I have a windshield crack on a new vehicle that I originally thought was a stress crack, since it appears to originate at the edge and move toward the center, and I did not ever notice any impacts occur. However, when looking closely I see at one point in the "fault line" a pattern that could maybe be argued is an impact site. I guess the real question is: could something like this develop in the middle of a stress crack, or does the existence of this pattern mean it is undeniably an impact crack? I realize photos can only convey so much, so hopefully they are helpful. I took two photos, in the first one the windshield is still dirty, but I think the crack is focused better there. Thanks!

enter image description here

1 Answer 1


I cannot tell you with 100% surety this was caused by an impact, but I'd suggest it probably was. Glass is a strange beast. It does have some flexibility to it, but if you get a stress riser in it, a crack can form. A rock impact creates a HUGE stress riser in the glass and the crack runs from there.

If you'd like to know more about stress risers, you can read this Q&A I wrote.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.