Thought I'd share my review of the heat control window film by Gila.
http://www.gilafilms.com/Residential/wi ... atinum.htm
My south facing windows let in a ton of heat during the summer sun and my wife wanted to buy roll down window shades for the patio door and side windows. I was against the shade because I always felt that a dark room was depressing and I liked being able to see outside. I decided to try Gila Window Film which promised to block out 70% of the heat and blocks 99% of UV rays.
I purchased the film at Lowe's and installed with the help of my wife last summer. I have modern sealed double pane windows, but the instructions say that it can be installed on single or double panes too.
Huge difference in the amount of heat that is blocked! I was so impressed with its performance that I installed the film on all of my south facing windows during this winter. Last week on a 92 degree hot and humid day, I was able to close all the windows in the morning, trapping the cool air in the house and then go nearly the whole day without A/C. Only towards the early evening did the house finally heat up and the A/C was used, which cooled down very quickly and ran occasionally in very short spurts. I credit the improvement to the window film.
The only downside that I can see is that if you live in a cold climate you will not experience the warming effect of the sun on a sunny winter day. The film claims that it reflects 55% of winter heat back in, but I’m not so sure that it is enough to offset the loss of solar heating.
I live in Northern Ohio, but I do not have an issue with the loss of solar heat. I run my wood stove and value being cool on a hot and humid 92 degree day over putting on an extra layer in the winter.
This product would be great for those living in mid to southern states were winters are non-existent or very mild.
Overall I’d recommend it as one of the lower cost energy saving items.