Car windshields are among the most important components in modern vehicles, but how long are they supposed to last? The short and simple answer is that a windshield should last as long as your vehicle does, but seldom is that the case in reality.
There are many factors that can affect the lifespan of your windshield, many of which are within your control while many others are simply beyond your control. How you deal with a cracked or broken windshield, however, is within your control and you should seek to have the windshield repaired or replaced as soon as possible.
What does a windshield do?
A windshield protects the driver and passenger(s) in the event of a collision but it also protects against wind and debris. This may seem obvious, but windshields provide three main benefits to occupants of a vehicle: safety, comfort, and structural integrity.
This last point is important because windshields provide a huge amount of structural integrity for your vehicle in both normal driving conditions and, more importantly during a collision or during a rollover. Indeed, the Auto Glass Safety Council (AGSC) claims that the windshield provides up to 45% cabin structural integrity in the event of a collision and up to 60% in the event of a rollover.
Now, this doesn’t mean that your windshield will survive a collision or a rollover unscathed, but you and your passengers are far more likely to survive if the windshield is performing its primary duties of safety and structural integrity. In all likelihood, collisions and rollovers will lead to a smashed windshield, or at the very least, a cracked windshield.
How windshields are made
Windshields are not made of ordinary glass like you may use for drinking water. For nearly a century now, automobiles in the United States have been using laminated safety glass, a technology invented in 1903 by French chemist Édouard Bénédictus. It took until 1930 for this type of glass to be mandated on all vehicles in Britain and by the early 40s vehicle manufacturers in the United States began adopting laminated safety glass as the standard for all windshields. One important reason for this delay was the fact that most early automobiles didn’t really need a windshield because they typically didn’t achieve as high velocities as today’s vehicles do. In fact, the earliest horseless carriages generally had the driver wearing goggles instead of using a windshield.
Laminated safety glass is different from ordinary household glass and it’s also different from tempered glass, the latter of which is used on car windows and all other non-windshield vehicle glass. Laminated glass consists of two layers of glass sandwiched together with a layer of vinyl (polyvinyl butyral or PVB is typically used) in between. The rapid heating and cooling of the glass creates what appears to be a single, uniform piece of windshield glass with many safety benefits.
Whereas ordinary glass has a tendency to shatter into jagged shards that can be razor-sharp and cause serious injury or death (especially when hurtled towards a vehicle’s occupants at high velocity), laminated safety glass absorbs impacts and is designed to shatter into smaller chunks than ordinary glass. Moreover, the strong structural integrity of a windshield maintains cabin safety during a collision as well as providing the bulk of the vehicle’s integrity during a rollover, which can in turn prevent crushing and entrapment of the occupants.
The most common sources of damage to a windshield
When it comes to the lifespan of your windshield, there are two main things to consider. Firstly, OEM windshields that come with your vehicle off the assembly line today are designed to last as long as your vehicle. The average lifespan of a vehicle (with major variance, of course) is around 10-12 years, so your windshield could remain perfectly intact for about that long.
The second consideration, however, is much more grounded in reality. While some vehicle owners have never had a problem with their windshield, this is probably the exception and not the rule. There are about 15 million windshields replaced every year in the United States, and with over 264 million vehicles on the roads that works out to roughly 6% of all vehicles needing a windshield replacement. As for windshield repairs, it is likely that there are substantially many millions more (if not the majority of auto glass services), so over the course of a vehicle’s lifespan it is highly likely that you may need windshield repair or windshield replacement services.
There are three main reasons why windshields are damaged and they are as follows:
Natural events
The first cause of windshield damage considered comes from natural events such as weather and temperature. Although windshields can sustain high wind forces at high speeds such as when the vehicle is traveling at 50 miles/hour or higher, extreme natural events can be too much for the windshield to handle.
Some examples include:
- Prolonged exposure to UV rays;
- Exposure to rapid changes in temperature;
- Severe weather events, e.g. hurricanes, hailstorms;
- Falling branches from storms.
Physical impact
One of the most common and immediate sources of windshield damage comes from direct physical impact, which can lead to rock chips, cracks, or completely shattering the windshield depending on the severity of the impact.
Some examples include:
- Vehicle collisions and/or rollovers;
- Kicked up rocks and debris from the road;
- Objects deliberately or accidentally thrown towards the windshield;
- Vehicle theft and/or vandalism.
Glass quality & installation
Last but certainly not least, the type of glass used as well as the quality of installation can have a huge impact on the longevity of your windshield. Generally, factory-fitted OEM windshields offer optimal safety and high-quality windshield repairs can meet (or exceed) that level of safety. Replacement windshields should always be high-quality glass fitted by professional auto glass technicians near you.
Some examples include:
- Use of poor quality replacement windshield glass;
- Use of poor quality urethane adhesives for replacement windshield glass;
- Improper application of windshield urethane adhesive product;
- Improper or insufficient application of windshield repair resin product;
- Insufficient safe drive away time or minimum drive away time, leading to poor quality bonding and curing of windshield adhesive;
- Improper windshield fitting and sealing by unskilled auto glass technicians.
The rise of ADAS technology for windshields
In recent years, advanced driver assistance systems (ADAS) have grown from a somewhat rare novelty to the norm for just about all vehicles in the United States. While cruise control dates back over a century in the US, more modern driver assistance technologies such as advanced cruise control, lane departure warnings, blind spot detection and more have revolutionized how we as drivers interface with our vehicles.
All of the safety features offered by ADAS contribute to improving overall driver safety and thus minimize the occurrence of collisions and by extension windshield damage, but this hasn’t put auto glass shops out of business. On the contrary, auto glass shops are thriving now just as before since even with increased driver safety, windshield damage still occurs with ADAS-equipped vehicles.
What has changed, however, is that the cost of windshield replacement has greatly increased for vehicle owners. Not only do ADAS-equipped vehicles need specific (and expensive) replacement windshields equipped with the sensors used to communicate with the vehicle’s onboard computer systems, but the windshield must also be recalibrated whenever it is replaced.
In short and in general, ADAS technology has marginally reduced the demand for windshield replacement by offering superior safety features, but the need for windshield repair and windshield replacement services remains and the latter has significantly increased in cost due to the advanced technologies required to fit and replace an ADAS windshield.
Caring for your windshield and repairing cracks and rock chips
Many of the above causes of windshield damage are simply beyond your control as a driver, but some are fully or partially within your control. Considering the inconvenience of having to have your windshield replaced as well as the cost if you aren’t insured or if your deductible isn’t ideal, it’s usually in your best interest to take reasonable action towards keeping your windshield free from damage.
For adverse weather conditions, consider not driving in extreme weather. If you’re already on the road, try to skip any unnecessary side trips and head directly home or to an enclosed car park. In extreme temperatures, use a sun car shade to reflect sunlight and avoid taking your car directly into or out of a location with extreme differences in temperature, e.g. an air-conditioned garage to/from 100+ degree weather outside. Expansion and contraction can cause extreme stress on a windshield and lead to cracks.
Avoiding physical damage is often far less within your control. Rock chips or cracks could come from ordinary driving no matter how safely you drive. Dirt and gravel roads might kick up a lot more, so try to avoid driving too closely behind another vehicle on these types of roads. To avoid damage from vandalism or burglary, consider parking your vehicle in a more secure area whenever possible. On-street parking in many American cities has become a roll of the dice these days, so try to avoid it unless absolutely necessary.
If your windshield has sustained damage such as a rock chip or a crack, the best course of action is to have it repaired as soon as possible. Most rock chips do not spread but repeated damage can weaken the windshield if left unattended and in some states lead to a traffic violation, especially if your field of vision is obscured. Cracks can often be repaired but are more likely to spread over time. Around 80% of windshield cracks will spread over the next three years, potentially necessitating a costlier replacement at that point.
In terms of cleaning your windshield, only use mild cleaning agents that won’t cause abrasion to the windshield glass. Don’t use ordinary household glass cleaning products and instead purchase a high-quality windshield cleaning solution and use as directed. Take the time to inspect for any cracks or rock chips and check the condition of your windshield wiper blades while you’re at it. Little rocks or debris snagged in the blades could lead to scratches in the windshield.
These tips could help to prolong the lifespan of your windshield by years, but keep in mind that even with the utmost of care and attention your windshield could be damaged anyway from something completely beyond your control.
Repairing a windshield vs replacement
If your windshield does sustain damage at some point (and in all likelihood, it probably will), then your first port of call will likely be to an auto glass shop near you and/or to your insurance provider. It’s important to know which options are available to you, both because it can save you time and money but also because some options may be safer than others and a skilled and experienced auto glass shop should always be committed to safety over profits.
Two of the biggest choices that may be available to you are windshield replacement and windshield repair. Depending on the make and model of your vehicle, the severity and location of the damage, the auto glass technician may be able to repair rock chips or cracks in the windshield instead of replacing it. This tends to be far cheaper and may in some cases be safer whereas in other cases it simply isn’t safe or possible. The big national chains tend to want to push windshield replacement, even if repairs are far better for you, the customer, so try to stick with honest and independent auto glass shops near you rather than the big corporate brands.
With professional windshield repairs, your windshield could last you much longer and you could be saving hundreds upon hundreds of dollars. When windshield repairs are not safe or possible, your only option will be to have the windshield replaced. You may be able to ask for a certain type of glass, however, depending on the make and model of your vehicle. Sometimes, aftermarket glass is just as good as OEM glass and costs a fraction of the price (and it’s often made in the exact same factory but just lacks a stamped logo). Sometimes, aftermarket glass is not your best choice and, quite often, vehicle manufacturers and/or your insurance provider will insist on OEM glass.
Lastly, modern ADAS windshields are a lot tricker to repair due to the embedded sensors needed to maintain the ADAS functionality. ADAS windshields tend to need replacement, which can cost substantially more than replacing an ordinary windshield and they almost always need to be recalibrated, which adds further costs on top.
How long does a windshield last?
By now, you may have already come to the conclusion that there’s no real way of telling how long a windshield will last. OEM windshields that came with your vehicle upon purchase might last as long as the vehicle will, but in all likelihood it will be exposed to rock chips, cracks or severe damage at some random point before then. It could (unfortunately) happen the first day you buy your vehicle or it could happen after 10 years of careful driving or anywhere in between.
While it’s all well and good to care for your vehicle and the windshield, the unpredictability of windshield damage is one reason why it’s important to consider your insurance options for auto glass services and to seek effective and affordable solutions if ever it does happen to you.
Professional auto glass technicians near you across the United States provide a wide range of auto glass repair and replacement services and can help to restore the clarity and safety of your auto glass by providing windshield repair, windshield replacement and ADAS recalibration services for a wide range of vehicle makes and models. myWindshield connects you with reliable, professional auto glass shops in towns and cities across the US.
