Why coastal windows etch, and when it's permanent
Salt spray doesn't just make glass dirty. Left long enough it etches the surface permanently. How to tell the difference, and what actually prevents it.
The assumption we're testing
“It'll-clean-off-eventually”
Deposit versus damage
Fresh salt sits on top of the glass and comes off with the right cleaner. Leave it through enough wet and dry spells and the salt starts to bond with the glass itself.
Once that happens you are not cleaning dirt off any more. The surface itself is damaged, and no amount of cleaning will bring it back.
How to tell which you have
Clean a small patch properly and let it dry. If the haze goes and only comes back with new spray, it is just salt sitting on top. If a cloudy patch stays on clean dry glass, the glass itself has gone.
Caught early we can sometimes polish it out. Left too long and the glass needs replacing. Near the water, how often you clean matters more than how you clean.
Frames and tracks fail first
Salt gets the metal before it gets the glass. Frames pit, rollers seize up, and locks stop catching.
Near the water, cleaning the tracks and fittings is not a nice extra. It is what keeps the windows opening.
This is The Window Clean Brigade territory.
See the brigade