Do 3M™ Window Films cause seal failure when applied to insulated (double-pane, Thermopane™) windows?
No, 3M™ Window Films do not cause seal failure. We’ve been applying 3M™ films to insulated windows for over 30 years with several millions of square feet of film applied to date. When recommended films are applied to the inside pane of an insulated glass unit, there will be some absorption (except with 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 degree increase (unusual for most films) will result in a less than 3% change in air pressure, whereas properly made units are designed and tested to withstand 22% changes in air pressure. Put into perspective, most manufacturers of insulating glass units design their products to withstand a pressure change of 3.30 psi, over six times the film’s potential pressure increase. Risk of seal failure is greatly determined by the quality of workmanship and the quality of the materials that
