Tag Archives: glass

I’m sorry if this ends up being unrelated to the actual blog, but I’ve always wondered how defenestration should work believably. Say, someone was thrown out of a window, or through glass, or even jumped through glass on purpose. Would a regular window shatter, like in movies, if someone was thrown into it/pushed in a combat situation. How would this affect their ability to fight?

Okay, first caveat, I’m not an expert on glass, either being thrown through it, or breaking it…

Films used to use something called sugar glass. This was basically a transparent candy that looked enough like glass on film, but was brittle enough to shatter without tearing someone’s hand apart. (I seem to recall this stuff was actually edible.) According to a quick web check, they’ve moved over to synthetic resins in the past few years, so in films where you see someone punching glass or getting thrown through windows, they’re either going through a sheet of candy, or a polymer.

Real glass comes in a lot of different varieties, with a lot of different characteristics. The glass in modern cars is designed to shatter into small cube-ish pieces with relatively dull edges. They’re then coated in a plastic sheath to keep the window from spraying everywhere in the event of an accident. The windshield itself is made from a slightly different reinforced glass; that will break around point of impact. Though, this can take someone being thrown into it.

I’m not 100% certain about glass in residential or commercial construction. This should be able to withstand the force of someone being thrown into it, or survive a stray punch. Anyone with a weapon or tool should be able to shatter glass with it, specifically I’m thinking of claw hammers, crow bars, tire irons, baseball bats, or golf clubs.

Reinforced glass (with a metal crosshatch) is designed to take a lot of physical abuse. I’m not sure how much force is needed to break this stuff, but it’s a reasonable guess that a crowbar wouldn’t be enough.

Ballistic glass is basically just an amalgam of two different sheets of glass designed to absorb gunfire. It can be penetrated with enough force, but you’re going to need high powered weapons to get through it. I remember reading a few years ago about the introduction of an aluminum compound into ballistic glass, that pushed it’s durability even further, but, I don’t think that has made it into the commercial sector yet. I have no idea what explosives will do to either variety.

Punching through a sheet of glass can result in some pretty serious injuries to someone’s hand. Most glass tends to break in a spiderweb pattern from the point of impact. The individual wedges are very sharp, and will tear through someone’s muscle tissue. Throwing someone through has a similar effect, except instead of just mangling their hand; it will be their entire body. The statement about three inches of penetration holds; If they end up with a shard of glass that penetrates into their body, they’re probably going to die quickly.

There’s actually a similar risk if someone uses explosives on a window. The explosive itself should force most of the glass away from the character setting it, but anyone on the other side will risk being impaled by flying glass shards.

Getting thrown out of a window above the second floor is also pretty serious. A bad landing will kill them, and even a good one can shatter bones and leave them unable to move. Obviously, there are a lot of factors, a few people have survived falling out of airplanes (without chutes) while a bad landing can kill from a six foot drop.