Auto Glass
Every January, our phone rings constantly. Customers describe the same scenario: they had a small chip that "wasn't bothering anyone" all summer, then they walked out to the car one morning and there was a foot-long crack stretched across the windshield.
It's not bad luck. It's physics.
The physics
A windshield is a sandwich — two layers of tempered glass bonded around a thin sheet of plastic (PVB). Glass expands when warm and contracts when cold. When one part of the windshield is at a different temperature than another, the warm section is trying to grow while the cold section is staying put. The stress concentrates at any weak point — and the weakest point on a chipped windshield is, of course, the chip.
The four scenarios that destroy chipped windshields
- Defroster on full blast against a cold windshield — huge localized temperature differential, cracks travel toward the vent.
- Hot water on an iced-over windshield — one of the fastest ways to crack even an undamaged windshield.
- Slamming the doors — cabin pressure spikes flex the glass.
- Overnight temperature plunges — even with no driving, a chip can grow because the whole windshield contracted.
What to do instead
- Warm the cabin gradually — defroster on low for 5–10 minutes.
- Scrape physically — gentler on damaged glass than thermal shock.
- Garage the car if possible.
- Repair the chip before winter, not during.
If your chip has already become a crack longer than six inches, repair is no longer structurally sound. Book a windshield replacement — we direct-bill major insurers and handle ADAS calibration in-house.