A LITTLE LIGHT LEARNING: YOUR GREEN HOUSE WINDOW

A window. We may take it for granted today, but if we pause for a moment and consider its remarkable qualities, we see its critical role in your green house. It allows sunlight to fire the photosynthesis that drives all garden growth, yet protects your charges from the extremes of weather. In other words, it provides all the benefits, with none of the hazards. Your modern green house window is the culmination of a long path of development dating back to the Romans, and arriving up to the latest in polymers. This history is a fascinating path through technology and invention.




You Say Glaze, I Say Glass: Green House Window History
Glassmaking is an ancient world art that really came to an apex in the Roman Empire. Yet, even they didn’t just wake up one day and decide to make a green house window. They mostly used glass for special containers, which harkens back to the actual origins of glass.

In the ancient world the most common containers were made of clay and pottery. Most of this pottery was plain, or painted after firing. It wasn’t until later that the technologies of firing were developed to the heat levels for the modern glazes we think of now. These glazes are the closest relatives of what we know as glass.

Romans had some of the purest glass of the ancient world, but even it had too many impurities to form a green house window. In fact, it wasn’t until much later that the idea occurred to melt cylinders of glass over a flat surface, often a pool of mercury to make panes of glass at all. These two major developments led to the green house window, but it was not until modern times that production techniques made it cheap enough for everyone to be able to afford them.





The Modern Green House Window: Glass, Plastic, or Both?
The developments didn't stop with just making a flat, clear piece of glass; they have continued up to the very latest technologies. Now it is likely that a modern green house window is not even glass. These windows are typically made from a modern polymer plastic such as Lexan or Plexiglass.

Plexiglass was the earlier of the two, and came into quick favor as it not only made for less distortion when molded into curves, but also was more resistant to breakage than glass. This protected many greenhouses from loss during stormy weather. The problem with it was that after long exposure to the elements, it had the tendency to yellow and become cloudy. That led to the development of Lexan, a newer polymer that is not only stronger and lighter, but resists yellowing.

Beyond the all polymer panes, even glass itself has improved. Modern techniques make for clearer, distortion free windows, and multiple-layer panes that allow light in, but resist heat. There are even special combinations of polymer films that can tailor the light through the green house window as well as impart greater strength to the glass.

It has been a long way from the clay pot to the green house window, but fascinating along the way.