re: "solar drapes"/shades a reasonable idea???
15 mar 2003
>for ideas on shades, there is a book:
> "thermal shutters and shades", shurcliff, 1980, brick house
>publishing, 240 pages...
>it has "over a hundred" schemes and designs for various kinds of
>shades and shutters -- some of them are very innovative.
the best (imo) being scheme 18.7 on page 168: 5 sheets of metallized mylar
with springy spacers that unfold when it is rolled down. scheme 18.8 on page
170 (a self-inflating mylar shade) also seems interesting. alas, these are
no longer being made. perhaps they can be recreated with a $118 -rs1 hot
roller for plastic film seam-sealing from hillas at (800) 952 7274.
>symphony shades has a clever design for a duofold style shade called
>energy track. the shade incorporates a track on each side of the
>window to reduce air circulation between the cavity between the shade
>and the window and the room...
>if i try to compare the cold air flow into the room at the edge of the
>shade between the symphony shade and a conventional duofold shade, it
>does appear to by less for the the symphony, but i can't say how many
>btus per hour this translates to. if anyone has a good quantitative
>way to measure how much the energy track feature saves, i would be
>interested in hearing about it.
i called them at (877) 966-3689. they say their room darkening shade has
an r-value of 3.2 when used with an r1.8 window. this increases to r4.8
with side tracks. a 3'x6' shade costs $107 without the side tracks and
$170 with. the max window width they can handle is 96".