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Frequently Asked Questions

What is window film?

The vast majority of window films are made up of several layers, which will nearly always include a polyester ‘base’ sandwiched between a scratch-resistant coating (SR) and adhesive systems, which adheres the film to glass. Depending on the film type, there may also be metalized and dyed laminates.

What are they for?

Films can broadly be divided into 4 types: solar control, safety/security, automotive and privacy. Advances in manufacturing techniques now allows for 2 or more of these types to be combined into one film.

Solar control films are designed to reduce incoming solar heat, glare and ultra violet (UV). They are available in many colours and tend to have 3 or 4 ‘strengths’ per range- from high-reflective to very light. Solar films can totally transform a building by giving it a uniform colour and hiding untidy looking office environments- such as the backs of work desks, wiring, etc. Many buildings can benefit financially from an application of solar control film in the form of reduced air-conditioning costs.

SAFETY/SECURITY films range from 50 microns to 350 microns and more. They are extremely tough and hold glass together in the event of accidental or malicious impact. Safety/security films are used extensively in commercial buildings to bring glazing up to current British and European safety standards. The heavier gauge films are often specified in high-risk areas such as banks and government buildings. They resist unwanted entry and protect occupants from terrorist and accidental explosions.

An increasing number of motorists are benefiting from automotive tints applied to their vehicles. Besides improving a vehicles appearance, automotive films can significantly reduce incoming solar heat- making it more comfortable for passengers and reducing fuel bills by lowering a/c usage. By virtually eliminating UV, your vehicles interior will look better for longer. Also, a dark tint to the rear of your vehicle will distract unwanted eyes on the contents of your rear seats or boot space. Automotive films are also available in safety/security versions, creating a safer environment for you and your passengers.

From totally opaque to a light sand-blasted appearance and available in every colour imaginable, Privacy films offer an attractive, cost effective solution for creating privacy or hiding areas of a building. Typical applications include cloakroom privacy, hiding curtain-walling behind large panes of glass and creating private areas within office environments.

How are they applied?

Films are applied with a mild soap/water solution and squeegeed onto glass after removing the backing sheet. Whilst small applications are possible by any keen DIYer or tradesman, we would certainly recommend employing a professional company for larger applications or areas where a quality finish is vital - such as retail or modern office areas. We do not recommend any DIY automotive applications. for more info on application techniques

I think I need a solar film but don’t want a mirrored look.

Whilst a silver solar film can make a building look very modern it would not suit a domestic application or an old, historic building. However, there are several neutral films available which can give maximum protection yet are hardly noticeable. Also, sputtering technology has led to several high-performance films which are extremely light.

How long will it last?

Window films are extremely durable and typically last 5-10 years and more, depending on where they are applied. There are documented cases of films lasting 22 years.

What happens if I want it removed?

No problem. The film itself can be pulled from the glass which will generally leave adhesive residue on the glass. This is removed by spraying with soapy water and using a razor-scraper. No need for any over-powering adhesive removers.

Can I clean the window after a film is applied?

Yes, using a soft, clean cloth or paper towel to clean and the same or a rubber squeegee to dry. Use mild detergent or every-day glass cleaning solutions. Basically, avoid using abrasive tools and chemicals.


Flat Glass Terminology

The following provides a glossary of terms often used when discussing Flat Glass films:

Visible Light Transmission

Visible Light Transmission (VLT) is the percentage of solar visible light (daylight) that passes through a glazing system.

Solar Energy Rejected

Solar Energy Rejected (TSER) is the percentage of total solar energy (heat) that is rejected away from a glazing system. This equals solar heat reflectance plus the amount of solar heat absorbed that is then re-radiated outwards.

UV Light Protection

UV Light Reduction is the percentage of Ultraviolet Rays that is rejected away from a glazing system.

Exterior Reflectance

Exterior Reflectance is the percentage of reflectivity (mirror effect) that occurs on the outside of a glazing system.

Interior Reflectance

Interior Reflectance is the percentage of reflectivity (mirror effect) that occurs on the inside of a glazing system.

Solar Absorption

Solar Absorption (TSA) is the percentage of total solar heat that is neither transmitted through nor rejected away from a glazing system (i.e. the percentage of total solar heat absorbed by the glazing system).

Solar Reflectance

Solar Reflectance (TSR) is the percentage of solar heat that is reflected away from a glazing system.

Solar Transmission

Solar Transmission (TST) is the percentage of solar heat that passes through a glazing system.

Shading Coefficient

Shading Coefficient (SC) is the ratio of solar heat gain passing through a glazing system to the solar heat gain that occurs under the same conditions if the window were made of clear, un-shaded double strength window glass (lower SC equals better solar shading performance).

Solar Heat Gain Coefficient

Solar Heat Gain Coefficient (SHGC) is the percentage of total solar heat that enters a glazing system. This includes heat directly transmitted as well as heat that is absorbed by the glass and then transmitted inwards (lower SHGC means less heat transfer from the exterior to the exterior).

U Factor

U Factor or (U Value) is a measurement of solar heat transfer due to outdoor/indoor temperature differences. It's the amount of heat passing through one square foot of glass in one hour for each 1 degree Fahrenheit temperature difference between the indoor and outdoor air (the lower the U Value, the less solar heat passes through a window).

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