Window film

Window film is a thin laminate film that can be installed to the interior of glass surfaces in automobiles and boats and also to the interior or exterior of glass in homes and buildings. It is usually made from Polyethylene Terephthalate (PET), a thermoplastic polymer resin of the polyester family, due to its clarity, tensile strength, dimensional stability, and ability to accept a variety of surface-applied or embedded treatments.

Window films are generically categorised by their construction components (dyed, pigmented, metallized, ceramic or nano), by their intended use (automotive, marine or architectural), by substrate type (glass or polycarbonate), and/or by their technical performance (privacy, solar control, safety and security).

Window film is normally installed by professional service companies but there are also D.I.Y. kits widely available.

The International Window Film Association, founded in 1991, provides unbranded information about window films.

There are many different grades, shades, colours, and thicknesses of available window films built to offer solutions to a variety of challenges. Window films are a retrofit upgrade for existing glass that can be used to address problems inherent to glazing, including:

Window films are an extremely cost-effective method to reduce heating and cooling costs in existing buildings by reducing the amount of heat transfer through glazing.

Heat rejection films are normally applied to the interior of flat glass windows to reduce the amount of infrared, visible light, and ultraviolet (UV) radiation entering windows. Such films are usually dyed or metalized (which can be transparent to visible light) to convert incoming solar radiation to infrared radiation, which is then rejected back through the glass to the exterior. Modern window film technology has created ceramic window films which are non-metallic and do not contain dyes that can result in discoloration. The ceramic and metallic window films usually cost 10–15 percent more than regular window film but can reduce energy transmission by as much as 80 percent. Ceramic window films cost slightly more but provide a substantial increase in blocking UV rays and ability to control heat transfer.

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Wikipedia