Energy Efficient Windows

Recent advancements in glass technology mean that our energy saving windows are more efficient than ever, helping to make your home warmer, save you money on your heating bills and cut carbon emissions. All energy efficient windows are given a rating, which measures their effectiveness at keeping out the cold, retaining heat and how much money you can save as a result.

Energy efficiency and reducing your carbon footprint is important to many Anglian customers. To help you compare the effectiveness of each of our energy efficient windows, we use the energy ratings system developed by the British Fenestration Rating Council (BFRC), which is the UK’s nationally recognised scheme for measuring window energy efficiency. The BFRC scheme is used in Building Regulations to show compliance for window replacements; to comply, every window must achieve a C rating or above.

Each window is assessed to measure how well it prevents heat loss, keeps draughts out and how well it absorbs natural free energy from the sun. This combination of factors gives an overall energy rating, ranging from A+ to G, with A+ being the highest rating.

Our uPVC windows achieve an A rating as standard - meaning that they gain more of the suns free energy than they lose through thermal transmittance. Ratings of A+ and A++ are also possible on our uPVC windows. Our A+ double glazed option makes the most of solar energy. While our triple glazed options, available up to an A++, offer the best in reducing heat loss. By installing Anglian’s windows, you’ll be confident your home will be as warm as possible, saving you money at the same time.

Cross section of an Anglian triple glazed window
Energy label Energy rating info Energy rating table
White Knight triple glazed casement window

All our uPVC double glazing windows achieve an A rating as standard. The higher the rating, the more energy your windows save, which not only makes your home warmer, but helps to keep your heating bills lower. There’s environmental benefits, too. By consuming less energy to heat your home, you’ll also be reducing your CO2 emissions.

Switching from single glazing to our A rated energy saving double glazed windows will save money and significantly reduce heat loss. Even replacing older double glazed windows to our modern A rated double glazed windows will make a difference. For all round energy performance as well as other benefits, such as better soundproofing and security, you can choose triple glazed windows, which also achieve up to an A++ rating.

Our A rated windows are available in a number of styles and for even greater energy efficiency, you can upgrade to A+ glass in some styles or opt for triple glazing, which is particularly beneficial for hard to heat rooms.

Casement Sash Tilt & Turn Bay Cottage
uPVC Wood Alu uPVC Wood uPVC Wood uPVC Wood Alu uPVC Wood
A++ rated - - - - - - - - - -
A+ rated - - - - - - -
A rated - - -
B rated -
Triple Glazing - - - - - - - - -
Sound Reducing - - - - - - -

Key performance factors for energy rating

Energy ratings are calculated by measuring three performance factors:

Thermal transmittance Thermal transmittance window

1. Thermal transmittance, (U value) - which measures how well your window retains heat. The lower the amount of heat lost and U value, the warmer your home will be.

Solar G factor Solar G factor window

2. Solar, (G factor) - this evaluates how well your window harvests the sun’s natural heat. Expressed as a number between 0 - 1, the higher the number, the better your window is at capturing heat.

Air leakage Air leakage window

3. Air leakage, (L factor) - measures how airtight your windows are. The lower the L factor, the less draughty your window will be.

The combination of these three factors provides an overall energy rating for each window.

A Rated Double Glazing

Our A rated double glazing far exceeds the current Building Regulations’ requirement for a C rating for energy efficiency, making them a great all-round choice. A ratings are offered as standard on our uPVC windows, which gain more heat than they lose over the course of a year. They suit any age of property and are available in a number of styles including casement, sash, tilt and turn, bay and cottage.

Our A rated windows have:

0.00 Air Leakage – a perfect score resulting in draught free windows.
1.4 Thermal Transmittance – a low scoring U Value which provides great heat retention, meaning more of the energy you generate from the sun is retained in your home.
0.47 Solar Gain – an impressive score obtained using one pane of Mid-Iron float glass and one pane of Low E glass, enabling the window to harvest free energy from the sun.

Our wooden casement window styles also benefit from an A rating and other window types can be upgraded to this glass to make your home warmer and more energy efficient. We are the only UK window company to offer an advanced Clearline Spacer Bar – a U-shaped bar replacing the standard highly visible aluminium spacer; which we combine with a ‘thermal bridge’ to create a sleek appearance and far greater energy efficiency in our windows.

Double Glazing

A+ Rated Double Glazing

Anglian’s A+ rated windows benefit from a pane of clear Low Iron glass, which helps your windows harvest even more heat from the sun. These highly energy efficient windows are ideal for south-facing rooms or elevations where the most natural solar heat can be gained, helping to further improve the energy efficiency of your home. These are our best performing windows for capturing the sun’s energy.

You can choose A+ rated windows in our popular window styles, including casement and sash.

Because these windows are so energy efficient, you could be gaining more free heat than your property loses, which means your home will be even better insulated.

Double Glazing

A++ Rated Triple Glazing

Our A++ triple glazing is our most energy efficient window, ever. And we’re proud of it.

Incorporating the performance features of our A rated windows, our triple glazing includes an extra pane of Low E glass which has an invisible coating, reflecting valuable heat you have captured back into your room. This makes our triple glazed windows perfect in hard to heat rooms such as those facing North, as they retain warmth and prevent precious heat from escaping.

Our only window using Krypton gas, Anglian triple glazed windows are ideal for insulating your home. Krypton gas is stable and non-reactive and its properties make it brilliant at insulation. This helps us achieve an excellent overall Energy Index of plus 32, meaning the window gains 32 kW hours of energy per square metre per year!

As well as achieving great heat retention properties, our triple glazed windows also offer great acoustics and sound-proofing qualities, helping to keep unwanted noise out of your home. They’re a great choice if you’re disturbed by excessive background noise. The extra pane of glass also help to make your home safer, making it harder for intruders to break in.

Triple Glazing

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