How window films work

Window fillms

How window films work

To understand how window films work, we need to understand a little more about windows and light.

It seems that windows these days are made of an amazing variety of different types of glass.  Some windows are clear, others are totally reflective, and yet others feature what seems to be an infinite range of tinting.

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Studies have shown that inefficient windows can waste anywhere from 25% to 35% of a building’s energy budget.  Solar heat gain through windows accounts for nearly 40% of a building’s cooling requirements.  How do window films help?

Sunlight consists of ultra violet radiation (UV), visible light and infrared radiation.  Our eyes only see visible light.  Blocking visible light from entering a building is easy, we have been doing it for years, but it makes the inside of the building dark.

From an energy standpoint, visible light is not the major culprit when it comes to heat gain in a building.  You have probably noticed that a curtain or a blind blocking light is warm.  What you are experiencing is the effect of the other two components of sunlight – infrared and UV radiation.

Visible light makes up about 44% of sunlight, infrared makes up about 53% and UV makes up the last 3%.  While you might not think that UV radiation would be that much of a problem, it has a very short wavelength and, as a result, is highly damaging.

UV radiation has been shown to have negative health effects and is the primary cause of fading to interior fabrics and colored components.

There are essentially two different ways that window films work. Some heavily dyed or colored films reduce light transmission by absorbing solar energy. Proper reflective window films are coated with microscopic metals.  Instead of absorbing, they actually reflect light, and depending on the amount of metals introduced, produce very effective results.

Effective, energy efficient window films reject UV and infrared radiation while allowing for as much visible light to enter a building as possible.

I am looking forward to reviewing window films, buttoning down their best features, what makes them green, and then providing FAQs and tips and tricks to give my readers a full understanding of this green living product.

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Please continue reading my Window Films Reviews, their best features, what makes it green, FAQs, plus tips and tricks to give my readers a full understanding of this green living product.

Please see our other review posts for this living green product:

Best Features of Solar Window Films

Features that make Reflective Window Filmsgreen

Low E Window Film FAQs

Window Insulation Films Tips and Tricks

Thank you for visiting, and finding time to  Switch it Green, Switch it Forward.


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