Is the windshield film applied on the inside or outside?
2 Answers
The windshield film is applied on the inside. If it were applied on the outside, exposure to wind and rain would reduce its lifespan by at least two-thirds. Additionally, if applied externally, glass fragments from an impact could still injure people, rendering the anti-shatter film ineffective. Car window tinting involves applying a thin film layer to the front and rear windshields, side windows, and sometimes sunroofs. This film is also known as solar film or anti-shatter heat insulation film. The primary functions of window tinting are to block ultraviolet rays, reduce heat transmission, and prevent injuries caused by sudden glass shattering. It also serves to protect personal privacy through the one-way visibility feature of solar films.
I've been running an auto repair shop for over a decade, and windshield film must be applied to the inner side of the glass. If applied to the outside, daily wind and rain can cause wear, and the wipers' back-and-forth motion can scratch the film surface. The inner side is cleaner, making it less prone to bubbling after application, and it also reduces UV damage to the film layer. During installation, the technician will thoroughly clean the inner surface of the glass to ensure there's no dust or lint. Many people think applying film is simple, but it actually requires a high-standard working environment—ideally, it should be done in a dust-free workshop. Additionally, it's important to choose a certified film with a light transmittance of over 70%; otherwise, it could pose safety hazards when driving at night.
