5 interesting facts about windows

There's a lot more to a property's windows than meets the eye. Find out 5 interesting facts about glass windows and how they came to be what they are today.

1. Defining the window

The English word ‘window’ originates from the Old Norse era and was first recorded in the early 13th century. Early Norse homes were of a simplistic design, typically including a stable area to house people and their livestock under one roof. In the winter, when the doors were closed, smoke from the indoor fires along with stale air would fill the room, so they started to add unglazed holes to the top of the walls and in the roof to allow for better ventilation.

These openings were referred to as ‘‘vindauga’ (vindr meaning “wind” + auga meaning “eye”  – literally translating to wind-eye). Many years later, the British implemented a similar practice, and the translation of the word shifted to ‘window’.

2. History of the glazed window

Prior to the invention of glass, windows would be formed of paper, cloth, animal hide, or thin slices of wood or stone. It is thought that the earliest “glazed” windows would have been produced by the Roman Egyptians in about 100 A.D but the glass would have been so thick it would have been almost impossible to see through them. More than a millennia worth of development stands between those early models, and the types of windows we manufacture today.

Glass windows only became common in homes in the early 17th century. In the years preceding this time, they were seen to be a luxury item, with even the wealthiest of people only fitting them into their most important rooms. Windows were such a prized possession that aristocrats would have their windows taken down and stored in their absence while they were away visiting their other estates.

3. Introduction of the window tax

First imposed in England in 1696, the window tax was introduced to make up for losses caused by clipping of coins (literally chunks missing from the edge of silver coins reducing their weight and therefore their intrinsic value) during the reign of William III. The tax was enforced throughout the United Kingdom and many European countries during the18th and 19th centuries, and was based on the number of windows in a property.

Campaigners argued that it was a “tax on health”, and a “tax on light and air”, as well as being an unequal tax with the greatest burden being felt within the middle and lower classes. As a result, many homeowners attempted to avoid paying the tax which is why some properties from the period have bricked-up window-spaces. 156 years after first being introduced, the window tax was repealed.

4. The arrival of double glazing

There is evidence to suggest that a proportion of houses in Scotland had double-glazed windows as early as the 1870s, however, this took the form of a single sheet of glass puttied on to the existing window which is a far cry from what we are used to today.

In the 1930s, a U.S inventor created the Thermopane – two layers of glass bonded together in a single frame, trapping a layer of air in between. Such a concept was extremely expensive to produce in the 1930s, and it wasn’t until 1941 that a manufacturer was willing to start producing the concept, and in around 1952, double glazing entered the residential market.

Although homes in the U.S. had been enjoying the benefits of double glazing since the 1940s, the UK didn’t start to catch up with the double-glazing craze until the 70s. Prior to this time, high costs and a lack of incentive from the relaxed building codes of the time put many off investing, until the arrival of cheaper materials saw their popularity increase. This, paired with the need for the UK to rethink its dependence on foreign suppliers and oil during the ‘Energy Crisis’, the UK soon jumped on the double-glazed bandwagon. By the 90s, double glazing in homes had increased from just 16% in the 70s to over 60%.

5. How many windows does a property need?

While the average UK house will likely have somewhere between 8 – 15 windows, the White House in Washington D.C. holds 147 windows and Buckingham Palace boasts a whopping 760 windows. More impressive still, the Empire State Building, New York has 6,500 windows, and the tallest building in the world, the Burj Khalifa in Dubai comprises a total of 34,348 windows.