For the glass area, triple gives you a better R-value than double, about
5 versus 3.5.

HOWEVER, the frame needed to support three panes of glass is a better
thermal bridge than what is needed for double. On many windows, the gains
in R-value for triple is offset, or WORSENED by the frame.

If you must have a large picture window, a triple-glazed window would likely
make a big difference. Of course, shutters would also make a big, or even
bigger difference as well.

In our home, our largest windows are 54" x 54" casement (two-section) and
it just made no sense to go with triple-glazing.

--
Calvin Henry-Cotnam
"I really think Canada should get over to Iraq as quickly as possible"
- Paul Martin - April 30, 2003
-------------------------------------------------------------------------
NOTE: if replying by email, remove "remove." and ".invalid"

*** Free account sponsored by SecureIX.com ***
*** Encrypt your Internet usage with a free VPN account from http://www.SecureIX.com ***