How to clean the inside of a double pane window
When a window seal breaks, moisture and residue build up permanently between the glass panes where no cleaning tool or solvent can reach. Because the trapped film is sealed inside the insulated unit, homeowners cannot wipe it off and must ultimately replace the glass to clear the view.
What the numbers show
Counted from the threads quoted below. How we count
- Most of it landed at once — the busiest month was September 2026, with 6 people.
- This comes up 16.0× more often in r/homeowners than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Replacing the entire glass unit2 people mentionedDid this help you?
- 2Applying a privacy film with a pattern over the glassDid this help you?
- 3Leaving the window alone as a purely cosmetic issue until replacement is possible.Did this help you?
- 4looking for repair adviceDid this help you?
- 5hoping this is something we can do on our ownDid this help you?
- 6Spraying small sections of the exterior with a hose while watching from the inside to isolate the entry point.Did this help you?
- 7Trying to scrape off the residue with a razor bladeDid this help you?
- 8Call a professional to inspect and fix the issue.Did this help you?
- 9Learn how windows are supposed to be installed to diagnose and repair the separation yourself.Did this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“It is in between the glass. It is a broken seal and makes this window not insulate as well.”source ↗
“some kind of privacy spray? Tent? Paint thinner, and acetone does nothing to touch it. tried a few different types of razor blades as well”source ↗
“Our Chandelier window looks like this. Does anyone have an idea what is going on here? I attempted to use a razor blade in the corner thinking maybe it was some window tent that failed, but I was unable to remove anything. Is this a failed window in between the glass? Anyway to fix this or do I have to have the whole window replaced?”source ↗
“Mine was like that and it was due to moisture getting in and rust all around it. We replaced it”source ↗
“Been raining somewhat consistently and we notice that water is leaking from the top corner of our bedroom window”source ↗
“Went outside and noticed that the corner of the window has somewhat separated from the wall.”source ↗
“Is this something I could do on my own or better to call a professional?”source ↗
“My outside windows have some patterns that I can’t clean off.”source ↗
“I think it might be some damage to a coating but I can’t feel it on the inner or outer pane. It might be inside between the panes.”source ↗
“Anyone seen this before and know what caused it? Is there a way to fix it or is the only option window replacement?”source ↗
“We just had some rain and it was leaking through the caulk cracks. I know that needs repaired but water is getting in somewhere.”source ↗
“During a recent rain storm, I discovered a small water leak coming in through an old screw hole from an older set of blinds.”source ↗
“I suspect the window flashing but I'm seeing what anyone else may think.”source ↗
“The leak seems new, as there's no staining and I've never noticed it before today.”source ↗
Where this came up
People with this problem also raised
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