Car windscreen repair and replacement: what are your options for cracks and chips?

Dealing with a chipped or cracked windscreen can sound like a hassle, but prompt attention is key to preventing further damage and keeping a clear view of the road ahead. Depending on the severity of the damage, a cracked windscreen could result in a failed MoT or even penalty points and a fine if you’re stopped by the police, so it's always worth investigating as soon as possible.

Whether you opt for a DIY repair, professional help, or need a full replacement, understanding your options will help you make the best decision for your windscreen damage. And remember, a clear view of the road is not just about comfort – it’s a critical part of safe driving.

So, what are your options when your windscreen is chipped or cracked? Here’s what you need to know.

Assessing the damage

The first step in dealing with a chipped or cracked windscreen is to assess the damage. Not all chips and cracks are created equal, and the extent of the damage will determine whether it can be repaired or if you need a full replacement.

Chipped windscreen 

Chips are the most common type of windscreen damage. They’re caused by small stones or debris hitting the windscreen and chipping away a small piece of glass. They can vary in size and shape, but they are generally smaller than a £2 coin. 

It can sometimes be difficult to spot a small windscreen chip, particularly if it’s out of the driver’s sightline, but it’s important to have it repaired as soon as possible. A chip can unexpectedly turn into a larger crack, which will most likely be impossible to repair. 

A chip larger than 10mm in diameter within the driver’s line of sight (known as the ‘A-zone’) will result in an MoT failure. If the chip is larger than 40mm, the car will fail its MoT regardless of the location of the chip.

Cracked windscreen

Cracks are longer lines that spread across the windscreen. They can range from a few centimetres to spanning the entire width of the glass. Cracks typically start from the edge of the windscreen or from an existing chip that has been neglected.

A crack in your windscreen is more likely to impede your view than a chip. That’s important, as the police can stop you if they deem your windscreen to be unsafe, potentially resulting in a fine and penalty points on your licence.

Again, if the crack is larger than 10mm and within the driver’s line of sight, or if it’s larger than 40mm elsewhere, the car will fail its MoT. 

When can you repair a windscreen?

Not every chip or crack means an automatic windscreen replacement. Most small chips can be repaired if they meet certain criteria.

If the chip is smaller than a £2 coin – roughly 25mm in diameter – it can probably be repaired, so long as it’s outside of the driver’s line of sight (known as the ‘A-zone’). If it’s within the driver’s line of sight, then it probably can’t be repaired if it’s larger than 10mm in diameter.

Cracks generally can’t be repaired, unless they’re very small. A crack reduces the structural integrity of the windscreen and is more likely to spread, further impeding the driver’s view of the road.

If a chip or crack is very close to the edge of the windscreen (within 70mm), then it probably can’t be repaired, either. In this position, the damage is likely to have weakened the structural integrity of the windscreen. Some modern cars also feature forward-facing cameras or sensors behind the rear-view mirror. If the glass is cracked in this position, some companies won’t be able to repair the damage.

A professional will be able to provide an accurate analysis of your windscreen damage. If you’re unsure whether your windscreen can be repaired or if you need a replacement, it’s best to ask an expert for advice.

How to repair a windscreen: DIY or professional?

There are several DIY windscreen repair kits available that can be a quick fix for minor chips. These kits usually include a resin to fill the chip or crack and a curing strip. While DIY kits can be convenient and affordable, they are often not as effective as a professional repair. If you’re not confident or if the damage is significant, it’s better to seek professional help.

Professional windscreen repair technicians use high-quality resin and specialised equipment to fix chips and cracks. The process typically involves:

• Cleaning and removing any debris from the damaged area.
• Injecting resin to fill the chip or crack.
• Curing the resin using UV light to harden the resin.
• Polishing and smoothing the area to ensure a clear, distortion-free finish.

Professional repairs are generally quick, often taking less than 30 minutes, and many insurance policies will cover the cost.

How much does a windscreen repair cost?

The cost of windscreen repair or replacement can vary widely depending on several factors, including the make and model of your car and the extent of the damage. It will also depend on your insurance – not every policy will cover windscreen repair or replacement.

A windscreen repair for a chip will typically cost anywhere from £40 to £100, depending on the severity of the damage. A replacement is likely to be much more expensive, particularly if you own an uncommon vehicle. 

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