Annette,
I'm surprised you have not tried Stegbar.
looking at the other manufacturers I surmise you don't want wooden frames that require maintenance.
Anyway They were the second cheapest manufacturer I approached 12.5m^2 U = 1.9-2.0 SHGC=0.35-0.4 and the visible transmittance escapes me right now. Cedar Frame.
They were about 110% price of cheapest (EuroTech) and the most expensive (Parhammer of course) was ~280% of cheapest.
Trend of EuroTech would have been my next two choices.
IMHO argon filling is overcomplex and overpriced for the small gains made and may simply leak out over time (unsubstantiated).
Remember that visible transmittance is a very important metric: If your after views then god speed to you however if you are looking to brighten your rooms and your super-low U-value windows have a Visible transmittance of only 10% then perhaps you would be better with a smaller, cheaper plain single pane window?
Lastly remember no matter how insulating a window is it will always be the Achilles heel of your buildings thermal performance. I wanted to leave windows out of a few rooms in new house however Aust building standards state windows must be 10% floor space.
Try calculating heat loss per element of build (walls, roof, floor, windows, doors .etc) and see what the figures are, may be an enlightening exercise. Also windows are a very expensive element of build, try not to go crazy, unless you enjoy your day job and large mortgages.
Good Luck to you Old Bean
Posted Wednesday 8 Feb 2012 @ 4:22:00 am from IP
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