"Ted Jackson" wrote in message
...
I live in an area where it gets really hot on some days. Some people place
black film on their windows to keep out the sun. There is a local company
that is selling totally black window screens that cover the entire window.
Those screens look great but I have a question:

Are such screens a great idea for keeping out the heat or is it just a
scam to make lots of money replacing regular screens with new screens that
cover the entire window?? On some types of windows, it means the new
screens would be twice as large as the older screens now on the windows.

Sounds like BS to me. Black screens are often used for style, because they
sorta 'vanish' when you look through them. Putting such a screen over entire
window on outside would work about like a windowshade on the inside,
reducing the transmitted sunlight to a degree. Of course, if the screen
doesn't pass air real well (like when it gets clogged with spiderwebs and
such), it will also function as a solar collector, heating the air layer
next to the glass. They put black privacy film on the frosted glass in some
of the toilet stalls at work, and you can't even use those stalls on sunny
winter days anymore- the glass itself gets superheated, and heats to stall
space to 90+.

If sun load through certain windows is a big problem, the traditional
solutions of screening vegetation or an awning, or the modern solution of
reflective film, would probably do more good.

aem sends...