Thank you. I did read the material. But since each of these panels are about 6 feet tall and mounted in heavy woodwork (they don't open) I do not feel capable of replacing them myself... in fact I think it would be dangerous. Maybe one day I'll get the nerve to try, but to me it seems like a job for a pro. Thus the big bucks. They call these "smart" windows. But if I replace them I may have single pane put in. It reminds me of "Fool me once, shame on you. Fool me twice, shame on me." Another scary thought is that every window in this house is double pane. And there are LOTS of them. A quick count of the upstairs alone is about 50 (so many because most windows have multiple sections) I have actually had nightmares over this! Again, thank you.