A cracked windshield looks like a cosmetic problem, and that is why so many people drive on one for months. It is not cosmetic. The windshield is a structural part of the car, the crack is getting longer whether you can see it or not, and in Ontario a crack in the wrong place is a ticketable offence. Here is what is actually going on.
What the windshield does besides keep the wind out
On a modern unibody car, the bonded windshield contributes a meaningful share of the roof's crush resistance in a rollover, and it is what the passenger airbag pushes against when it deploys. Both of those depend on the glass being intact and properly bonded to the frame. A crack is a line along which the laminate has already failed. In a rollover or a collision, a cracked windshield is more likely to let go, and a windshield that lets go means an airbag that deploys into open air.
That is the worst case, and it is rare. The everyday problem is visibility. A crack refracts light. At night, oncoming headlights turn it into a bright line across your field of view; in low winter sun it does the same thing in daytime. That is the reason the law cares about where the crack is.
When a cracked windshield is illegal in Ontario
Ontario's Highway Traffic Act does not set a crack length. It prohibits driving with a windshield that obstructs the driver's clear view of the road. In practice, police apply that to cracks in the area swept by the driver's side wiper, and to spidered or heavily cracked glass anywhere. A small chip in the passenger corner will not get you stopped; a crack across the driver's line of sight can, and it will fail a Safety Standards Certificate inspection if you sell or re-register the car. Our post on whether you can get a ticket for a cracked windshield covers the specifics.
How fast a crack spreads in Ottawa
Faster than almost anywhere else in the country, for one reason: temperature swings. Laminated glass expands and contracts with heat. A car that spends the night at -20°C, then gets a blast of defroster on the inside of the glass at 7 a.m., puts the windshield through a stress cycle every single morning. Add a pothole on the Queensway and the crack runs. A chip that was repairable in November is routinely a 40-centimetre crack by February.
The practical rule: if you can see it, deal with it this week. Chips and short cracks that start away from the edge of the glass can usually be repaired in about 30 minutes, often with no deductible. Once a crack reaches the edge, the only option is replacement.
Repair or replace: the quick test
- Smaller than a toonie, not at the edge, not in front of a camera: repair.
- Short crack, a few centimetres, starting away from the edge: usually repair.
- Crack reaches the edge, or is longer than a business card: replace.
- Damage in front of the forward camera or rain sensor: replace, and recalibrate.
- Two or more cracks, or a spidered impact point: replace.
Will insurance cover it?
If your Ontario policy carries comprehensive coverage, glass is covered. Many insurers waive the deductible for a repair, because a repair costs them a fraction of a replacement. Delaying can work against you: if a repairable chip becomes an unrepairable crack, the claim goes from a small repair to a full replacement plus, on newer cars, ADAS recalibration. How the claim works.
The short answer
Can you drive with a cracked windshield? Physically, yes. Should you? Not for long. A crack outside the driver's view is a repair you should book this week. A crack in the driver's view is a ticket risk and a replacement. Either way, the cheapest and safest moment to deal with it is now.
Common questions
Can I drive with a small crack in my windshield?
You can, but a small crack becomes a long one quickly in Ottawa winters, and once it reaches the edge of the glass it can no longer be repaired. Book a repair the week you notice it.
Does a cracked windshield affect airbag deployment?
It can. The passenger airbag deploys against the windshield, and a cracked windshield is more likely to let go under that load.
Is a cracked windshield illegal in Ontario?
It is illegal if it obstructs the driver's clear view. A crack in the driver's wiper sweep is the usual trigger for a ticket.
Related
Can You Get a Ticket for a Cracked Windshield in Ontario?
Ontario does not set a crack length. It sets a visibility standard, and police apply it to the driver's side of the glass. Here is where the line is and what it costs to cross it.
How Big a Crack Can Be Repaired on a Windshield?
Size matters less than location and age. Here are the actual limits we work to, the damage types that repair well, and the ones that do not.
Does Insurance Cover Windshield Replacement in Ontario?
Usually yes, if you carry comprehensive. Here is what that means, what the deductible looks like, why chip repairs are often free, and the one right most drivers do not know they have.