Technicalities that you should know to take a well-informed decision about energy saving windows

The two-layered glass panes or the gas that fills the gap between the panes, which contributes more in imparting the insulation properties to double glazed units? To find an answer to this question, you have to understand a bit of the technicality involved in the construction of double glazed units. No, you need not be a technical expert to understand how double-glazed units (DGU) work, because by using a little common sense it is possible to understand things quite easily. After all, there is no rocket science in windows construction, but there is science behind it which should be easy to understand. Knowing about it would also help to select the right windows by deciding on optimal specifications that help to save cost. However, if you are installing double glazed windows, the services about window repair Perth will not help because you cannot repair these windows.

The constructional features of DGU

Two pieces of glass placed side by side to maintain a small gap between the two, separated by a space bar comprises the window pane assembly of DGU. The entire unit is hermetically sealed. A gas or air fills the space between the panes and the trio of glass, spacer and gas act together to impart the insulation properties to windows capable of insulating homes from solar, heat and noise energy. Let us now look into each aspect of the construction.

The technical features

Space or cavity contains the inert gas or dehydrated air filled under vacuum conditions. The gas prevents condensation of moisture particles on the glass surface and inhibits the energy transmitting abilities of the assembly that enhance the insulation quality. The cavity of DGU can vary between 4 mm to 20 mm depending on the type of window and the gas used for filling the cavity. For low E energy saving DGU filled with argon gas the cavity width is 14 mm, and for dehydrated air, it is 16mm. For acoustic insulation, the cavity width would depend on the specific insulation requirements.

The action of air or gas

Dehydrated air has better insulation properties than normal air which means that the air in the cavity has a poor transmission rate during heat exchange, by conduction or convection. This happens because the molecules of dehydrated air are less dynamic and remain immobile as compared to normal air that results in lower thermal conductivity. The same properties are responsible for imparting improved sound insulation as the acoustic conductivity is also low. However, for better insulation of DGU, the use of inert gases like argon, xenon and krypton is suggested.

The insulation quality of DGU is the same regardless of the type of inert gases. Argon is most widely used because it has 34% lower thermal conductivity than air. Although air filled DGUs are slightly less in price, the thermal benefits of inert gases are higher by 30% that leads to much better savings overall. Argon can last throughout the life of windows with a yearly loss of gas not more than 5%.

Leave a Comment