I had some double glazing units replaced by a local firm when I moved into my house about 8 years ago. The ones I replaced had obviously failed as condensation was forming on the inside.
Now the same units have become misty again - no condensation as such, just a faint film on the inside which looks very ugly (particularly in sunlight). A glazier who came to look at them told me that this was quite normal and that one couldn't expect any double glazed units to last more than 8 to 10 years. Is this true? Are there cheapo units around that will fail more quickly? (Or conversely more expensive ones that last longer?).
I would appreciate any advice before I go ahead and replace them again. Thanks