The Technology Behind Window Film

How does residential window film work? Many homeowners ask this question and it’s a legitimate one. At Home Window Tinting Denver (HWTD), we think it’s important to understand our products.
Large windows in a home can have many advantages. They make homes feel brighter and more open. They can also pose some challenges though, such as overheating which results in big energy bills.

Understanding how window film is made and its advantages is helpful. Window film is a thin layer of plastic, typically PET or polyethylene terephthalate that is applied to the interior side of glass to perform as an insulating barrier against solar heat. Its used primarily to reduce the heat in homes in the summer and is also helpful at reducing fading to floors, furniture, window treatments and even art work.

Manufacturing window film has become very high tech over the years. Window tint has evolved from traditional dye-based, dark or reflective versions to products that are virtually invisible. They are available in varying thicknesses, depending on what level of security you might be looking for, different levels of heat rejection and are also offered in decorative versions, such as frosts, patterns and colors.

So how is window film made? Polyethylene Terephthalate (PET) pellets are melted down and then stretched in polyester sheets. PET is known for its excellent strength and optical clarity. UV blockers as well as dyes and metals are then added to the polyester sheets. Once this is completed the product is then cured in heated ovens. The next step is the evaporative coating, which consist of heating the metal until it melts and forms a gas cloud. Metal gas is then deposited on the film as it cools. In some cases, Electron Beam Coating is utilized. This is the process where high-energy electrons are aimed at the source of metal to vaporize and form a cloud of gas deposits on the polyester sheets.
Some films go through a Sputtering Process where electrically charged gas, such as argon is used to infiltrate the metal and free the molecules. The molecules are then redeposited on the film and layered together to make extremely thin layers of window film.
The final step is to apply a scratch-resistant coating to the film, which makes it long lasting and highly durable.

All of this may seem a bit overwhelming, but If you’re looking for 3rd party validation the National Fenestration Rating Counsel (NFRC) is an excellent source. The NFRC is a non-profit organization that sponsors an energy efficiency certification and labeling program for windows, doors and skylights. They evaluate and rate products from all of the major window film makers, giving you a impartial evaluation of the products available.

Choosing the right solar control window film can be bit confusing, but the window film professionals at Home Window Tinting Denver (HWTD) make it easy! We’ve been helping Metro Denver Area Front Range homeowners select the right product since 1986 and we’re happy to help you make the right selection too!