How Windshields Are Replaced: Step-by-Step Guide for Every Generation

A damaged windshield is more than just a nuisance—it’s a safety risk and, in California, it can also put you on the wrong side of the law. Whether your glass has a small crack or a major break, knowing how windshields are replaced helps you understand what to expect, your legal rights, and the steps professionals must follow to ensure your car is safe to drive again.

In this blog, we’ll walk you through the replacement process, the laws in California, insurance considerations, and the technology involved.

Why Windshield Replacement Matters

Your windshield isn’t just a piece of glass. It is an integral safety component of your car that:

• Provides structural integrity to the vehicle’s cabin
  
  
• Supports proper airbag deployment
  
  
• Houses modern sensors and cameras for driver-assist systems
  
  
• Protects you from debris, wind, and weather
  
  

Because of these safety functions, both California state laws and federal standards regulate how a windshield must be replaced.

The Step-by-Step Process of Windshield Replacement

Professional installers in California follow a detailed procedure to meet both safety standards and legal requirements. Here’s how windshields are replaced the right way:

1. Pre-Inspection and Preparation

The technician inspects the damage, confirms the right replacement glass (including features like rain sensors or heads-up display), and documents pre-existing vehicle conditions. Sensitive electronics are scanned and protected before the work begins.

2. Removal of the Old Windshield

Trim pieces, wipers, and moldings are removed. The old urethane adhesive is carefully cut away so the windshield can be lifted out without damaging the vehicle frame.

3. Treating the Pinchweld

The metal frame where the windshield sits—called the pinchweld—is cleaned and treated. Any scratches or exposed metal must be primed to prevent corrosion.

4. Applying Adhesive

A specialized automotive urethane adhesive is applied in a precise bead. This adhesive is what bonds the new windshield to the car and must meet FMVSS 212 crash-retention standards.

5. Installing the New Windshield

The new windshield is set in place using vacuum cups and alignment tools. The glass must be perfectly centered to prevent leaks, wind noise, or ADAS issues.

6. Reconnecting Sensors and Calibrating ADAS

Many modern vehicles have cameras and sensors mounted on the windshield that support lane departure warning, adaptive cruise control, and emergency braking. After replacement, these systems need calibration. In California, the Bureau of Automotive Repair (BAR) requires that shops disclose these calibrations on your estimate and invoice. Learn more about ADAS calibration from NHTSA.

7. Safe Drive-Away Time (SDAT)

The adhesive requires time to cure before the car can be safely driven. This “safe drive-away time” must be disclosed to the customer. Driving too early can compromise windshield retention in an accident.

California Laws You Should Know

California’s Vehicle Code Section 26710 makes it illegal to drive with a windshield that has cracks or defects impairing the driver’s vision. If cited, you may be required to repair or replace it within 48 hours.

Other laws include:

• Vehicle Code Section 26708 – Prohibits tinting or placing materials on the windshield that block visibility, except in limited cases.
  
  
• Insurance Code Section 758.5 – Prevents insurance companies from forcing you to use a particular repair shop. You have the right to choose where your windshield is replaced.
  
  
• Environmental Regulations – In regions like Los Angeles, adhesives must comply with strict air quality rules limiting VOC emissions.
  
  

Insurance and Cost Considerations

In California, windshield replacement is generally covered under comprehensive insurance. However, unlike some states, California does not require insurance companies to offer zero-deductible glass coverage. Some insurers do provide optional “full glass coverage,” which reduces or eliminates your out-of-pocket costs.

Always confirm with your insurer:

• What type of glass is covered (OEM vs aftermarket)
  
  
• Whether calibration costs are included
  
  
• If you can choose your own repair shop (legally, you can)
  
  

For more details, you can explore consumer resources at the California Department of Insurance.

Why ADAS Calibration Matters After Windshield Replacement

If your car is newer than 2016, chances are it has at least one ADAS feature. A misaligned camera or sensor can cause your safety systems to fail, even if your new windshield looks perfect. This is why calibration is a mandatory step in proper windshield replacement.

Shops must perform either static calibration (in-shop with targets) or dynamic calibration (road test using specialized equipment). Sometimes both are required. Always ask for a calibration report after the job.

Key Takeaways

• The process of how windshields are replaced involves careful removal, proper adhesive use, and sensor recalibration.
  
  
• California law requires that windshields be free of vision-impairing damage and compliant with tinting restrictions.
  
  
• Insurance may cover the cost, but deductibles and coverage vary.
  
  
• You always have the right to choose your repair shop, not just the one your insurer recommends.
  
  
• Modern cars almost always require ADAS calibration after windshield replacement.
  
  

Final Thoughts

A windshield replacement in California isn’t just about swapping glass. It’s a regulated process that combines safety standards, legal compliance, and modern vehicle technology. Understanding how windshields are replaced ensures you know what questions to ask and how to protect your rights.

If you’re dealing with a cracked or damaged windshield, make sure the shop follows OEM and Auto Glass Safety Council AGRSS standards, provides you with full paperwork, and completes all necessary calibrations.

By knowing the process and the laws, you can make sure your car is both road legal and safe for you and your passengers.

📍 Locations:

San Jose Office: 3851 Charter Park Drive, Suite L, San Jose CA 95136

Santa Clara Office: 1250 Norman Ave, Santa Clara CA 95054

📞 Phone: +1 408-564-0419

🕒 Hours: Monday to Friday- 8am to 5pm | Saturday & Sunday- Closed