How the Double Glazed Windows Works?

Double glazing consists of a set of two panes separated by an air or gas layer. It slows down heat transmission and therefore limits heat loss. Its performance is evaluated thanks to the thermal transmission coefficient, which must be as small as possible for maximum efficiency.

What is Double Glazing Made of?

The double glazing can be adapted to both windows as windows or doors. This is the best way to properly insulate the openings in your house, both thermally and acoustically. The double glazing consists of two panes: either an air gap or a gas: argon or krypton. These gases have the particularity of being fewer heat conductors than air and, therefore, more efficient in terms of thermal insulation, but they are also more expensive. On the double glazed window frame, between the panes, is placed an aluminum or synthetic material spacer. This will make it possible to eliminate thermal bridges and therefore improve the insulating power of the double glazing. To complete the device, a “desiccator,” which will prevent the humidity of the air from entering between the panes, is, most of the time, added to the assembly to prevent fogging. These are small porous beads placed under the moisture-absorbing interlayer.

Overview of the Composition of the Panes

Often you will find 3 digits (e.g., 4/6/4, 10/6/4, 4/16/4, 10/16/4, etc.) in the manufacturers’ catalogs that define the double glazing. The first and last numbers indicate the thickness of the glass. The number in the middle, on the other hand, represents the thickness of the confined air layer. Opting for double glazing also allows you to have anti-burglary multilayer glass. It can withstand up to 30 hammer blows before bursting. The only downside is in the weight, which is much higher. Note that the weight of a single glass per m2 and per mm of thickness is 2.5 kg. For laminated glass, it is preferable to add 0.5 kg per m2 and per sheet. The space between panes can contain neutral gas such as krypton, argon, or xenon. These types of gases have a higher thermal insulation coefficient compared to air. For the outer glass, various filters or treatments are provided. First of all, there are the UV and infrared filters, which return the heat of the sun in the summer, and the self-cleaning filters that keep dirt out.  

The Thermal Transmission Coefficient, an Important Factor of Double Glazing

The principle of double glazing is to slow down the transmission of heat and thus increase the thermal resistance of your openings. The air or gas located between the two panes has an insulating power and will prevent the pane located inside your home from cooling too much and too quickly. The performance of double glazing is evaluated using the thermal transmission coefficient symbolized by the letter U.

The thermal transmission coefficient can relate simply to the glazing and is then indicated by the letters Ug (for “glass”) or else the complete double glazed window with the letters Uw (for “windows”). Both criteria are important because you can have the best glazing in the world, but if it is combined with an old window, the heat transfer coefficient is high and therefore of little value in terms of insulation. It is important to know that the lower the thermal transmission coefficient, the more efficient the double glazing. This criterion is very important to claim certain financial aid. To obtain it, the 30% tax credit, for example, imposes a Uw less than or equal to 1.8 W / mK and an Ug less than or equal to 1.1 W / mK

Benefits of Installing Double Glazed Windows

Double glazing results in two panes isolated by a vacuum filled with air or gas. Indeed, certain gases or a confined air space do not conduct heat and therefore represent excellent insulators. There are different types of double glazed windows, including wooden windows, aluminum windows, and PVC windows. They have relatively the same energy performance, but your choice will have to be made, taking into account the architecture of your home and your tastes.

Both ecological and economical, the double glazed window allows an immediate reduction of the feeling of cold and of the heating consumption in your house or apartment. Quick and easy, changing your windows allows you to save up to 10 and 15% in energy. To get the best results, you should install several at the same time. In addition, by choosing to hire a professional for the installation of double-glazed windows, you will have access to the various aids provided by the state, such as the energy transition tax credit, the EEC premium, the eco-loan at zero interest rate, and many more. All these aids are intended to cover the cost of purchasing double-glazed windows.

Conclusion- The Double Glazing of Tomorrow

Although they are still not very accessible because they are very expensive, double glazing continues to be equipped with innovative technologies. Today, therefore, we find glazing with integrated Venetian blinds on the market, in this case, between the two glasses. The blind thus protect from the rays of the sun. The opacifying double glazing works with a liquid crystal film, also inserted between the two windows and connected to the mains by an electrical connection. Therefore, you can choose between translucent glazing (which hides from view without losing light) and normal transparent glazing. Even more innovative, electrochromic glazing works according to the same principle, but it also allows you to modulate the opacity and the luminosity according to your desire.