Retaining heat loss through the glass in a home has been a problem for many years. First there was secondary double glazing, then there was UPVC double glazing, Recently there has been many adverts on T.V about replacing the windows in your home to install energy saving windows. This could be a very costly way to save energy with a long payback time. Installing window film can achieve the same result for a fraction of the cost with a much shorter payback time without the added cost of possible redecoration. The installation of window film can be undertaken in any weather as the film is applied to the inside of the windows. Glass will filter some of the suns harmful UVB rays but will do very little to reduce UVA rays, window film will reduce both by over 95%, some films can reduce these rays by over 99% another added benefit of film over glass replacement.