecting a permanent fix.