A rock flies up from the highway and you hear a sharp tap on your windshield. At first, the damage looks small, and you think maybe it’s just a tiny chip or a faint crack. Many drivers ignore it and keep driving.
But days later, the chip spreads across the glass.
This happens often. A small impact from road debris can turn into a long crack after exposure to temperature swings, road vibration, or moisture, and once the crack spreads, repair becomes more difficult and windshield replacement may be required.
The good news is that many chips and small cracks can be repaired quickly if they’re addressed early. A simple windshield chip repair can stop the damage from spreading and restore visibility.
This guide explains how to repair car glass, when a DIY windshield repair kit might work, and when it is safer to visit a professional technician. You’ll also learn how Canadian weather and road conditions affect windshield damage.
With decades of experience in collision and auto glass repair across Western Canada, Craftsman Collision helps drivers repair windshield damage before it becomes a larger problem.
Find a Craftsman Collision location near you for expert auto glass repair.
Why Car Glass Damage Should Be Fixed Quickly
Small windshield damage rarely stays small, and a rock chip windshield repair should happen as soon as possible because several factors cause cracks to grow.
Temperature changes
Windshields expand and contract as temperatures change. In Canada, cold winter mornings followed by a heated defroster can cause cracks to spread quickly.
Road vibration
Every bump in the road places stress on the glass, and over time, vibrations can extend cracks across the windshield.
Moisture intrusion
Rain, snow, or washing the vehicle can introduce moisture into the damaged area, which weakens the glass.
Safety risks
The windshield plays an important role in vehicle safety as it supports the roof structure during rollovers and helps your airbags deploy correctly.
Visibility issues
Cracks in the driver’s line of sight can distort vision and create glare at night.
According to the Insurance Bureau of Canada and Transport Canada, windshield damage is one of the most common vehicle insurance claims in the country, so fixing chips early is often the simplest and least expensive option.
Get a fast quote for windshield repair or replacement today.
Types of Car Glass Damage You Can Repair
Not all windshield damage can be repaired, and some types of cracks require full replacement. Common repairable damage includes:
Bullseye chip
A circular impact point caused by a rock. These are one of the most common forms of windshield chip repair.
Star break
A chip with several short cracks spreading outward from the centre. Many star breaks can still be repaired if caught early.
Combination break
A mix of bullseye and star patterns. These sometimes qualify for repair depending on size.
Damage that usually requires replacement includes:
Long cracks
Cracks longer than about 15 cm (6 inches) often require windshield replacement.
Edge cracks
Cracks that reach the outer edge of the windshield weaken the entire structure.
Multiple impact points
Several chips close together can compromise the glass.
In general, damage smaller than a loonie or shorter than about six inches often qualifies for repair.
Tools and Kits Used to Repair Car Glass
Both DIY kits and professional tools rely on the same principle. Clear resin fills the damaged area and bonds the glass layers together.
Common DIY windshield repair kit components
Most windshield repair kits include:
- Resin injector. A device that pushes repair resin into the chip.
- Adhesive seal. A small ring that creates a seal around the damage.
- Curing strips. Plastic sheets used while the resin hardens.
- UV curing resin. Special adhesive that bonds glass when exposed to sunlight.
- Razor blade scraper. Used to remove hardened resin after curing.
Professional auto glass repair tools
Technicians use more advanced tools to repair windshield cracks which produces clearer results and stronger repairs than DIY windshield repair methods.
- Pressure and vacuum resin injectors to remove trapped air and force resin deeper into the crack.
- UV curing lamps to harden the resin evenly and quickly.
- Precision drilling tools to stop cracks from spreading in certain cases.
Step-by-Step Guide to Repair Car Glass
A DIY windshield chip fix follows a fairly straightforward process as most kits use the same steps.
Step 1: Prepare the windshield
Park the vehicle in the shade and allow the glass to cool. Clean the damaged area using alcohol or glass cleaner to remove dirt and debris.
Step 2: Install the repair tool
Place the adhesive seal over the chip and attach the injector pedestal on top of the seal. This creates a sealed chamber around the damage.
Step 3: Inject resin
Attach the resin syringe and slowly inject repair resin into the chip. The resin fills the small cracks inside the glass layers.
Step 4: Remove air with vacuum
Pull the syringe plunger upward to create a vacuum. This pulls air bubbles out of the crack and allows resin to flow deeper. Leave it for about five to ten minutes.
Step 5: Apply pressure
Push the plunger down to force resin into the damaged area. This step helps make sure the crack fills completely.
Step 6: Cure the resin
Place the curing strip over the repair and expose the windshield to direct sunlight for about fifteen to thirty minutes. The UV light hardens the resin.
Step 7: Scrape excess resin
After curing, remove the plastic strip and use a razor blade to scrape away any extra resin from the surface. The windshield should appear smoother and clearer.
When You Should Not Repair Car Glass Yourself
DIY repairs do not work in every situation, and drivers should seek professional auto glass repair when:
- The crack is longer than six inches
- Damage sits directly in the driver’s line of sight
- The crack reaches the edge of the windshield
- Multiple chips appear close together
- Sensors or cameras sit behind the glass
Lots of modern vehicles have Advanced Driver Assistance Systems (ADAS) and these systems use cameras or sensors mounted behind the windshield.
If the windshield requires replacement, technicians must recalibrate these systems to maintain safety features such as lane-keeping assistance or automatic braking. Attempting a repair in these situations may create safety risks.
How Professional Auto Glass Repair Works
A professional repair process uses specialized equipment to restore the glass as much as possible. The process typically includes:
- Inspection and damage assessment
Technicians examine the size and type of crack to determine if repair is possible.
- Cleaning and moisture removal
The damaged area is cleaned thoroughly to remove dirt or trapped water.
- Precision resin injection
Pressure tools inject resin deep into the glass layers.
- UV curing and polishing
The resin is hardened using UV light and the surface is polished smooth.
- Structural integrity check
Technicians confirm the repair restores strength and visibility.
How Much Windshield Repair Costs in Canada
Auto glass repair costs can vary depending on the size of the damage and vehicle type, but typical price ranges include:
- Chip repair: Usually between $60 and $120 CAD.
- Crack repair: Often between $100 and $200 CAD depending on length.
- Windshield replacement: Usually ranges from $300 to $1,000 or more depending on vehicle technology and sensors.
Many Canadian insurance policies cover windshield chip repair with no deductible, so repairing damage early may cost little or nothing through insurance.
Tips to Prevent Windshield Damage
Windshield damage often happens suddenly, but drivers can reduce the risk. You should always leave distance between your vehicle and gravel trucks as loose stones from construction vehicles often cause rock chips.
It’s also important to avoid sudden temperature changes like pouring hot water on an icy windshield or blasting the defroster immediately, which can stress the glass.
Always try to repair chips immediately, replace older, worn windshield wipers as they can scratch the glass, and avoid parking near construction zones as falling debris and loose gravel increase the risk of impact damage.
If you notice a chip or crack in your windshield, the safest step is to have it inspected by an experienced technician.
Book a professional windshield inspection at your nearest Craftsman Collision location.
FAQs About Car Glass Repair
Can broken car glass be repaired?
Yes, many small chips and short cracks in car glass can be repaired using resin that bonds the glass layers together. Larger cracks usually require windshield replacement.
Can I fix a cracked windshield myself?
You can repair small glass chips with a windshield repair kit if the damage is minor and not in the driver’s line of sight, but larger cracks should be repaired by a professional technician.
What should you do if a rock chips your windshield?
If a rock chips your windshield, try to repair the chip as soon as possible. Cover the chip with clear tape to keep dirt out until the repair is completed.
Can you repair a crack without replacing the windshield?
Yes, you can repair a crack without replacing the windshield if the crack is small and not near the edge of the glass. Cracks longer than about six inches usually require windshield replacement.
