One may wonder just what makes windshield glass so different from regular window glass. Can window glass be used as a less expensive alternative to windshield glass? Aren’t they pretty much the same?
In short, the answer is “No”.
Windshield glass and standard window glass vary slightly, but this variation makes all the difference. Windshield glass is designed with optimum safety in mind. To explore further, let’s first take a look at what comprises standard window glass.
There are several raw materials commonly used in the making of glass. A mixture for the production of ordinary glass usually involves sodium silicate, calcium silicate and silicon dioxide. The process of creating such glass is called the “float glass process,” where these chemicals are heated to a molten state and let flow in a continuous stream onto a molten tin bath. The top layer of this glass is then treated by nitrogen to obtain a nice, polished finished product. The end result is, indeed, something that is nice to look through…just not while you’re driving.
Now for the small variation that makes a huge difference.
As mentioned before, windshield glass is designed for optimum safety. Your windshield is comprised of two pieces of glass, separated by a thin layer of vinyl (called polyvinyl butyrate, or “PVB”). This thin layer “glues” each piece of glass to the other, helping the windshield as a whole stay intact in the event of a collision. Instead of large shards of glass, windshields will break into lots of smaller pieces, decreasing the likelihood of serious injury. This also makes it more difficult for objects outside of the car to break through the windshield, and vise-versa.
