Windows still cloudy after cleaning? What the haze is telling you
Cloudy glass after a clean is one of three things: mineral or metal-oxide film, which the right treatment removes; etching, where salt or hard water has permanently marked the glass; or fog between double-glazed panes, which means the seal has failed and no cleaner can reach it. A proper clean fixes the first, softens the second, and can only diagnose the third.
Three kinds of cloudy, and only one of them is dirt
Stand at the glass and do three checks. Wipe a wet finger across the haze — if it clears for a moment and creeps back as it dries, you are looking at surface film. Run a fingernail over any spots — if you can feel texture that will not shift, the glass itself is marked. And if the fog sits where neither an inside nor an outside wipe can touch it, it is trapped between the panes. Three different problems, three different answers, and only the first one is cleaning.
The wrong diagnosis wastes money in both directions. Homeowners scrub at internal condensation for years, blaming their cleaner, when the glazing unit failed long ago. Others live with a milky film they assume is permanent damage, when a restoration clean would strip it in an afternoon. The haze does not announce which one it is. The tests above get you most of the way; a cleaner who knows glass gets you the rest.
Film: the buildup a squeegee cannot shift
The most common culprit is water itself. Sprinkler overspray, a hose-down that dried in the sun, rain sheeting off a rendered wall — every pass leaves a trace of dissolved minerals behind when the water evaporates. One pass is invisible. A few hundred build a white, hazy crust that bonds to the glass and shrugs off ordinary detergent. It looks permanent. Mostly it is not — it needs a specialist mineral treatment and patience, not a stronger arm.
The second film comes from metal. Rain washing over aluminium frames, ageing flyscreens or a coated-steel awning carries fine oxides down onto the pane below, where they dry as a grey or rusty veil. Coastal homes collect it fastest, because salt accelerates the corrosion that feeds it. Like mineral spotting, oxide staining sits on the surface — which means the right chemistry removes it. It is slow, careful work, and it is why 'we cleaned them and they still look cloudy' is often not a cleaning failure at all.
Etching: when the surface itself has changed
Etching is different in kind, not degree. Leave salt spray, hard-water deposits or alkaline runoff on glass long enough and they stop sitting on the surface and start reacting with it, leaving micro-pits and a permanent dullness. Ocean-facing windows in Bronte or Manly that have gone years between cleans often carry some. Hold the glass to low sun and the difference shows: film wipes away to a clear patch, etch stays in the reflection like a ghost.
We will not pretend otherwise: no clean reverses etch. Light cases can be improved with polishing; heavy etch is a conversation with a glazier, not a cleaner, and anyone promising to wash it out is selling. What a regular clean does is stop the clock — salt that never sits for a season never gets the chance to bite. That is the real argument for a routine on coastal glass, and it is a better one than fear: the cheapest etch repair is the one you never need.
Fog between the panes is a glazier's job
Double-glazed units are sealed with a drying agent inside the cavity. When the perimeter seal fails — age, building movement, sun — moisture gets in, overwhelms the desiccant, and fogs the inner faces of the unit. You can polish both accessible surfaces to perfection and the cloud stays, because it lives in the one place a cloth cannot go. It often comes and goes with the weather, which is the giveaway: dirt does not care about the temperature.
The fix is a glazing one — usually replacing the sealed unit itself, not the whole frame. Our job in that situation is to say so plainly. When we find a failed unit on a window round, we point it out, because charging to re-clean glass that cannot come clean is not a service, it is a subscription to disappointment. Good exterior care includes knowing where cleaning ends and the trades begin.
What a proper clean costs, and what to do first
A proper clean — pure water, the right chemistry for mineral and oxide film, tracks and screens done rather than skipped — resolves most cloudy glass, because most cloudy glass is film. Window cleaning starts from $150, and most single-storey Sydney homes land between $150 and $550 depending on window count. Two storeys adds about 40%. If a pane needs mineral restoration, or turns out to be etched or blown, you will hear it straight — not discover it on the invoice.
Start with the wet-finger, fingernail and between-the-panes checks — two minutes at your worst window tells you which problem you own. If it is film, cleaning solves it. Then get your number before anyone visits: the Schmick instant quote returns a firm, bookable price in about 60 seconds, and it holds unless the place is materially different from what you told us. Cloudy glass has three causes. One of them is fully ours to fix — and for the other two, you will get a straight answer instead of a repeat invoice.