Installing Window Film on Insulated Glass
I’m considering putting a heat resistant film over my double pane windows but was told not to since it could blow the seals. Is this true? -Stephanie
Some window manufacturers do not recommend installing heat blocking window film on their insulated glass windows due to concerns that it could cause the inner pane of glass with the film to heat up more than the outer pane. This may result in the two panes of glass expanding at different rates, which could lead to a break in the seal between them or even crack the glass.
The larger the window, the greater the chance a problem could occur. Some types of window film cause less heat to build up than others, so check with the manufacturer to see which ones they recommend for insulated glass.
Also, be aware that applying heat blocking window film to insulated glass may void the warranty on your window, so be sure to check with the window manufacturer first. The warranty provided with some window films is meant to act as a replacement for the coverage that came with the window.