About Energy Efficient Glazing
Energy efficient glazing offers many benefits. It can make your home warmer, will make you home quieter and also help in reducing your energy bills.
So how does energy efficient triple and double glazing work?
What is energy efficient glazing? Let’s start with how double and triple glazing works. Double glazing is made with two sheets of 
glass with a gap between them which creates an insulating barrier that keeps cold out. Triple-glazing has three sheets of glass, again with an insulation barrier. Often the gaps are filled with an insulating gas. However, having double or triple glazed windows doesn’t guarantee high insulation, you need to consider the BFRC Rating, which provides you with guidance on how energy efficient window units are.
Modern, energy-efficient windows are now made in a wide range of materials, not just uPVC, and the energy-efficieny rating is different from window to window. These differences include how:
• efficient are the windows at preventing heat passing through them
• much sunlight is able to get through the glass
• much air, ideally very little, can leak in or around the window
What should you consider?
Glass
On the current market, the most energy efficient glazing is low emissivity (Low-E) glass. Often, this has an invisible coating of metal oxide on one of the internal panes. It works by letting in heat and light, but prevents it getting out.
The gaps between the glass
The highest energy-efficient windows use gases like krypton, argon or xenon between the sheets of glass.
Pane spacers
Pane spacers are small blocks that are set around the inside edges to keep the two panes of glass apart to provide maximum efficiency. They are ideally “warm edge” spacers and contain no or minimal amounts of metal.
Frame materials
For all frame materials there are windows available in all energy ratings.
• uPVC frames last a long time and may be recycled.
• Wooden frames can have a lower environmental impact, but require maintenance. They are often used in conservation areas where the original windows had timber frames.
• Aluminium or steel frames are slim and long-lasting, and may be recycled.
• Composite frames have an inner timber frame covered with aluminium or plastic. This reduces the need for maintenance and keeps the frame weatherproof.
Energy rating
Some window manufacturers show the energy efficiency of their products using an energy-rating scale from A to G. This means that the whole window (the frame and the glass) is assessed on its efficiency at retaining heat.
U-values
Windows that have an energy rating will have the u-value of the window displayed on the energy label. A u-value is a measure of how easily heat can pass through a material. Materials that let out more heat have higher u-values whereas materials that let less heat pass through them have lower u-values.
In some cases, a higher energy efficient glazing performance rating might have a higher u-value than windows with a better energy efficiency rating. This might seem the wrong way round as lower u-values indicate better insulation levels. However, in these cases it will be that there are other aspects of the window that make them better overall such as coating used on the glass and the gap between the glass panes.
Ventilation
Replacement windows will be more airtight than your original frames, so condensation may build up in your house due to the reduced ventilation. If your house does not have much background ventilation, look for replacement windows with trickle vents incorporated into the frame to let in a controlled amount of ventilation.
If you start to see condensation building up around your windows, there may be a damp problem in your home. As a general rule, damp occurs when there is inadequate ventilation, inadequate heating, inadequate insulation or a combination of these. If you’ve started to notice condensation in between the panes of glass in your double-glazing units then it is likely that the seal is broken, and the unit will need to be replaced.
If you would like a no-obligation quotations to replace your existing windows with energy-efficient glazing, contact Northampton Double Glazing experts, Vividways today?
