Energy Efficient Windows

Energy Efficient Windows are what most homeowners want in the current climate.The glazing choice of the windows plays a part in energy efficiency. For windows to be energy efficient, double glazing or triple glazing is used. With single glazing, one-third of the heat is lost through its window pane. Double or triple glazing differ from the single glazing as they are built with:

Gas Filled Energy Efficient Windows

1. Low-emissivity glass
   There is a special coating to prevent heat loss through the glass. This coating thermally insulates the window and improves the house’s energy efficiency.
2. Low-iron glass
   Unlike other glass, low-iron glass is almost colorless and lack the green tone.
3. Warm edge spacer bar
   There is a warm edge spacer bar between the panes. The composition of the warm edge spacer bar helps to prevent heat loss
4. Gas
   The gap between the panes is usually filled up with gas, either argon or krypton. As gas is a poor conductor of heat, it diminishes the rate of heat loss through the window.

The energy efficiency of the window is as good as its installation. A poorly fitted window with gaps can leak heat and reduce energy efficiency. That is why, at Weatherglaze, we make your window to measure so that they fit perfectly and properly seal the perimeter. Our qualified professionals will measure the window to fit.

Building Energy Rating

BER or Building Energy Rating is the standard used in Ireland to measure the thermal efficiency of the house. When measuring the thermal efficiency for the window, the BER rating is based on U-value (thermal transmittance) and the G-value (solar gain). The rating for BER goes from A to G, with A being the most energy-efficient and G the least energy-efficient.

Window Energy Rating

WER or Window Energy Rating indicates the energy-efficiency of the window. WER is a certified way to measure the U-value and G-value for BER. The WER rating is worked out based on:

1. Thermal Transmittance
   It refers to how well the window keeps the heat within the house or the U-value. The lower the U-value, the better your house can keep the heat within the house.
2. Solar Factor
   It refers to the level of solar energy that is allowed through the glass, or the G-value. Low iron glass helps to allow the maximum amount of heat from the sun to enter through the glass without compromising the insulation, leading to a higher G-value. G-value ranges from 0 to 1, with a higher G-value indicating better solar heat gain.
3. Air Leakage
   It refers to the level of air that is allowed through the window seals, or the L-factor. A good quality window should have zero air leakage. The lower the L-factor, the more air-tight is the window.

All the above three ratings will determine the overall WER rating of the window, with a scale from A to E, with A being the most energy-efficient.

Where to get an energy-efficient window in Ireland?

Wherever you are in Ireland, there is always a Weatherglaze window expert to help you to select the right product for your home. Do not hesitate to book a consultation with us to get a free quote.