Originally Posted: 12/04/2008
Having been through the majority of forums relevant to the topic on this website, as well as interacting with customers on a daily basis, I have noticed that there are a few common misconceptions regarding window tint in the UAE. This forum is dedicated to clarifying your tint queries – so feel free to post here or PM me. However, this forum is not meant to promote or denounce any particular tint brand, so I will not answer questions such as “Which is the best window tint?” – This is for you, the consumer to decide.
Below are 5 of the most common questions I hear on a daily basis.
1) How dark can I tint my windows in the UAE?
30% is the magic number. To understand what this means, you would need to understand the term VLT.
To understand this UAE law it is important to recognize the concept of Visual Light Transmission (VLT). VLT is the amount of light that can transmit through the window. A VLT of 50% would mean that 50% of light can flow through the window; the remaining 50% is either absorbed or reflected. Similarly 70% means that 70% of light flows through and only 30% is blocked or reflected.
Most reputed tint companies are well aware of the UAE law and the fact that it is based on VLT. In fact, when they order their stock from wherever it is manufactured, it would need to be ordered quoting the VLT percentage that they require as VLT is the only measure of tint darkness recognized internationally. However, despite this knowledge most tint shops present their films to customers claiming that the darker the tint the higher the percentage, mainly because they are too lazy to correct the customers misunderstanding and would rather just play along. As there is no relation between the random percentages these tint dealers state and the actual darkness of the film according to the technically correct measure of VLT, often a customer ends up with a tint that is illegal according to UAE law.
My advice to UAE customers would be to ask your tint salesman to state the percentage in VLT and once you know this percentage ensure that number is above 30% on the sides and rear windows. In case the salesman does not have a clue about the term VLT, ask him to show you the box of film as specifications are usually listed there. If they are not, it is probably sketchy unbranded tint, from a sketchy unbranded shop – you do not want that stuff on your car anyway.
2) How much heat does tint block?
Although the cars appearance, privacy, fade protection are all relevant factors, heat rejection is the single most important reason why people choose to tint their cars in the UAE.
To understand what determines how much heat your window film will reject, it is important to first understand the components of solar heat energy. Solar heat energy is made up of 3 forms of light – Infrared (IR), Ultra-Violet (UV) and visible light. UV light is measured at wavelength 100 – 380 nm and is a light which we can neither see nor feel, but is the main factor for causing fabrics and furnishings to fade. Visible light is measured at wavelength 380 nm to 750 nm and is the light that enables us to see. Infrared has wavelengths between about 750 nm and 1 mm and is the light which we feel as heat.
Although a small amount of heat is transmitted from both the UV and visible light wavelengths, maximum heat is emitted from near infrared light measured at 900 – 1,000 nm. Therefore, an important specification to note before picking your window film is the amount or IR rejection. Due to recent technological advancements such as nanotechnology, window films are being manufactured with up to 97% Infrared Rejection.
Some film manufacturers have a specification on “solar heat reduction” but as there is no standard method of measuring this, comparing this figure for different film brands is not appropriate.
3) Will tinting my car interfere with my GPS, mobile phone, radio etc.?
Possibly. This depends on the manufacturing and coating process of the window film. Several manufacturers use metals such as nickel, copper, aluminum and silver to coat the polyester film because of their strong heat absorbing/ reflecting properties. However, often the metals reflect away radio waves as well, leading to the common side effect of weak reception for cell phones and broken GPS tracking.
New technologies have enabled window film manufacturers to develop films using non metallic coating methods. Nanotechnology multilayer processes are the most recent of these technologies, as well as the use of ceramic and carbon coating methods. These substances have similar heat rejection properties as metals, but do not share the negative effects of radio signal interference.
4) A tint shop mentioned that I should have the film installed on the exterior of the back window so it does not interfere with the defroster lines. Is this true?
No, window film has no effect on defroster lines and they will continue to function as usual. When low quality window film is installed on the inside of the vehicle the film on the defroster lines tend to peel off first - however, this is only applicable to low quality films. Better quality films come with a strong enough adhesive to withstand heat produced by the defroster.
It is very important to ensure that the film is installed on the inside of the window, as film that is installed on the outside will last for an average duration of 3 to 6 months, especially so in the UAE where the environmental conditions are very harsh. High temperatures, dust and sandstorms would cause the film to peel off and give the windows an extremely unpleasant appearance.
Installation on the exterior tends to be easier, and takes between 5 to 20 minutes, whereas an interior one-piece installation can take up to 1 hour. This is the main reason that the lesser known tint shops tend to install the film on the outside -be sure to insist against this.
5) Will window film stop my upholstery/ leather/ dashboard from fading?
Although window film will not completely stop fading, it will greatly reduce it.
As noted Ultraviolet light is the main cause of fading. UV absorbers are used to stop UV light at the film. The type, amount and location of the absorbers in the product determine the film’s effectiveness in reducing fading. Absorbers located in the adhesive instead of the film itself can be far less stable than those which are built into the film.
Most branded window films have UV absorbers built onto the film, and when the film is professionally installed it should block out 99%+ of UV rays.
NOTE: There have been some updates regarding laws concerning the installation of window film, this article has now been updated to reflect this (06/12/2014).
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