What are windscreens made of?
Windscreens are made from laminated glass, where layers of glass are placed on top of each other with a plastic sheet between them.
When the windscreen breaks, the glass sticks to the plastic sheet, preventing the broken pieces from flying inside the car. As windscreens don’t always break completely, some cracks and damage can be repaired - but there are limitations.
What can and can't be repaired?
Whether your windscreen can be repaired depends on where the crack is.
Your window is divided into two sections – one section is the Critical Vision Area (CVA), which is in line with the centre of the driver’s headrest and extends 150mm either side, to 90mm from the top of the windscreen and 65mm from the bottom. The rest of the windscreen outside that area is called Outside the CVA.
The size of the crack and its location determines whether it can be repaired.
Your windscreen cannot be repaired if:
- A crack starts and finishes at the edge of the windscreen
- The damage affects more than the outer layer of glass
- The windscreen bonding layer has deteriorated
- There are eight or more repairs on the windscreen
- There is a previously repaired crack over 100mm
- Two or more previous repairs are in the Critical Vision Area (CVA) and the new damage is in the CVA
- An adjacent previous repair is in the overlay area (the overlay is a tool used to assess damage to windscreens) and the new damage or previous repair is in the CVA
This is in line with the Australian/New Zealand standard for windscreen repairs (AS/NZ 2366:1999).
Window tinting
Window tinting protects the interior of your car from harmful UV rays and keeps the inside temperature down.
The front windscreen may have a tinted band at the top providing it does not exceed more than 10 per cent of the windscreen depth and is above the sweep of the wipers.
The general rule is that the tint should not be darker than 35 per cent visible light transmission (VLT). This means that 35 per cent of available light passes through the window. For the rear windows of a car, the Department of Transport will allow a minimum of 20 per cent VLT tint to be applied.
Tinting must not be mirror-like, as this can be a hazard to other road users.
Sun shields
Side window sun shields protect your car's interior and passengers from the sun.
There are many types available – some shields stick to the window and others fit like a sock. Make sure they do not block your visibility, as anything that impedes the driver's vision is illegal.
