Many factors determine how long before you will earn your investment back after installing 3M™ Window Films in your home.  The surface area of your windows and their orientation play an important factor as well as type of window film  purchased and glass installed.  With these variables considered on average you will see total energy cost savings equal to your investment within two to five years.  Property owners with large west-facing windows  have reported a payback period of less than 6 months!