How to choose energy efficient windows for your home.

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With increasing concern about forecasts for a colder winter this year, many of us are worried about the soaring cost of energy bills. If you’re a homeowner who’s worried about the rising cost of your heating bills this winter, and are interested in exploring ways to ensure that your energy bills stay on track, your windows could be one of the major factors in your home that could help you do just that.

Energy efficient windows are increasingly becoming the smart choice for homeowners who not only want to reduce the costs of their energy consumption, but are also interested in being eco-friendly by saving energy and reducing the consumption of fossil fuels by making their home more energy efficient.  

How do energy efficient windows work?

To ensure that double glazing windows for your home are energy efficient, manufacturers use certain innovative technologies. The special glass used in energy saving windows is called low emissivity glass, otherwise known as ‘low- e glass’. Since our high school science lessons, we know that heat always flows towards the cold. Therefore, if your windows do not have a low-e coating, the heat from your home will be absorbed through your windows and will flow outside, where it is colder. The energy will be lost continuously as the windows continue to keep pumping heat away from your home and your boiler will keep working continuously to generate more heat, as a result of which, your energy bills will soar sky high.

Low-e glass, on the other hand, has a special coating which makes it a poor radiator of heat and does not allow the heat to be transferred to the outside. Instead, the low-e coating actually reflects the heat back into your house, thus helping reduce the loss of heat and also reducing energy consumption. The special glass also helps block the rays of the sun (up to 90% in most cases). This innovative technology actually works to the benefit of your home across seasons in winter, it keeps the heat inside where it’s needed most and in summer it keeps the heat out.

Protecting your home against adverse climatic effects Energy Saving Trust infographic

Due to the effects of increased global warming, we are witnessing extreme weather conditions across the world with winters becoming colder and summers getting hotter. Energy efficient windows are a smart choice for the savvy homeowner as it protects your home against climate change. Yet another fallout of climate change are holes in the ozone layer created through release of chlorine, bromine and other toxic gases in industrialised societies. The depletion of the ozone layer has resulted in large amounts of harmful ultraviolet B rays to pass through, resulting in an alarming increase of skin cancers and cataracts in humans.

In the UK alone, around 13,300 cases of malignant melanoma are being diagnosed each year since 2011 and 102,000 patients of non-melanoma skin cancer (source: People aged 65 or more are at increased risk of these diseases than younger members of our society. At the same time, we all know that sunlight can be good for us and is an important element in increasing our bodies supply of vitamin D, serotonin – the ‘happiness’ chemical and testosterone in men. Energy efficient windows therefore play an important role to ensure you can enjoy sunlight streaming into your home, without the harmful effects.  There are also many glazing options, which include tints, gas fills, and reflective coatings. Again, these are all used to help save you on your heating and cooling costs.

Other advantages of energy efficient windows

Apart from the benefits to your home discussed above, energy efficient windows have a few more advantages that you should consider. Most energy efficient windows now incorporate uPVC or composite frames. This reduces gaps in your windows and improves you home by reducing the number of draughts or cold spots. Additionally, these double glazed windows are instrumental in keeping out external noise pollution. This is particularly advantageous if you live near a busy high street or in a noisy neighbourhood. Lastly, energy efficient windows substantially reduce the amount of condensation inside the house. This means lesser moulds and damp spots inside your home – another common health hazard.


Check our summer offers and get your discount code on our double glazed aluminium and uPVC windows before the end of August! Limited time only!



Government Grants

There’s a total of £540 million available in the form of government grants for energy saving home improvements over the next three years to eligible homeowners in England and Wales declared in 2014.  Households could be granted up to £7,600 to improve the energy efficiency of their homes, which includes £500 if you have moved into a new home within the last 12 months. Older homes which are less energy efficient and are more difficult to treat would benefit from larger grants

The Energy Companies Obligation, or ECO also provides funds to eligible homes for energy efficient improvements, which include energy efficient windows. These funds are usually available through the energy suppliers and targeted at vulnerable or low income households although all households may apply. So, if you’re thinking of improving your home’s energy efficiency by installing energy efficient windows, you could be eligible for a grant to help with the costs. Energy efficiency savings are substantial and many homes across the UK saved £175 in energy costs on average last year by installing energy efficient windows

So, how much could you save by installing energy efficient double glazing windows in your home? A study conducted by the Energy Saving Trust looked at homes across England, Scotland and Wales that installed double glazing energy efficient windows to replace all their single glazing windows. Here is a table that summarises the savings generated by these households:  

Energy rating


Semi detached

Mid terrace



A rated

£120 - £160

£85 - £110

£65 - £90

£55 - £75

£40 - £60

B rated

£110 - £145

£75 - £100

£60 - £80

£50 - £70

£40 - £55

C rated

£110 - £135

£75 - £95

£60 - £75

£50 - £65

£40 - £50

These savings are for typical gas-heated homes.

How to choose energy efficient windows that are right for your home

There are many factors to consider when looking for the right windows for your home. Of course, we have earlier spoken about the type of glass:  ‘low-e glass’ which is important to look for. Efficient windows are also gas filled between the double panes of glass. Usually rare gases such as Argon, Xenon or Krypton are good choices by the manufacturer as they do not conduct heat and also block out sound. Pane spacers are used to keep the panes apart. A good quality energy efficient window ensures that almost no metal is used in these. These are usually called warm edge spacers.

Frames are also an important feature of these windows. We have earlier discussed UPVC and composite frames which are the most common. In some cases frames can be wooden if your home is located in a conservation area where the original windows may have had wooden frames. Aluminium or steel frames are sometimes used as well.

The energy rating of your window is also important and is based on a grading scheme from A to G that measures the energy saving efficiency of the product. This is monitored by the British Fenestration Rating Council (BFRC). Visit BFRC for more information.

Ventilation within your home

If your home does not have adequate ventilation, this could also result in condensation and the formation of damp spots. As a general rule, homes with inadequate ventilation, heating or insulation will develop problems with mould and damp spots. If condensation starts to build up around the windows, there is a high possibility of your home having a damp problem.  If your home does not have much background ventilation, look for energy efficient windows that incorporate trickle vents to let in a controlled amount of ventilation. This is usually a small flap which can be turned up or down to let in air. Lastly, 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 replacing.

What should I do next?

Energy rating colour scale

So, if you’ve read this far, you probably realise that energy saving windows could be an integral part of a solution to save your energy costs, reduce your carbon footprint, reduce damp inside your home as well as eliminate unwanted noise pollution and screen out harmful solar radiation inside your home. The fact that there is a large choice in the market is both good and bad news. The good news is that you do have a choice between different brands, features, qualities and price points. The bad news is that much of this could be confusing when making a decision regarding the product and the installer.

So, the best strategy is to first read up as much information as you can on the subject to help you make an informed decision. Next, look for a vetted and reliable local service provider. The glass and glazing federation has a lot of useful information on their website to find a member who works in your area.  You also need to ensure that your new windows are fitted to the government’s building regulations standards. A person who can advise you on this can be found at the official competent person’s scheme. You can also contact your Perfect Crystal Windows representative to get free advice.

Happy hunting and hopefully you’ll have a warm and energy efficient winter.


Check our summer offers and get your discount code on our double glazed aluminium and uPVC windows before the end of August! Limited time only!


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