About 10 years ago when we built our home I had over 50 Andersen windows
installed. Now at least 45 of these need to be replaced because they
have all leaked. Andersen apparently doesn't know how to seal glass
reliably. The mechanism seems to be that the Argon between the panes
leaks out, probably during periods of low barometric pressure and then
as the pressure rises air, which is predominantly nitrogen, can't flow
back into the void between the panes since nitrogen is a much larger
molecule than the argon atom. This "pumping" over many years has left a
substantial negative pressure. The consequence of this is that on low
barometric pressure days Newton's rings are visible in many of the
windows as the two panes approach one another and are separated by
distances or only a few hundred nanometers. Interestingly the larger
widows that Andersen custom made (some as large as 12 feet on a side)
have not leaked. The problems are all with standard production doors
and casement windows.

Unless you can achieve a perfect seal (it can be done but probably not
at home) I'd urge you to back fill with dry nitrogen. Having a way to
re-purge would not be a bad idea either. My vote would be to carefully
look at window manufacturers and evaluate the quality of their product
(Pella and Marvin come to mind) and buy the best you can find. The
effort to make your own may be excessive for what they can be purchased for.

Phil

Zach Tomas wrote:

Myself and LOML are getting ready to build a house. I realize that
when most people say that they mean that their contracter is building
one for them.

I mean we are building it ourselves - basement, foundation, framing,
roof, the works.

She may be wanting some interesting windows and I'm not in the mood to
pay some of the highway robbery prices. Now, building windows is no
trick, but here it is hot in the summer and cold in the winter. I
don't want to lose a bunch of energy through the glass.

Double pane windows are also nothing trick to put together. Shoot,
even the mini-blinds between the panes type that are popular shouldn't
be too difficult.

What I am concerned about is the fogging and water between the panes
from condensation.

I have considered:

a. Assembling them inside a sealed box purged with nitrogen.
(with gloves attached to arm holes)

b. Making the inside pane hinged for periodic opening/drying.

c. Attaching a fitting, tubing that runs to the attic, and tire
valve at the end. Once a year, go to the attic and recharge
the windows with nitrogen or CO2.

d. I am just nuts to begin with. (Make that "eccentric")

Thoughts?

-zach