A significant portion of heat escapes from our homes through windows. Measurements show that about 30% of heat losses—in the form of radiant energy and the energy of air molecule movement—occur precisely through window glass. In the case of a loose fit of the window frame to the opening, these percentages are supplemented by the natural 'escape' of warm air outside through gaps and microcracks at the contact point of the frame and window casing. How do they combat this in Europe?
Theoretically, even classic frames (double or triple) can reliably protect a home from heat loss. But. In practice, it is impossible to create two identical frames that exactly match the dimensions and geometry of a window opening. The situation seemed to improve when plastic windows were invented and tested (in 1952, in Germany) – sealed structures made of PVC profile with a built-in double-glazed unit.
Initially simple, single-chamber PVC windows provided a sufficient level of heat saving. However, over time, their efficiency somehow came to be considered low—the reason being the general Western trend toward environmental friendliness—including in construction. The emergence of new woodworking machines, providing greater precision in manufacturing the finest wood parts, led to the boom in 'green' technologies in construction receiving material support.
Since then—roughly from the mid-1980s—Europe has increasingly looked at the world through wooden windows. But not the type of windows that in our country are called 'Soviet,' but real double-glazed windows, only not on a plastic profile but on a wooden one. As experts have proven, their energy efficiency is no worse than that of PVC windows.
Today, at the beginning of the 21st century, almost 60% of windows in residential buildings in Europe are wooden, created on the same principles as earlier PVC windows. Moreover, glazing itself has not escaped modernization. Europeans (and we after them) recalled the results of heat loss measurements—in particular, about radiant energy, which is lost regardless of how precisely the profile is fitted to the window opening size.
The result was the emergence of heat-saving glass, as well as tinted glass. Their feature is the ability to conduct radiant energy (infrared waves, which are the 'carriers' of heat) in only one direction—into the room. However, infrared waves emitted by heated household items, furniture, and even walls are repelled by such glass.
So, today Europe looks at the world through heat-saving windows—wooden, with glass that does not let heat escape.
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