The claim

Tint film manufacturers claim that:

  • it improves appearance
  • reduces interior temperatures
  • reduces the entry of infra red (IR) and ultra violet (UV) radiation
  • aids privacy
  • reduces glare, and
  • for some types of film, increases security

The facts

 However, tinting also has some downsides.
  • Reduced light transmittance also reduces visibility in low light conditions making it harder for the driver to see pedestrians and cyclists
  • This reduced visibility can make manoeuvring and reversing more difficult
  • Road users, such as cyclists and motor cyclists, claim they cannot see through the car windows in order to assess on-coming traffic or gauge the intentions of the driver

While tint films claim to block significant portions of both UV radiation, (both UVA and UVB can contribute to skin damage and skin cancer) and IR radiation (that heats the vehicle’s interior), a fact that is often overlooked is that automotive glass also blocks a significant amount of UV and a reasonable amount of IR radiation.

Information from the Cancer Council indicates that ordinary automotive glass filters out:

  • about 97 percent of UVB, and
  • 37 percent of UVA radiation
  • while laminated glass (used in windscreens and some side windows) blocks all UVB and about 80 percent of UVA.

RACQ tests have shown that:

  • while tint films slow the uptake of heat through the windows, they also slow the loss of heat
  • the heat rise and loss with film present are both slower, but the interior temperature reaches the same point as it would without film - and stays there longer after the heat source has been removed
  • glass is only one of the heat transfer paths into a vehicle, film has no effect on reducing heat transfer through the metal body structure
For information on the effects of window tinting on cabin temperatures see pages 16 to 21 of the RACQ Temperatures in Cars Survey (PDF, 2.1MB).

The Law

Queensland’s Department of Transport and Main Roads regulations allow the use of tinting film:

For vehicles with Non-tinted Glass

  • Window tinting, other than the front windscreen, must have a light transmittance factor of no less than 35% (T35) on the driver’s and passenger front windows.
  • Provided the vehicle has a rear vision mirror on each side, it may have window tint of not less than 20% (T20) light transmittance behind the driver's seating position.
  • A goods vehicle may have a luminous transmittance of 0% or more provided the vehicle has a rear vision mirror on each side.

For vehicles with Factory-tinted Glass

  • Film may be applied to factory tinted windows, but when these films are applied to tinted glass, the combination of tints must still allow a minimum light transmittance of 35 per cent (T35) on the driver’s and passenger front windows and 20% (T20) on the rear windows.
  • A goods vehicle may have a luminous transmittance of 0% or more provided the vehicle has a rear vision mirror on each side.

For windscreens

  • Windscreens can be manufactured from tinted glass provided they have a light transmittance of at least 70 percent for vehicles built before 1971 and 75 percent for later models, but they cannot be tinted using film
  • the exception is a band across the top of the windscreen no lower than a line drawn horizontally across the windscreen at the uppermost points of the vehicles original wiper blade travel, or no more than 10 percent of the windscreen’s area, whichever is the lesser

Privacy glass

Many vehicles now offer what is known as ‘privacy glass’ for windows behind the driver. This is very dark and is acceptable only if it meets the requirements of the relevant Australian Design Rules and is provided as original equipment by the vehicle manufacturer.  Tint film cannot be fitted to privacy glass if it results in a light transmittance of less the 20 percent (T20).

Choosing a tint film

When choosing tint film look for one that:

  • meets all legal requirements
  • blocks the most UV and IR radiation (this is not necessarily related to the darkness of the tint)
  • is clear or at least the lightest shade available to minimise the reduction in visibility.

Other points

  • For the purposes of vehicle roadworthiness, tint films must comply with the requirements outlined above and be free of wrinkles, bubbles, discolouration and scratches that would impair visibility through the glass and film
  • Some metallised tint films can affect the operation of in-glass radio aerials and e-toll transponders

Note: There is some variation in the tinting regulations between States and Territories.

For more information consult the Department of Transport and Main Roads (DTMR).