Most of the time, installing window film will void the window manufacturer’s warranty but the film manufacturers have backup warranties. That is the simplest explanation of the relationship between window films and window warranties but it is also a completely unsatisfactory explanation of a subject that deserves at least a little more thought. For the purposes of this article, we will limit ourselves to talking about double pane glass: low-E or standard, tinted or clear. Single pane glass rarely has warranty issues while triple pane is rare. We will also assume a standard window film from a reputable manufacturer, such as 3M or Vista. Professional window film installations come with 3 warranties.
- The easiest warranty to explain covers the film itself. Generally, there is a lifetime warranty covering any kind of deterioration of the film. Deterioration can take the form of bubbling, peeling, hazing; all are symptoms of adhesive failure. Fixing adhesive failure requires removing the bad film and reapplying new film.
- The second warranty covers what the film manufacturers refer to as “Thermal Shock Breakage”. Essentially, this means that the film is warranted not to break the glass for a given period of time, generally 2-5 years. The reason why the glass may break is because filmed glass absorbs more heat than unfilmed glass. The added heat stress, on rare occasions, causes the interior pane to crack. Most films designed for home usage are safe on windows, every so often this occurs, generally because of a flaw in the glass.
- The third warranty covers seal failure of the glass. The film manufacturers are aware that many glass manufacturers void their warranties, so every film installation comes with a warranty against the seal failing, which is the main reason why the window warranty comes up in the first place. The standard seal failure warranty lasts for 2-3 years. Even better, Vista and 3M offer warranties that will take over the manufacturer’s warranty at a minimal cost. That way, no coverage is actually lost.