film on window glass?

[John Arnold]

I don't have a good photo.
Newer double pane double hung windows with vertical wavy pattern on glass. Did not look like a bad seal. Almost looked like old glass, but it's not. Am I looking at some kind of film or energy saving coating? I'd be surprised if the owners had sprung for anything but the cheapest windows.

[Jim Luttrall]

Some high eff. windows have a film suspended between the panes with a low-E coating, any chance of that?
The Efficient Windows Collaborative (http://www.efficientwindows.org/glazing_.cfm?id=10)

[Rick Hurst]

John,

If it has a rainbow looking effect to it, it is a bad e-low film on the windows.

rick

[John Arnold]

Thanks Jim and Rick -

No rainbow effect. Perhaps I didn't take enough of the ... never mind.

Just a clear vertical waviness all across the glass. Groovy, man.

[Matt Fellman]

Some of the newer 'Low-E' windows have really strange looking patterns and colors when the seals fail. In the old days it was just moisture and mineral deposits which were easier to ID. Some of failures I've seen lately have almost a metallic look, almost like spray paint.