A wide variety of Solar Control Window Films are available, they range in colour and tint and they offer greater or lesser protection from the three causes of fading (heat, Light & UV) depending on the type you opt for.
First things first BEWARE CHEAP IMITATIONS! The Market has been flooded over the last few years with cheap copies of the most popular types which are massively inferior to the originals. A good way to check is to ask how long the warranty is against cracking, peeling & de-lamination. If it is less than 8 years on vertical glass for internal application then walk away.
The main reason for the cheap films inadequacy revolves around the one issue that ALL window films should solve UV.
All internally applied window film should have a UV filter built into the adhesive to protect itself from the damaging effects of UV. A film without that filter will last months before discolouring and peeling off. The fantastic benefit of that need to protect itself is that the film will also protect anything behind it from damaging UV up to about 99%.
Our boss, Steve can testify to the effectiveness of the UV filter because he installer completely clear security film on his living room windows which faced south west and had a dark blue cloth sofa up against them. When, after 5 years he decided to update the sofa he was amazed to find that the sofa was still the same colour at the back as it was at the front. This would seem to prove that UV is far more destructive than heat and visible light.
There are some situations when a dedicated "anti-UV" film is required which has an improved filter to stop 99.8% of UV but this is usually reserved for sensitive applications like laboratories etc.
This benefit of window film can not be underestimated. A solar reflective window film, even internally mounted, can make a massive difference to the heating effect of the sun in a room or conservatory. Physics tell us that if we can prevent heat from entering a room in the first place then half the battle is won. By installing a film designed to reflect the suns rays directly onto the glass, we are preventing up to a full 80% of the suns heat from entering your home. Most films contain particles of a metal, either silver, stainless steel of gold which is "sputtered" onto the surface of the film. These particles of metal directly reflect the heat. The greater the concentration of sputtered metal particles, the better the heat reflection, and the darker the film (we will look at the darkness of the film in "GlARE" below. Some new developments in window film technology in the last 5-8 years have seen the introduction of a film which works differently. The film is sputtered with ceramic particles which, rather than targeting all heat are spectrum specific, in that they deflect Infra red radiation at a up to a certain bandwidth. This area of bandwidth is responsible for the heat and so without affecting the tint on a film (how dark it is) up to 55% heat reflection can be achieved.
We all know the best way to prevent glare at a personal level. That's right, put some sunglasses on!
Solar Control Window Film has much the same function as sunglasses and the darker the lenses the more glare is reduced and the less light is allowed in. In a conservatory situation we would always suggest that the best heat reflecting film, which will also be the darkest is used on the roof. "But won't this take all of the light and airy feel from my conservatory!" we hear you scream! Actually no, because in a conservatory you tend to have walls that are also made of glass and thus there will always be enough light coming in. For example the best performing film is "SILVER 20" this film will reject up to 80% of solar heat, reduce glare by 70% and, as with all films cut our 99% of UV.