Factors to Consider When Buying Double Glazed Windows

If you are planning on buying a new type of window for your house, you may not want to settle for anything other than double glazed windows.  Double glazed windows are among the best types of windows in the market today because of their energy saving capabilities. However, it doesn't mean that they can directly reduce your electric bill. Instead, they influence your electricity usage by better insulating your home, which gives you no reason of turning on your heater or air conditioner. But how do you know the right type of double glazed window for your home? Well, there are different factors to consider and the following guide better explains these factors.

Window Energy Ratings

The Window Energy Rating (WER) system is a scale that grades windows in terms of energy saving capabilities. The scale runs from A to G, where A is the most efficient type of window when it comes to saving energy. G, on the other hand, is the worst. If you were to switch from one class of double glazed window to a higher one, say from B-rated to A, you would end up reducing your energy bills by 6.5%.


Several factors are taken into consideration when the WER scale is made. One of them is the U-value. U-value is the measure of a double glazed window's ability to transfer heat. A double glazed window that has the lowest U-value is the best insulator against heat loss and vice versa.

Solar Heat Gain Coefficient

Another factor that is taken into consideration when making the energy ratings is the Solar Heat Gain Coefficient (SHGC). It looks at the ability of a double glazed window to transmit or conduct solar heat energy in a room. The higher the SHGC, the greater the ability of a double glazed window to conduct solar heat. SHGC scale runs from 0 to 1.

Pane Spacers

Panes spacers are fixed inside the edges of the windows to keep the two glass panes separate. But, besides that, they also play a part in heat maintenance. Spacers that have been made with no metal (warm edge spacers) are the best.

Low emissivity (Low-E) windows are among best type of double glazed windows. They are A-rated type of windows due to their high thermal insulation properties. They are made of warm edge spacers and the cavity between the two sheets of glass is filled with argon to prevent heat from escaping. On top of that, the window has a metallic coating that does two important tasks: reflecting heat back inside and allowing penetration of light and heat from the sun.