Is it legal to drive with a cracked windscreen?

Driving with a cracked windscreen in the UK is a complicated issue but depending on the size and location of the chip, you may be able to repair it and continue driving legally. Cracked windscreen law is designed to keep everyone safe, so in looking up the law regarding your cracked windscreen you are doing the right thing. So, is it legal to drive with a cracked windscreen? Let’s find out.

Implications of a cracked windscreen

A cracked windscreen may seem benign at first but the safest option is to have the windscreen repaired or replaced as soon as you notice the crack. This is for many reasons to do with safety.

Firstly, any blemish in the windscreen transparency will catch the eye of the driver and distract them. This is particularly true during the summer months when high visibility, strong sunlight and the chances of your car being freshly washed are high.

Secondly, small cracks quickly grow to become large cracks. This is caused by the shocks that radiate through the windscreen as the vehicle travels over bumps and potholes in the road. As a crack gets larger, it becomes less and less safe as it compromises the strength of the windscreen.

Finally, cracked windscreens present additional problems when airbags are deployed during an accident.

Cracked windscreens and MOTs

For MOT testing purposes, the windscreen of every vehicle is split into ‘zones’. These zones, from zone A to zone D, are used to prioritise the driver’s line of vision through the windscreen.

Zone A is directly in front of the driver with B sitting either side in the peripheries. Further towards the passenger side is zone C and, finally, zone D occupies the upper corner on the passenger side.

The relationship between windscreen cracks and MOTs is defined along these lines and here is a summary of what to expect:

  • A crack or chip of 10 mm or more in zone A is cause for MOT failure
  • A crack or chip of 40 mm or more in any zone of the windscreen is cause for MOT failure
  • If a repair has been carried out and has either a.) reduced the size of the crack or chip to an acceptable size or b.) completely repaired the blemish, this will not cause MOT failure

Windscreen zones

Windscreen zones A-D are set in order of priority for the driver.

windscreen zones

Zone A is officially a 290 mm vertical strip of the windscreen. The strip is centred using the steering wheel.

Zone B is in the peripheries of zone A, often split into two distinct sections.

Zone C occupies most of the windscreen directly in front of the passenger seat. This zone is still important in terms of the driver’s line of sight.

Zone D describes the remaining part of the windscreen. This is often the top corner of the passenger’s side and is of least importance for the driver’s line of sight.

Windscreen laws in the UK

The highway code states that a driver’s vision shouldn’t be impeded in any way. This includes cracks and chips, as well as snow and ice. If your car is pulled over and a crack or chip is significantly affecting your vision, it can be grounds to charge you with an offence. The penalty for this offence is typically 3 points on your driving license for driving an unroadworthy vehicle.

Motorway Windscreens provide fast, reliable windscreen repairs and replacements throughout Leeds, Grimsby, Sheffield, Doncaster, Chesterfield, Barnsley and many locations throughout the UK. We pride ourselves on our prompt response, quality workmanship and excellent customer service, so you can have peace of mind knowing that you are in the hands of experts when coming to us. Contact us today to book your windscreen repair or replacement.