Do Vista Window Films cause seal failure when applied to insulated (double-pane) windows?
No, Vista Window Films do not cause seal failure. It has been applied to millions of square feet of glass and it has not been known to cause seal failure. When recommended films are applied to the interior pane of an insulated glass unit, there will be some absorption (except for clear safety films) of the sun’s energy, which will increase the temperature of the glass pane. Some of this heat will transmit to the airspace, slightly raising the airspace temperature. However, even a 20°F increase (unusual for most films) will result in less than 3% change in air pressure, whereas properly made units are designed and tested to withstand 22% changes in air pressure. Risk of seal failure is greatly determined by the quality of workmanship and the quality of the materials that go into building the insulated glass units. The best guard against seal failure is to purchase well-made units from reputable window manufacturers that have solid experience and histories with insulated units.
