Common Windscreen Cracks & Chips
The way windscreens are manufactured and the types of hazards they are exposed to daily results in a few common types of cracks and chips. And this is good because it allows Instant Windscreen’s auto glass technicians – and you – to easily assess whether a windscreen can be repaired or needs to be replaced. However, knowing that your damaged windscreen can be repaired shouldn’t encourage you to put the repairs off for as long as possible because all you’re really doing is giving the crack or chip time to grow to a point where it can no longer be repaired. Being able to tell whether a chip or crack can be repaired or calls for the windscreen to be replaced merely helps you schedule enough free time for the work.
And if finding enough free time seems unlikely, remember we do also offer a 24-hour mobile repair and replacement service, with one of our skilled technicians coming to you to sort out your auto glass woes. Which brings us to our guide on identifying the different types of cracks and chips, and how to tell whether they can be repair or not. Two key factors that influence whether any damage can be repaired or not is the size and depth, along with where it is located. The critical vision area (CVA) is a section of your windscreen directly in front of the steering wheel. It is at least 300mm wide, or the width of your steering wheel, and extends from the top of the windscreen to the bottom.
A chip that is mostly round and can almost resemble a target – or bullseye – with concentric circles or rings around it. If located within the CVA, a bullseye chips cannot be larger than 10mm, with a maximum size of 20mm allowed anywhere else on the windscreen.
Also mostly round, but unlike a bullseye chip, a crater is much deeper. Because of that it cannot be larger than 5mm if outside the CVA, and only 2mm if in the CVA
A star shaped crack/chip: the size of the actual chip is quite small, but with a burst of cracks extending outwards from the chip. Including the cracks, a star chip cannot have a diameter of more than 30mm anywhere on your windscreen, but half that if located inside the CVA.
Sometimes called a half-moon chip, this is a crescent or half circle chip that cannot be wider than 15mm if occurring within the CVA, and 25mm if elsewhere on the windscreen.
Exactly what the name suggests, cracks cannot be longer than 25mm when found within the CVA, and no longer than 100mm elsewhere on your windscreen. However, if a crack starts or ends on the edge of the windscreen it cannot be repaired.
Other Factors That Affect the Repairability
Size and location are the main factors that determine whether a chip or crack can be repaired or call for the windscreen to be replaced. But there are a few other conditions our technicians will look for before proceeding:
- The number of past repairs – if our technicians are able to see evidence of eight or more past repairs to the windscreen, they will not be able to carry out any new repairs. However, if any number of past repairs were fully or partially within the CVA they will also not be able to carry out new repairs.
- The depth of the damage – windscreens consist of two layers of glass bonded together by a layer of laminate. If the crack or chip extends right through the top layer of glass it cannot be repaired. Additionally, if there is any sign of delamination close to where the chip or crack is located, the possibility of repair is ruled out.