How Do You Shatter a Glass Ceiling?

With a steel spike or diamond drill.

Shattered glass ceiling


On Tuesday night, Hillary Clinton is widely expected to become the first female president of the United States, thereby shattering sexism’s “highest, hardest glass ceiling.” This possibility has loomed large all election season, and Clinton embraced the analogy at the Democratic National Convention. So, how do you shatter a glass ceiling?

With a strong tool, ideally made with steel or diamond. Because modern glass ceilings are made of safety glass specifically designed not to shatter, a fist, for example, would not be sufficient to break a glass ceiling.

Safety glass is tempered, laminated, or both. Tempered glass is heated to extremely high temperatures and cooled quickly at the surface. This creates a stronger glass that is steelier on the outside. Think of a Jelly Bean; the outside is a hard shell, but the inside is malleable. This malleability allows tempered glass to absorb more, making it four times stronger than nontempered glass (called annealed glass). Another benefit is that when tempered glass is broken, it crumbles into tiny fragments rather than jagged shards. Side and rear windows of cars are made of tempered glass. Laminated glass is basically layered glass that has clear, tear-proof laminate in between the layers to strengthen it. This way, if the glass breaks, it will stick to the plastic and not shatter. Car windshields are made of laminated glass.

With enough force, a steel-tipped hammer, like the LifeHammer, could do the trick. That’s what first responders use to break through car windows in emergencies. There are similar tools with spring-loaded steel spikes that could also work. Aim for the edges—with tempered glass, the edges are usually the weakest due to expansion that occurs during the heating and cooling process. Of course, in an actual ceiling, the edges are usually enclosed in a metal or acrylic frame, so they might be hard to reach. Really, just hit it as hard as you can.

If these tools aren’t enough, you can also use an electric drill with a diamond drill bit. Tempered glass holds high amounts of stress between layers, so if you drill a hole into it, it is almost certain to crack. Laminated glass may be made up of several layers, so to break laminated glass, you’ll need to drill through all of those. If your first hole doesn’t do the trick, keep drilling until the glass is sufficiently fractured.

Bonus Explainer: At the Javits Center in Manhattan, where Clinton will host her election night party, multiple tempered and laminated insulated glass units made by Viracon comprise the glass ceiling and façade.* The ceiling, walls, and skylights are designed for energy efficiency as well as strength. The walls are made of double-paned insulated glass, the skylights have laminated inner layers, and the ceilings and sloped surfaces are made of triple-layer insulated glass with laminated glass in the middle. This glass ceiling would be very difficult to break. To do it, Clinton would need a sharpened hammer or diamond drill, time, and determination.

The Explainer thanks John Flouhouse, the general manager of Dulles Glass, and Nancy Czesak, co-director of Javits Center renovation and first vice president of Tishman, an AECOM Company.

Correction, Nov. 8, 2016: This post originally stated that the Javits Center is in Brooklyn. It is in Manhattan. (Return.)