Before Bill Gates came along and changed the world, a “window” was a pane of glass that provided visibility. In homes, businesses, and in vehicles of all kinds. As buildings got taller, and vehicles moved faster, people worked on making glass stronger. The last thing a 747 pilot needs is a seagull crashing through his windscreen at 600mph. As always, the technology “trickled down” into the consumer market. Car windshields were the first example, dating from the 1930s. Hurricane windows came later.
HURRICANE WINDOWS ARRIVE
A South Florida home’s or business’s windows can experience some extreme stresses. A Cat 5 hurricane can send a solid, heavy object into a window at 200mph. After Hurricane Andrew, in 1992, Miami-Dade wrote impact-resistant glazing into its building code. Hurricane windows were written into the State of Florida building code in 1994, for specific areas. Public insurance adjusters are very familiar with them.
The code change doesn’t mean every home and business owner must refit with impact-resistant windows. Those of us who have been relying on those familiar steel shutters can continue to. However, folks thinking of retrofitting need to be familiar with the technology itself. Buyers of properties with existing hurricane windows will want to appreciate why they’re paying a premium.
WHAT ARE HURRICANE WINDOWS?
The basic idea behind car windshields, airliner windscreens, and hurricane windows is lamination. Layers, that is. The typical design is two layers of glass with another layer of plastic material between them. Applying tremendous heat and pressure bond the layers together.
This “sandwich” reacts very differently from plain glass when struck by a flying object. For one thing, the bonding of the glass layers to the polymer center means no flying glass shards. The glass may break, but because it’s “stuck” to the inner layer of plastic, it stays put. Moreover, the polymer plastic itself is very tough. It resists penetration by the flying object.
This is critical. The most severe damage to buildings from hurricanes is often the result of sudden, drastic pressure changes. When a window is shattered by a flying object turbulent air from outside rushes in. The sudden pressure change, combined with the battering from winds outside, is what blows the roofs off of buildings.
Hence, if a hurricane window gets hit by an object with a force below its rated limit, the glass layers will likely be cracked. However, the window probably won’t be penetrated. Flying glass shards won’t shower the people inside. There won’t be a sudden pressure change that can cause catastrophic damage.
Hurricane windows also are good soundproofing and good thermal insulation. They block harmful UV radiation. Having them may reduce homeowner insurance premiums, too. They are, of course, not cheap at all. Nonetheless, any property owner in South Florida who can have them should have them. This is the real windows upgrade.