Reflective Window Films

All film types reflect and absorb solar energy to some extent, but reflective films are more reflective than absorptive. Single reflective films have the same reflective surface on both sides of the film and so have similar qualities on both sides.

A reflective film is the one needed for one way privacy. The amount of privacy, or reflection is dictated by the amount of tint, and the difference in light on each side of the glass. If you're standing in your garden, on a bright day and it's dark inside the house, you'll see a reflection when looking in (referred to as daytime privacy) and a tint looking out. The greater level of tint, the greater level of reflection from outside and the darker it will be when looking out.

As it gets darker outside and the light levels between inside and outside start to equalise, the level of reflection, or privacy, from the outside will start to diminish and the view looking out will start to become reflective. When the light levels are the same on both sides, the appearance will be the same on both sides. A sort of reflective, tinted effect.

​When it's fully dark outside and you have the lights on inside, you'll be able to see in from outside and when trying to look out, you'll see a reflection of yourself. You will already see a reflection in plain glass in these circumstances as plain glass has 8% reflectance. A 20% single reflective film (lets in 20% light) has around 50% reflectance.

The greater the level of tint, the greater the level of reflection, from films with 60% VLT (visible light transmission) all the way down to 10% VLT that are sold as one way privacy films or the ones you see on TV in the police interview rooms. These films only work when the bad guy is in the well lit room and the police sit in a dark room.

Another example is a household mirror which would be the equivalent of 0% VLT. It's a piece of glass (think of this as your window). The glass is painted silver on the back (the reflective film) and is then painted in dark paint (a very dark room).

Don’t practice this at your neighbour's house but what do you do if you want to look through a window at night? You cup your hands round your face and get close to the window - but why? It blocks out the light in that area making it darker. If it’s darker than inside the room, you can now see in!

Single reflective films are usually some of the most cost effective solar control films to install and have the best qualities in terms of heat and glare rejection, daytime privacy and heat gain coefficient (the reflective qualities reduce heat loss back through the glass) and, as the energy is being reflected away from the film, the surface doesn't get too hot.

Single reflective films are a great choice for conservatory roofs, on any vertical glass where blinds or curtains can be used to hide the internal reflection at night or indeed, if you don't mind the internal reflection. Just be aware that at night, people can see in and you can't see out.