How is a Windshield Replaced?

Without a doubt, the windshield is the primary safety restraint in a car. So, replacing it is a task that has to be thoroughly addressed no matter what. Unfortunately, many car owners default to lower-cost options to save money. However, this puts them in jeopardy, especially after a serious accident that may even cost them their life.

Importance of Correct Windshield Replacement

Automobile glazier adding glue on windscreen or windshield of a car in auto service station garage before installation

For more reasons than one, it is imperative to have your windshield correctly installed. In any other case, the windshield will not provide the necessary support in an accident and allow the roof of the car to collapse on its occupants in the instance of a roll-over accident. That aside, the windshield plays another protective role as it acts as a barrier between the outside of the car and the airbag. With an improperly installed windshield the airbag, which exerts a huge force on the windshield, will pop out of the vehicle and lose its efficiency in protecting you. Plus, if one just slams a windshield into a vehicle and pretends that everything is okay, chances are the car owner will soon need to face leaks and rusting issues. It has become apparent that your windshield replacement is not the best time to start cutting corners.

Replacing your Car’s Windshield Yourself

That being said, and provided you (if you are installing the windshield yourself) or expert installers are using original manufacturer’s glass and the proper adhesives (see below), here is a step-by-step windshield replacement guide.

  1. Detach the wipers, rear view mirrors and all other items attached to the windshield (or near it).

  2. Protect the vents (defroster and heater) by covering them with a towel or paper.

  3. Use gloves to avoid the grease from your bare hands to mix with the adhesives and bonding agents and prevent them from bonding correctly. Wearing gloves also protects you from getting cut.

  4. Insert a knife at the rubber gasket around the window and carefully slit a corner. If you notice that it is damaged (the gasket), you will also need to replace that one, too.

  5. Use a screwdriver (the thinnest you can get your hands on) to separate the gasket from the glass. To do that, insert it into the slit and carefully run it around the frame of the windshield.

  6. Remove the gasket and gently push the glass from the inside out. This will allow you to separate the glass from the frame and remove the windshield. Be prepared, though, when you do so, because the glass will be heavy. The safest way to deal with this is to get an extra pair of hands to help you out so you are certain the glass won’t shatter or break at any point of the process.

    Get rid of all bits and pieces of broken glasss

  7. Clean the frame properly. If there is any rust, make sure you also address that issue and get rid of it.

  8. Time to frame the new windshield with the gasket. Ensure that you have not placed the outside of the gasket on the inside of the glass or the opposite.

  9. The selection of the right bonding agent is paramount to the proper installation of the windshield. It should definitely be the same (or have the same bond strength) as the one approved for the original installation (i.e. resin-based or urethane adhesive). Butyl and silicone are sealants used in the past that only hold 60lbs/sq.inch, so stay away from them. The same goes for bathtub caulking; unless you want to see them pull apart in an emergency traffic situation. Urethane adhesive is widely used now and is 10 times stronger than others (holds 600lbs/sq. inch).* And, don’t forget to use a primer, too.

  10. Apply the bonding agent to the outer edge of the gasket. Then, slowly place the windshield on the frame. Press it firmly into place. If all goes well, it should have a tight fit with the gasket, and the molding will be straight.

  11. With a cloth or towel, remove excess adhesive or bonding agent from both outside and inside the car.

  12. Wait, at least, an hour before you get behind the wheel. And, just to be safe, experts say it is best to let the car sit for a good 12 hours before you drive it.

* You may be recommended a replacement adhesive to lower the cost. Please refrain from using it as chances are it will not have passed the Federal Motor Vehicle Safety Standards testing. Or, it could have passed the FMVSS 216 roof crush test (roll-over protection) and failed to pass the FMVSS 212 windshield retention test (or vice versa).

Tips to Save you Money & Ensure an Excellent Driving Experience:

  • Have a damaged windshield repaired the soonest possible (if the damage is repairable). Stars and rock chips, even large cracks (if they intersect with only one edge of the windshield), can be repaired much easier if fresh. This saves you the cost of having to buy a new windshield. If you leave a crack unattended for long, rain will wash dirt into it, and it will be more difficult to seal. So, always keep some clear tape somewhere in the vehicle and cover a crack until a professional works on it.

  • If your windshield is old and hazed, it would be best to replace it. This is probably the best solution to prevent excess glare of the lights from oncoming vehicles from slowing your response in case of an emergency. For the same reason, windshields with any damage around the driver’s field of vision should be replaced.

  • Check your car insurance under the Comprehensive Coverage section. This is where it will say whether your insurance company covers windshield repair and/or replacement. Many people search under the Collision field, which is basically the wrong place to look. In many cases, the deductible for comprehensive coverage is no more than $100, which means that getting a new windshield will probably not cost you an arm and a leg as you originally thought!


Category: Auto Glass