+1
Impossible to say without inspecting the roof but some will live quite a long time based on exposure, correctness of installation, ventilation, etc.
There is quite a bit of variance and human cont ... read more
Abe nailed the answer for you.
If the windows are due for replacement, look for a window with offset glazing or an option of laminated glass inside the standard set of windows.
Dedicated STC windows w ... read more