Cloudy windows that won't come clean

Quick answer: Windows that stay cloudy after cleaning usually have one of four problems: mineral deposits from sprinklers (fixable with restoration compound), salt film near the coast (fixable by washing, not wiping), a failed seal on double-pane glass (not fixable by cleaning; the unit needs replacing), or etched glass from years of untreated minerals (can be improved, not fully reversed). Here's how to tell which you have.

Four things that look like dirty glass and aren't

Mineral deposits: white or rust-colored spotting, worst on the lower half of windows that face lawns or sprinklers. Feels slightly rough. This is the most common cause on the Treasure Coast and it's removable.

Salt film: an even gray haze on glass within a mile or two of the ocean or Intracoastal, worse after windy days. Comes off if it's washed with fresh water first; smears and scratches if it's wiped dry.

Failed seal (fogged double-pane glass): a haze or moisture between the two panes that you can't touch from either side. No cleaning fixes this. The insulated glass unit needs to be replaced by a glass company.

Etched glass: a permanent frosted look, usually where minerals sat for years. The surface itself has been eaten into. Restoration can improve it but can't make it new.

How to tell which one you have

Run a fingernail across the haze. If it feels rough or bumpy, it's mineral deposits. If it's smooth and on the outside only, it's probably salt film or ordinary grime. If you can't reach it from either side, it's a failed seal. If it's smooth, on the surface, and doesn't change when wet, it may be etching.

A professional can confirm in a minute by testing one corner with restoration compound. If it clears, it's deposits. If it doesn't, it's etching or a seal.

What fixes each one

Mineral deposits: hard water restoration with a mineral-removal compound, done pane by pane. Not razors, not vinegar. Then adjust the sprinklers so it doesn't come back.

Salt film: a proper wash, scrub and squeegee, and a quarterly schedule if you're near the water.

Failed seal: a glass company replaces the insulated unit. We'll tell you honestly if that's what you have so you don't pay for cleaning that can't help.

Etching: restoration compound improves the look; heavy etching may warrant replacing the pane.