Double-glazed window – a design of two or more glasses connected into a single translucent block. The glass is connected using spacers and sealant. The space formed between the sheets of glass is called the air chamber. To improve the performance of thermal insulation, the chambers can be filled not with air, but with an inert gas (Argon or Krypton).
“It is hard to overestimate the role of double-glazed windows in modern windows.”
High-quality double-glazed window is the key to the quality of the entire window. It is from the double-glazed window, to a greater extent, that the indicators of thermal insulation and sound insulation of windows depend. And this is not strange, because a double-glazed window occupies about 80% of the total window area. The modern development of the glass industry makes it possible to design large-sized windows with very high insulating characteristics.
Properties and types of double-glazed windows
The possibilities of modern glass are hard to overestimate. Over the past couple of decades, coatings have evolved greatly and have made it possible to design glazing of the most unexpected shapes and sizes.
Depending on the properties and functions, double-glazed windows are popular:
- energy-saving (sputtering on glass and Argon gas in chambers)
- multifunctional (solar protection and energy saving)
- soundproofing (with hanging noise protection)
- anti-burglary (with hanging protection against penetration through a double-glazed window).
In addition to these, modern glass allows you to make double-glazed windows: shockproof, fireproof, anti-vandal, armored, tinted, artistic, and all this can be combined.
Energy-saving double-glazed windows
To date, the most popular and in demand are energy-saving double-glazed windows. The fundamental difference between such double-glazed windows is that one or more sheets of glass of this double-glazed window have a special energy-saving coating, which reduces the thermal conductivity of the double-glazed window and reflects heat flows. For greater thermal insulation, inert Argon gas can be pumped into one or more double-glazed chambers.
Argon has excellent heat transfer resistance and enhances energy-saving properties. The gas is not under pressure and is absolutely harmless to humans and the environment. Argon is an inexpensive gas and will not lead to a strong increase in the cost of the product.
Multifunctional double-glazed windows
Multifunctional double-glazed windows perform two functions: energy-saving and sun protection. In multifunctional double-glazed windows, the outer glass has a coating that reflects the flow of sunlight, and the inner glass is energy-saving (retains heat from the side of the room). To improve performance, inert gas Argon is pumped into the chambers of multifunctional double-glazed windows.
In terms of thermal insulation, multifunctional double-glazed windows are ahead of even energy-saving ones, but it is not recommended to use them by default. The fact is that such a package transmits a little less visible light and this can lead to poor insolation of the room if the windows do not face south.
Noise-insulating double-glazed windows
Soundproof double-glazed windows have increased sound insulation performance. To achieve this effect, sheets of glass in double-glazed windows are used in different thicknesses. So, for example, unlike ordinary double-glazed windows where, as a rule, glass is used with a thickness of 4 mm, in noise-insulating double-glazed windows, outer glass is used with a thickness of 6 mm or 8 mm. This avoids the entry of glasses into resonance when a sound wave passes through them.
Also, special triplex glass with a noise-insulating film can be used for noise insulation. As a well-known example of the use of this type of glass, one can cite the windshield of a car. Tripkleks at the same time as noise insulation is also safety glass.
Anti-burglary double-glazed windows
Anti-burglary double-glazed windows Kyiv significantly increase the time for intruders to pass through the structure. Unlike conventional double-glazed windows, anti-burglary ones have one or more triplex glasses in their formula. Triplex – two or more layers of glass glued together through a film. To penetrate the room through triplex glass, it will take a lot of time and all this will be accompanied by noise. Anti-burglary double-glazed windows are really very reliable and effective protection against unwanted guests.
Tripplex allows you to make windows of very large sizes and not worry about safety in case of glass breakage or attempted breaking of the window. On the territory of many Western European countries, triplex is mandatory for use on high-floor balconies.
Double glazing formula
Formula – a set of data on all parameters of a double-glazed window. The formula displays: the depth of the double-glazed window, the number of glass sheets, the type and marking of glass sheets, the material and width of the spacers.
An example of decoding a two-chamber energy-saving double-glazed window with the formula: 6-14-4-14Argon-4i
- 6 – thickness of the outer sheet of glass, mm
- 14 – distance frame, mm
- 4 – thickness of the inner sheet of glass, mm
- 14Argon – distance frame 14 mm, chamber filled with Argon gas
- 4i – internal glass 4 mm with energy-saving coating
Depending on the selected options and overall dimensions, the necessary formula is selected, which will later be indicated in the product passport. Knowing the formula, you can easily calculate all the indicators of the product using the online service.
The number of chambers in a double-glazed window
Depending on the number of chambers, most often double-glazed windows are: single-chamber (two sheets of glass, one air chamber between them) and two-chamber (three sheets of glass, two air chambers between them).
Theoretically, the number of cameras can be more than two, but in practice, this makes no sense. Double-glazed windows of more than two chambers are too heavy and are not justified in terms of functional characteristics.
The best option for residential premises is a double-glazed window. At the same time, its depth can be completely different, and the quality indicators of the product depend on the correct selection of the distance and the thickness of the glass. Two air chambers make it possible to achieve the necessary indicators as not only thermal insulation, but also sun protection.
Distance frame (distance) – a special profile to which glass sheets are glued to form a double-glazed window. The standard distance is made of aluminium. A large selection of different frame widths makes it possible to dial the required width of the double-glazed window. To absorb moisture, silica gel is poured into the frame.
The distance frame could be not only aluminum, but also combined (warm). This frame allows you to reduce heat loss due to the absence of cold bridges. The warm spacer is recommended for windows with high thermal insulation requirements. It is worth noting that this solution makes it possible to choose the color of the frame. The warm frame reduces the chance of condensation in the edge zone.
Comparison of characteristics of double-glazed windows
- energy-saving glass
- Argon gas
|Visible light transmission (τv)||70 %||74 %|
|Reflection of visible light outside (ρv)||14 %||20 %|
|Reflection of visible light from the inside (ρv)||14 %||20 %|
|Color rendering index (Ra)||96,6||96,7|
|UV transmission (τuv)||20 %||49 %|
|Direct transmission of solar energy (τe)||41 %||62 %|
|Reflection of solar energy outside (ρe)||32 %||17 %|
|Reflection of solar energy from the inside (ρe)||32 %||17 %|
|Heat gain from solar radiation (ρe)||0,50 %||0,70 %|
|Heat transfer coefficient winter night||0,74 W/m² · С||1,73 W/m² · С|
|Heat transfer coefficient summer day||0,55 W/m² · С||1,81 W/m² · С|
|Heat transfer resistance Rcenter
(☝ the higher the value, the better the energy saving)
|1,34 m² · С/W||0,58 m² · С/W|
|Soundproofing Rw||35 dB||35 dB|
|Glass unit weight kg/m2||28,79 kg/m2||28,79 kg/m2|
|Glass unit depth||52 mm||52 mm|
|Number of glasses||3 pcs.||3 pcs.|
|Number of cameras||2 pcs.||2 pcs.|
|The cost of 1 sq.m.||3 280 ₴/m²||2 533 ₴/m²|
How long will Argon be stored in an insulating glass unit?
Modern technologies for the production of double-glazed windows make it possible to ensure the presence of Argon gas in the chambers of double-glazed windows for the entire period of operation. Studies have shown that a high-quality double-glazed window loses up to one percent of its filling per year.
Will flowers grow in a room with energy-saving double-glazed windows?
Yes, modern energy-saving double-glazed windows will not affect indoor plants in any way.
How can I check that a double-glazed window is energy efficient?
There is a special device to confirm this. But, at home, it is possible without a device: by bringing the flame from a burning match or lighter to a double-glazed window, you will see several (depending on the number of glass sheets in the double-glazed window) reflections of the flame. Display on energy saving glass will differ from display on non-coated glass.
Will it be darker with energy-saving double-glazed windows?
Energy-saving spraying is transparent and invisible to the human eye. The light transmission of such glass is slightly lower than that of uncoated glass, but visually you will not feel the difference.
Is it worth installing multifunctional double-glazed windows in all rooms?
Solar control glass transmits less visible light than energy-saving glass. Multifunctional double-glazed windows are recommended to be installed only in those rooms that are really exposed to excessive solar radiation. Otherwise, the room may be dark (especially if the window is small).
How long does glass replacement take?
Installation of one double-glazed window takes 15-20 minutes.
What double-glazed windows protect against a blast wave?
Double-glazed windows with triplex glass will perfectly protect against the potential danger associated with fragments.
Why is tempered glass better?
Tempered glass is many times stronger than ordinary glass and in case of destruction it is safe for humans.
How to protect double-glazed windows from a shock wave?
The most effective way is a mesh of adhesive tape. It will not protect against destruction, but it will protect you from splinters.
Windows are leaking, what should I do?
In 90% of cases, the condensation problem is related to the high humidity in the room, and not to the double-glazed window itself.
How are double glazing made?
Double-glazed windows are made on modern production lines. First, sheets of the required size are prepared, and then they are glued together through a spacer frame.
What gas is pumped into double-glazed windows?
Most often, Argon gas is injected.