Windshield Cracks: When Can They Be Repaired, and When Do They Need to Be Replaced?

A small crack in the windshield doesn’t necessarily mean you have to replace the entire windshield. But waiting too long can turn a repairable damage into a problem that requires a complete replacement of the windshield. The size of the damage matters, but it isn’t the only factor. Its location, depth, proximity to the edge of the windshield, and the overall condition of the glass can also determine whether a repair is possible. A pebble hits the highway, there’s a soft “tap,” and then a chip appears on the windshield.At first glance, it seems tiny. You tell yourself you’ll deal with it later. The problem? A crack can grow. Road vibrations, stress on the glass, and temperature fluctuations can all contribute to its spread. In Montreal, especially in the winter, a windshield can be exposed to significant temperature swings in a very short period of time. The good news is that windshield damage doesn’t always require replacement. If addressed early enough and conditions permit, a windshield repair can stabilize the damage and preserve the original glass. So, should you repair it or replace it? Here are the main factors to consider.

Can a crack in a windshield be repaired?

Yes. Some cracks and dents can be repaired. However, there is no single rule based solely on the size of the damage. A technician must also take into account its location, depth, shape, and the overall condition of the glass. A small chip in the center of the windshield, for example, is not necessarily comparable to damage of the same size that starts right at the edge.At ADAS Auto Glass, our first priority is to determine whether a windshield repair in Montreal is possible before considering a replacement.When appropriate, the repair typically involves cleaning the damaged area and then injecting a specialized resin into it. The resin is then cured, and the surface is polished. The main goal is to stabilize the damage and limit its spread.However, it’s important to have realistic expectations: repairing a dent does not necessarily mean making it completely invisible. A slight mark may remain visible after the repair.

The 5 Factors That Determine Whether a Windshield Is Repairable

Two types of damage that appear almost identical may require different repairs.Here are the main criteria considered.

1. The size of the chip or crack

This is obviously one of the first things to consider.A small, localized chip generally offers more repair options than a long crack that has already spread across a significant portion of the glass.Size matters, but it must always be considered in conjunction with other factors.

2. The location of the damage

Location can be just as important as size.A chip located in an unobstructed area of the windshield may be a good candidate for repair. The same damage located directly in the driver’s field of vision requires greater caution. Why?Because even after the resin is injected, a slight optical imperfection may remain. In an area critical to visibility, this distortion must be taken into account.

3. A crack that extends to the edge of the windshield

The edge of the glass is an area that is particularly susceptible to stress.When a crack starts at the edge of the windshield or extends to it, its impact on the structural integrity of the glass must be carefully assessed.This situation may lead to a diagnosis that the windshield needs to be replaced, even if the damage appears to be relatively minor.In other words, minor damage doesn’t always mean a minor repair.

4. The extent of the damage

A car windshield consists of several layers.Superficial damage and deeper damage therefore do not offer the same repair options.If multiple layers are affected or if the integrity of the glazing is compromised, simply injecting resin may no longer be appropriate.A photo can provide an initial assessment, but an inspection of the windshield may be necessary to confirm the diagnosis.

5. The number of impacts

A single, isolated chip can sometimes be relatively easy to repair.However, multiple impacts scattered across the same windshield change the assessment.The technician must therefore assess the condition of the entire glazing unit rather than analyzing each impact separately.

Repair or Replace: A Few Real-Life Examples

Here are a few examples to help you better understand the difference.

Situation	Possible Action
A small, isolated chip far from the edge	Repair is often an option
Small, recent crack	Should be inspected promptly; it may still be repairable
A crack that extends to the edge	Replacement may be necessary
A long crack that continues to grow	Replacement is often considered
Visual field defects	A careful evaluation is necessary
Multiple impacts or severely damaged glass	Replacement may be more appropriate

These examples are general guidelines. The diagnosis must always take into account the actual damage, the vehicle, and the condition of the windshield.

Is a crack in a windshield allowed in Quebec?

Au Québec, l’état du pare-brise est également encadré par des normes de sécurité.The Road Vehicle Safety Standards Regulations include, among other things, requirements regarding the condition of the windows and the driver’s visibility.On the portion of the windshield swept by the windshield wipers, the regulations specify criteria regarding intersecting cracks and chips larger than 12 mm in diameter, subject to the exclusions set forth in the regulations.The windshield must also not be damaged to the point of impairing the driver’s visibility.However, it is important to make a distinction: regulatory criteria alone do not determine whether a crack can be repaired.Damage may require repair even if it does not exactly meet one of these criteria. Whether it can be repaired depends, in particular, on its depth, location, shape, and the overall condition of the glass. If in doubt, it’s better to have the damage inspected than to wait for it to spread.

Why can a small crack get bigger?

An impact causes localized damage to the glass.The windshield then continues to be subjected to the normal stresses associated with driving: vibrations, bumps, body movements, and temperature fluctuations.A small crack can then grow.Rapid temperature changes warrant special attention, especially during the Quebec winter.If there is already an impact, avoid, for example, immediately directing extremely hot air onto a very cold windshield. Also avoid pouring very hot water onto the glass to melt the ice. It is impossible to guarantee that a small crack will remain stable for several weeks.The sooner the damage is assessed, the sooner it can be determined whether repairs are still possible before the damage spreads.

Why repair something when it can still be fixed?

When the damage is repairable, the repair allows the current windshield to be kept.Repair is also less invasive than a complete replacement of the glass and generally takes less time.At ADAS Auto Glass, some chips can be repaired quickly, depending on their condition and location.Chez ADAS Auto Glass, certains impacts peuvent être traités rapidement selon leur état et leur emplacement.You can check out our windshield repair service in Montreal to learn more about the repair process, or send us a photo of the damage for an initial assessment.Can’t make it to our shop? Our at-home windshield repair service in Montreal allows us, when conditions permit, to send a technician directly to your home or workplace.

When is it necessary to replace the windshield?

Repair has its limits.When the damage is too extensive, impairs visibility, affects a particularly sensitive area, or compromises the integrity of the glass to a significant degree, windshield replacement in Montreal may be necessary.The technician then removes the damaged glass and installs a windshield that meets the vehicle’s specifications.On newer vehicles, however, the repair may involve more than just replacing the glass.

Windshield with a camera: When should you calibrate the ADAS?

Look in your rearview mirror.Do you see a camera or a housing mounted against the windshield?Your vehicle may be equipped with advanced driver-assistance systems, commonly known as ADAS.These systems can be used, in particular, for certain functions such as lane-keeping assistance, collision warning, and automatic braking.When a camera or other sensor is mounted on the windshield, its positioning must comply with the manufacturer’s specifications.After replacing a windshield on a vehicle equipped with an ADAS camera, the manufacturer’s procedures must therefore be verified.Depending on the vehicle and the system in question, a static, dynamic, or combined ADAS calibration in Montreal may be required to restore the proper settings for the relevant systems.ADAS Auto Glass performs windshield replacement as well as ADAS system recalibration when necessary, thereby handling all stages of the service.

What should you do immediately after an impact on the windshield?

Did a rock just hit your windshield?First, avoid touching the damaged area unnecessarily.Next, try to keep the impact area as clean and dry as possible until it is assessed. Dust, moisture, and other contaminants can seep into the damage and complicate the repair. Also, avoid sudden changes in temperature.Finally, take a clear photo of the impact.At ADAS Auto Glass, you can send a photo of the damage to get an initial assessment of whether a repair is possible.

Have your windshield crack inspected right away

A leak that can be stabilized today may eventually become damage requiring replacement if itADAS Auto Glass has over 30 years of experience in the automotive glass industry and offers windshield repair, replacement, and ADAS calibration services in Montreal, Laval, and on the South Shore.Have you been in an accident and are you trying to decide between repair and replacement?Send us a photo of your windshield or request an estimate. Our team will assess the location and extent of the damage to determine the appropriate course of action. Would you rather know what the costs might be? Check out our guide on the cost of windshield repair or replacement.

FAQ — Windshield Cracks and Repairs

Can a crack in a windshield be repaired?

Yes, some cracks can be repaired. Whether this is possible depends largely on their size, depth, location, and the overall condition of the glass. A quick assessment can help determine the available options before the damage worsens.

Can a crack at the edge of the windshield be repaired?

A crack that extends to the edge requires special attention, as this area is subject to significant stress. Depending on the extent and depth of the damage, replacement may be necessary.

Does a repair make the crack completely invisible?

Not necessarily. The resin is mainly used to stabilize the damage. A slight mark or imperfection may remain visible after the repair.

How long does a windshield repair take?

The time required depends on the type and extent of the damage. Some eligible impacts can be repaired relatively quickly. ADAS Auto Glass also offers a mobile service in Montreal for certain repairs.

Why does a crack in a windshield get bigger in the winter?

Temperature fluctuations create additional stress in the windshield. When an area has already been weakened by an impact, this stress—combined with the vehicle’s vibrations and movements—can contribute to the spread of the crack.

Do you need to recalibrate the ADAS after repairing a small crack?

Not always. It depends, in particular, on the vehicle, the location of the repair, and the manufacturer’s procedures. When a windshield equipped with an ADAS camera is replaced, the procedures applicable to the vehicle must be checked to determine whether calibration is required.

Should I replace my windshield if the crack is in front of the driver?

Not automatically. However, location remains an important factor. A repair may leave a slight visual imperfection; therefore, the technician must determine whether the repair is appropriate and will not impair visibility.

Can I keep driving with a small crack?

A small crack is not necessarily stable. It can spread due to vibrations, stress on the glass, or temperature changes. It is best to have it inspected promptly rather than wait to see if it gets worse.