wrote in message
ups.com...
Correct me if I'm wrong, but I thought Low-E windows are the lowest
grade windows allowed? I have always heard Low-E was the lowest quality
and least efficient compared to argon, double pane, etc. This is why
Low-E is the cheapest.


Argon leaks out after a few years.

Double-pane (thermopane) is standard nowadays. Can't really have
"low-emission (low-e)" glass without it since the low-e coating is somewhat
sticky and thus resides on the inside edges of one or both panes. (so I was
told by local glass shop)

I doubt that low-e is the cheapest since it involves an extra coating on the
glass.