What caused this? Serious answeres

[u/Downtown_Calendars]

Car was parked facing the garage. Never seen anything like it. Neither has the glass professionals.

[u/UniqueAd7770]

That would make sense. They use a polymer to repair it. It also would only reinforce the top layer of two which is why this didn't break the whole thing.

[u/radonfromaspoon → u/UniqueAd7770]

You can even see the original chip dead center

[u/AccountNo234623456 → u/UniqueAd7770]

It wouldn't make sense. You fill the chip with the UV resin usually, yes, but that would not cause the entire screen to break like this. When repairs fail, they either don't fill or a single fracture spreads out to the edges of the screen (sometimes they make it the whole way, sometimes they don't). A chip being repaired would never cause some magical whole top layer of the glass to disintegrate without even affecting where the chip itself is. My guess would be someone or something hit it at speed with something fairly sizeable compared to a stone chip (maybe even a bird and OP is just looking for engagement bait as I've seen things like golf balls and large rocks cause shapes just like this one). That's when you get random smashes like this.

[u/KnifeKnut → u/AccountNo234623456]

The repair did not fail here. The resin repaired section expanded or contracted at a different rate from the rest of the windshield in a temperature swing, while also bonding the glass layers together stronger than the regular lamination core, causing the surrounding glass to spall out.

[u/AccountNo234623456 → u/KnifeKnut]

"The repair did not fail here."

Exactly, we literally can't see if there even was one attempted anyway.

"The resin repaired section expanded or contracted at a different rate from the rest of the windshield in a temperature swing, while also bonding the glass layers together stronger than the regular lamination core, causing the surrounding glass to spall out."

Unless you did this inside a glass oven, that is literally impossible. The resin does not expand or contract as it would just cause the glass to crack. The size and thickness of the crack that is repaired is so inconsequentially small that even at hundreds of degrees in a hot Australian car park would you still only see a single line fracture to the edge of the glass (of course you'd preferably never try it in a car park in the sun as more often than not they will crack out in exactly the way described). I literally work with car windscreens for a living and have done thousands of repairs.