In theory, at least, window films are an excellent way of boosting the r-value of a room for little money. By covering any windows that may be in a room, you’ve created and extra bit of dead airspace and dead air is a excellent insulation. If you have thermopane windows already in your home, it’s a cheap way to convert them to triple-pane.
Now, in the past, window films didn’t have much going for them. They were often cloudy and showed ripples when you had finished installing them .The newer films, however, are crystal clear and by using a blow dryer, you can get out most of the wrinkles. The end result is very pleasing to the eye, especially if you carefully trim off any excess plastic.
So, for an investment of under $20, it’s possible to improve the insulation of a room considerably. Just make sure before you go to the trouble that you have effectively sealed any cracks or other opening to the outside. Even a small space that lets in cold air can make any other efforts futile.
Some tips when working with films:
1 – This is not a single person project. You will need someone to help.
2 – Make sure to clear all obstructions (drapes, blinds etc) from the area prior to installation. You’ll be glad you did.
3 – Measure the window at least three times to insure you are cutting the plastic to the right size. I measured only twice and still screwed it up!
4 – When cutting the plastic, use a razor blade and not scissors like the package recommends.