(I suppose technically this isn't a repair question--but if I try this
I'll probably break something and need repaid advice, so might as well
start here! :-))

I've got a room with a couple windows--one is a view-only window
(nothing that opens), and one that is a more regular window with a
sliding section and a screen. The latter has some kind of storm window
on the outside, so there is a layer of glass, an air gap, and the inner
glass. The view window also has an outer and inner layer, but it is not
sealed, and it is just regular air in there, not some special gas.
(I've seen spiders in there, so know there is a connection to outside).

In winter, I have no need to look out these windows. The blinds are
down all the time (and I wish the blinds were more effective--if I get
bright sunlight, it makes it hard to see the TV and the computer screens
in the room).

I'd like (1) less heat loss through the windows, and (2) less outside
light in the room. Could I kill two birds with one stone here by
covering the inside of the windows with some kind of insulation? Maybe
make some kind of temporary wall-type structure out of a couple sheets
of plywood with insulation between that would fit in the window frame,
on top of the sill, that I could easily put up in winter and take down
in summer? Or something along that general idea--maybe just one sheet
with insulation behind it? Or maybe just put up sheets of insulation
right on the window, held in place by tape, and covered by the blinds so
it doesn't look ugly? Any pitfalls to avoid (like inadvertently causing
a lot of condensation some place that I really don't want to have
condensation?)

Am I at least going in a decent direction here, or is the whole idea
nuts, and I should just get new windows if I want to reduce heat loss,
and get some good curtains if I want dark?



--
--Tim Smith