Everything You Need to Know About Glass in Windows

You can not truly appreciate something fully without knowing its history. In order for us to appreciate something, we must learn how it came to be—the long story of how it was created and perfected until it became the thing we know today.

Glass in windows have been cruising the course of history with us humans for a long period of time now. Along with us, its technology and composition has been developing over time. You’d be surprised by how much people from the past dedicated time to develop this product for our windows, which might be the reason why it is one of the most essential parts of our houses today.

multi-paned windowsThe use of glass in windows for normal houses can be traced back to the Roman era. The earliest kinds of glass were panes of shiny and glassy pebbles carefully fitted in to a wooden frame. Unlike present day windows, only a little light passes through the pebbled window pane, through the gaps from each pebble. Though it is far from the flat and transparent glass in windows we have today, it is considered the dawn of its invention.

The clear glass panes we know today were recorded to be invented in the late 3rd century CE. Glassmakers would blow on to bubbles and produce glass cylinders and later on cut them in half to produce flat and lengthwise end products.

During the Dark Ages, the technology of glass in windows and its other alternates was lost, consequently following the fall of the Roman Empire from where it was first used. During this times, the windows of domestic houses were wooden panels of wood, arranged into shutters with the sole purpose of keeping the cold outside the house. Worse, people had no other choice but to use oil-soaked animal hides—which is as thin as present day parchments, to cover up their window sills.  Because of the absence of glass in the windows, people converted their doors and windows in to smaller holes to minimize the drafts. Because of this, most houses are generally dark because the sunlight has no way of entering inside their homes.

But, also during this time, the Catholic churches across Europe began coloring glass and putting up stained glasses as both decoration and narration of the mysteries of the rosary in illustration.

Come the Middle Ages, the glass window technology had its second chance. More and more methods were developed to manufacture flatter and smoother window glasses. The science of glass blowing was further enhanced during the 14th century. Professional glass blowers learned to create “crown glass” which are glass in forms of flattened discs, produced by carefully spinning a hollow bubble of glass. Because of this innovation, window glass became increasingly common during the mid-16th century. But it is worth noting that yes, it grew common, but not affordable. Since the process of making flat and smooth glass to be used for windows is intricate and very specific, even the wealthy found it a luxury—having Glass installed in the  windows in the most important rooms alone, while the rest of the house’s windows remained wooden. As the century progressed, more and more people learned how to make close to perfect glass that the material became more and more available, hence, affordable. Before the turn of the century, the glass making technology has been continuously developing.

Time passed and the development of glass in windows is far from over. The French, known for their love of great art and architecture have figured out the perfect art of cutting glass with smoother edges, making way for flatter and clearer panes than ever before. As a matter of fact, the world famous Hall of Mirrors—staging perfectly cut glass on its façade as well as its windows was built during this time of discovery.

As more years passed, the quest of perfecting glass for windows have been a competition for countries. The quest to produce the strongest, clearest, flattest glass for windows is still ongoing today, since our technology keeps on developing and advancing. Some changes include the use of steel, instead of wood as window frames to reduce the weight of windows.

Today, the use of glass in windows does not only translate to functionality, but also as a way of expressing design and personality among houses. Some even go beyond the traditional and make their glass in their windows the centerpiece of their homes. 

Glass for Windows Fun Facts:

  • The ticker the glass in a window, the lesser outdoor noise can be heard from the inside.
  • On the average, 15% of house walls is comprised of windows.
  • Light can pass through glass because it has a random molecular structure. Making it the only solid thing that can be penetrated by light.
  • Have you noticed that thicker pieces of glass have more greenish tint on it? This is because of the minerals found in the composition of glass itself. Since majority of the people like thick glass pieces yet uncolored, manufacturers add different minerals to neutralize the color.
  • You can never stop a crack once a glass window started to When glass breaks, the cracks move at speeds of up to 3,000 miles per hour.
  • Glass takes over 1 million years to decompose in our landfills and dumps. Glass recycling is highly encouraged, since the quality of glass doesn’t decrease no matter how many times it has been reused.
  • Hydrofluoric acid will dissolve glass.
  • The term glass developed during the later years of the Roman Empire. Tier was one of the centers of glassmaking during those period, which is present day Germany. The word glass came from the Latin word “Glesum” which is probably from a word from the German descent which means transparent, lustrous substance.

Author: Graeme Clarke

graemeGraeme has been in the joinery/glazing industry for 29 years originally as a wooden & aluminium joiner before entering the glazing industry. Graeme owned and managed a double glazing melbourne that grew to have a fully automatic Lisec double glazing line.

Erin Emanuel