Is window film applied to the exterior or interior?

Window film is typically installed on the inside surface of glass, in both buildings and vehicles. However, dedicated exterior window film is available for certain special circumstances, such as if it is difficult to obtain access to the interior side of a window, or if the type of glazing does not lend itself well to window film being applied on the inside surface.

As one of the premier suppliers of window film for both interior and exterior application here at Opalux, we can advise you on which type of film may best serve your specific requirements.

Don’t get these two types of window film mixed up!

If there are any questions our technical team is asked almost as often as “is window film applied to the exterior or interior?”, they are “Can I apply internal films externally?” and “Can I apply external films internally?”

Unfortunately, we do not recommend that you apply interior window films on the outside surface of glass. This is because the different way in which internal film is processed compared to external film means it would not be able to withstand the ravaging effects of external weather and ultraviolet (UV) rays. Interior window film applied outside would therefore have a much shorter lifespan than exterior film installed in the same setting.

It is, however, possible to apply external window films internally without any adverse issues.

In what specific circumstances may I buy external window film?

A good example of exterior window film is our External Reflective solar control film that can be specified in Silver 20 (SO-20RS-eSR) or Silver 35 (SO-35RS-eSR) variants. These films are of weather resistant construction, incorporating the additional UV barriers required to protect them from degrading due to exposure to the sunshine; they also have a strong water resistant adhesive.

We routinely recommend that our customers purchase these exterior window films over their internally applied equivalents if inside access to the glass isn’t possible, or if the glass is laminated, heavy tinted or Georgian-wired. Certain double or triple-glazed windows may also be best suited to window film being applied externally rather than internally.

Ask the Opalux team today for specialised and informed guidance

If you are still confused or unsure about any aspect of whether window film should be applied on the inside or outside surface of your own building or vehicle’s glass, please consult the dedicated page of our site for exterior-grade window films. 

Alternatively, simply fill in and submit our online contact form or give us a call, on 0845 026 1125. We will then be able to advise you on which of our highly rated products may best suit your needs.