Improve Your Homes Energy Efficiency
Did you know that the average home in the UK loses 25% to 30% of its heat through the windows? Learning how to save energy can help lower your energy bills, and one of the best energy saving tips is to install energy efficient doors and windows. Doors and windows that are energy efficient keep heat from escaping your house and make your home more comfortable, with fewer draughts and cold spots and less money spent on heating costs. They also reduce noise pollution, by insulating your house against outside noise. Here, we look at the different types of energy efficient windows to help you determine how best to improve your home’s energy efficiency.
With so many options available, how do you determine which windows are most energy efficient? You can’t tell just by looking at them, but the British Fenestration Rating Council (BFRC) has developed a scheme for measuring window energy efficiency, with rankings from A to G. When the system was developed, windows with a WER (Window Energy Rating) of A were the most efficient windows, but as efficiency has improved, numbers have been added to further upgrade a window’s status by adding a number to the A. For example, an A1 window is better than an A window, and A2 is better still. Above an A10, the window gets an A+ rating and the A++ rating, introduced in 2015, is given to windows above A20. To receive an “Energy Saving Recommendation” certification, a window must have at least a C rating. Installing energy efficient windows helps keep heat in your home, saving money on energy bills, and the more efficient the window is, the more money you will save.
What Is The WER Rating?
The WER rating is based on three different factors:
- The U value measures the thermal efficiency of a window. In other words, a window’s U value measures a window’s heat loss, taking into account how much heat is transferred from the warm side of the window to the cold side. The type of glass used in a window has an impact on the U value, with low emissivity (low-E) windows reducing the transfer by as much as 40 percent over conventional window glass. The lower the U value of a window, the warmer it will keep your home.
- The G value measures solar gain. By looking at the G value, you learn how much heat a window captures from the sun’s rays. The G scale goes from 0 to 1, and the higher the G value, the higher your solar gain. If your window has a high G value, it’s good at reducing your heating costs by bringing the sun’s free heat energy into your home.
- The L value measures air leakage. If your window has a weak point, like a faulty rubber seal, it will allow air to leak into your home. L value is a measurement of how airtight your windows are, and windows with an L value of zero are less draughty and more energy efficient.
The scores of a window are independently verified, and you can easily determine how energy efficient a window is by looking at the U, G, and L values. The WER rating is helpful, because it takes into account all three of those factors and assigns a score to the windows, so you don’t have to think too much about the other numbers. So, what makes a window energy efficient enough that it earns a high WER score? As we can see from the U, G, and L values, energy efficient windows are made of materials that keep heat from passing through to the outside, allow sunlight in, and don’t allow cold air to leak through. To make a window energy efficient, manufacturers make it of two or three glass panes, sealed into a frame.
Double-glazed windows are windows with two panes of glass, with a gap between them, filled with air or an inert gas, typically argon. Double-glazed windows have several advantages over single paned windows because they add a layer of insulation, increase the security of the window, reduce condensation, and reduce the noise coming in from outdoors. Triple-glazed windows, which are more expensive, are designed the same way, but with three sheets of glass instead of two and two gaps instead of one. Often, this makes them more energy efficient than double-glazed windows, but it doesn’t always. If you can’t afford double or triple glazing, you might consider secondary glazing, which is a less expensive option. Secondary glazing involves installing a second pane into a single-glazed window, which is similar to double glazing but does not have the same impact on your home’s energy efficiency.
Double and triple glazed windows are an investment, but the savings are significant. Depending on the type of home you have, you could save up to £120 a year on your energy bills by installing double-glazed windows with a high WER. Of course, the materials used around the glass matter, too. The most efficient materials for window frames include uPVC, composite, wood, and fibreglass. In contrast, metal frames like aluminium are poor thermal insulators.
How do you know when it’s time to replace your windows?
If your current windows were installed 15 to 20 years ago or don’t have double glazing, it’s time to consider replacing them with energy efficient windows. Of course, if they’re not opening properly, the locks aren’t working, or the glass has been smashed, those are also signs it’s time for new windows. If you’re noticing draughts around your doors, upgrading to energy efficient doors may be the best course of action to take. New external doors require approval from the relevant buildings control body, so they are typically insulated to comply with regulations.
Before installing new windows, you’ll need to find out if there are any restrictions on what you can do to your windows. You can do this by checking with the local planning office to determine if you live in a conservation area, you have an article 4 direction on your property, or you live in a listed building. Conservation areas are places of special interest, either architecturally or historically, so there may be restrictions on what can be done to the windows. You may be allowed to replace the windows if your new windows are in keeping with the character of the building and area. Similarly, listed buildings are historical properties that may be protected for their appearance as well as the materials and methods used to make them. If you have sash windows in your home, you may need to upgrade them with windows that resemble the original design but are more energy efficient. Of course, if you live in a home where it’s impossible to install double or triple glazed windows, for whatever reason, good-quality secondary glazing may be a worthwhile option. You can also help insulate your windows by using heavy curtains, either by themselves or in conjunction with secondary glazing.
If you’re concerned about the cost of installing energy efficient windows, there are grants that may be able to assist you. There are not yet government funded energy efficient window grants in the UK, but there are others, such as the Home Repair Assistance Grant, The Care and Repair Scheme, and The Housing Air for Older People Scheme. It might be worth your while to look into these grants to determine if you meet the eligibility requirements, or contact your local authority to learn if you’re entitled to a Home Improvement grant.
Once you’ve replaced your windows, your new windows will be more airtight than your original windows. Because of this, condensation may build up in your house because of a reduction in ventilation. If your house does not have adequate background ventilation, replacement windows with trickle vents in the frame can be a viable option to allow a controlled amount of ventilation to come in. If condensation appears between the panes of your double glazed windows, however, the seal is probably broken. In this case, you’ll need to replace the entire unit. Whenever you have windows installed or replaced, choose an installer registered with one of the official competent person schemes, so that you can be sure your windows are in compliance with the UK Government’s building regulation standards.
Call Adams Window Centres today!
Established since 1994, Adam Window Centres has been successfully managed throughout by Peter and Lesley Rowles. Their passion for customer satisfaction and unrivalled quality has elevated the company to one of Dorset’s leading independent home care specialists, awarded the British Standard in 2009. We are committed to meeting our customer’s needs with efficiency, effectiveness, and fairness, providing quality installations, surveyed and installed by our own employees, using no sub-contractors. Our prices are fair, with best prices given from the outset and no hard sell tactics used, and all of our work is covered by a ten year guarantee. To see our work, visit our Gallery Page or stop by our showroom in Dorset to experience our products first-hand. You can also call 01202 031151 or contact us through our website.