MOT Windscreen Rules: If your MOT is coming up and you have noticed a chip or crack in your windscreen, you may be wondering whether it could cause your car to fail.
Your windscreen plays an important role in keeping you safe and giving you a clear view of the road. That is why the MOT test checks the windscreen’s condition, the driver’s view, and whether the wipers and washers work.
If you are unsure whether windscreen damage could affect your MOT, Bridgewater Windscreens can assess it and advise whether a repair or replacement suits your vehicle. The company provides professional windscreen repair and replacement services across Greater Manchester and the wider North West, including convenient mobile services.
MOT Windscreen Rules: What does the MOT check on your windscreen?
During an MOT, the tester checks the windscreen from the driver’s seat. They assess the driver’s field of vision and inspect the glass condition.
The test considers:
- Damage to the windscreen
- Damage within the driver’s field of vision
- The swept area covered by the windscreen wipers
- Excessive tinting or discolouration
- The condition of the glass
- Whether the driver can see their mandatory external mirrors
However, a small amount of damage does not automatically mean your vehicle will fail. The DVSA states that windscreen damage can be an MOT failure when it significantly affects the driver’s view of the road.
How big can a windscreen chip or crack be for an MOT?
The rules depend on where the damage appears on the windscreen.
The area directly in front of the driver is known as Zone A. It sits within the windscreen’s swept area and measures 290mm wide, centred on the steering wheel.
In Zone A, damage measuring more than 10mm in diameter can result in an MOT defect.
For the rest of the windscreen’s swept area, damage measuring more than 40mm in diameter can result in a defect.
This means a chip or crack’s position matters as much as its size. A small area of damage directly in front of the driver can therefore cause more concern than a larger chip elsewhere on the windscreen.
What is Zone A on a windscreen?
Zone A is the section of the windscreen that sits directly in front of the steering wheel.
The area is:
- Within the swept area of the windscreen
- 290mm wide
- Centred on the steering wheel
Because this area sits directly in the driver’s line of sight, the MOT rules are stricter. Damage exceeding the permitted size can affect visibility and result in an MOT failure.
If you have a chip or crack in this area, it is worth having it assessed before your MOT rather than waiting to see whether the tester considers it acceptable.
Can a windscreen chip fail an MOT?
A windscreen chip does not necessarily mean your vehicle will fail its MOT.
If the damage stays within the permitted size and does not significantly affect your view, your vehicle may still pass. However, chips can grow into cracks, particularly when temperature changes, vibration or further impacts put stress on the glass.
For that reason, deal with windscreen damage as soon as you notice it.
A professional windscreen assessment can determine whether the damage is suitable for repair or whether replacement would provide a safer solution.
Can a cracked windscreen fail an MOT?
Yes, a cracked windscreen can cause problems during an MOT.
The tester considers the location, size and effect of the damage on your view of the road. A crack that significantly reduces visibility can result in a major defect. The windscreen must also remain safe and suitable for use.
You should not ignore a crack simply because your MOT is still several weeks away. A small crack can spread and become damage that could have been repaired into damage that requires a full windscreen replacement.
Can a windscreen repair pass an MOT?
A properly completed windscreen repair does not automatically cause an MOT problem.
The DVSA assesses repaired windscreens according to whether the repair interferes with the driver’s vision. When a repair finishes flush with the surrounding glass and does not interfere with visibility, the tester does not count it as damage during the inspection.
This gives you another good reason to have chips and suitable cracks professionally assessed rather than letting them worsen.
What about windscreen wipers and washers?
Your windscreen is not the only part of the visibility system that the MOT checks.
The tester also checks your windscreen wipers and washers. Wipers must work correctly, while defective blades can result in a minor defect. A missing blade or one that clearly fails to clear the windscreen can result in a major defect.
The washers must also provide enough fluid for the wipers to clear the windscreen effectively.
Before your MOT, check that your wipers clear the glass properly and that you have enough screen wash.
What should you do if you have windscreen damage before your MOT?
If you have spotted a chip or crack, don’t wait until the day of your MOT to deal with it.
Instead:
- Check where the damage is located.
- See whether it sits directly in front of the driver.
- Check whether the chip or crack has started to spread.
- Make sure your wipers clear the windscreen effectively.
- Arrange a professional assessment if you are unsure whether the damage needs repairing.
Getting the damage checked early can give you more options. In suitable cases, a windscreen repair may solve the problem. If the damage is too severe or sits in an unsuitable location, you may need a replacement.
Repair or replacement: which do you need?
There isn’t a single answer for every damaged windscreen. The right solution depends on the size, location and type of damage.
A professional windscreen technician can assess the glass and advise whether you need a repair or a replacement.
At Bridgewater Windscreens, having your windscreen checked before your MOT can help you deal with damage before it becomes a bigger problem.
MOT Windscreen Rules: Don’t let windscreen damage catch you out at your MOT
A small chip might not seem serious, but its location and size can affect whether it meets MOT Windscreen Rules. Damage within the driver’s main field of vision has stricter limits, whereas larger damage elsewhere can cause an issue in the swept area.
If your MOT is approaching and you have a chip, crack or other windscreen damage, get it assessed sooner rather than later.
Bridgewater Windscreens can help you determine whether your windscreen needs repair or replacement, helping you prepare your vehicle for its MOT and get safely back on the road.