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Can Double Glazing Help Reduce Heating Bills?

(3 min read)

Yes, double glazing can definitely help save on heating bills by reducing the amount of indoor heat that escapes through the windows.

Quick FAQs

Can double glazing help reduce heating bills?

Yes. Double glazing can definitely help save on heating bills by reducing heat loss and increasing solar absorption.

Is double glazing better than secondary glazing?

Yes, in most cases, but there can be cases where it's not viable, such as listed property restrictions.

Is triple glazing better than double glazing?

Yes, up to 40% better energy efficiency, but additional costs need to be taken into consideration.

Keep reading to find out more about the benefits of double glazing and how to reduce your heating bills by keeping your home warm for less. 

How Does Double Glazing Work To Reduce Energy Loss?

A double-glazed window is a sealed window unit that has two panes of glass with a gap between them (known as the “spacer”). The size of the spacer is important in the overall insulation, as is the quality of the glass and the quality of the overall unit.

In contrast to double glazing, single glazing has just one pane. This single pane is in direct contact with both environments, therefore lacking the critical thermal property of only exposing each pane to one of the two environments.

Obviously, there’s more to it than just having two panes of glass with a gap between them.

The two panes of glass form a pressure-sealed unit. The gap between them is typically filled with Argon gas, which is a poor heat (and sound) conductor, meaning it’s harder for temperature (and sound) from one environment to travel through to the other side. The gap is normally around 16-20mm.

In addition the window frame’s material also plays its part.

  • uPVC – energy saving multi-chambered uPVC window units
  • aluminium – energy saving aluminium windows with thermal breaks
  • timber – naturally insulating timber window units

These ingenious constructions are very effective and typically reduces heat loss by around 40-50% or more over single-glazed windows.

What Are the Energy Ratings for Double Glazing?

The energy efficiency rating of double-glazed windows is measured using the Window Energy Rating (WER) system. The energy rating ranges from A++ to G, with A++ being the highest.

Key performance criteria for energy ratings

The window’s rating is calculated by measuring how sufficiently it:

  1. Controls heat loss
    U value – thermal transmittance. Measures heat retention. The lower the U value the better.
  2. Absorbs the sun’s energy
    G factor – solar energy. Measures heat capture. Ranges from 0-1, the higher the better.
  3. Keeps out drafts
    L factor – air leakage. Measure air-tightness. The lower the L factor the better.

The better the combined factors the better rating the unit will achieve.

Read more about our energy efficiency ratings here.

What Different Types of Double-glazing Windows Are Available?

Double-glazed windows come in various different materials and styles. All are sealed units.

Window unit materials

The four main types of double-glazing units are:

Window unit styles

There are many styles of double-glazed windows on the market, which include:

The type of windows you choose comes down to your own preferences, budget and the type of property they are for. You can also use our online pricing tool to help with the options.

What’s the Verdict?

Investing in energy-efficient double-glazed windows (and doors) will help keep you reduce your heating bills by trapping more warm air in and absorbing more solar energy. If you’re looking to replace your windows, take a look at our wide range of A-rated double-glazed windows, that offer great security and noise reduction levels, too.

Try our online pricing tool to get an instant guide price in minutes and check out our special offers. 

For even higher energy performance take a look at our triple-glazed windows.

Call or email the glazing team and they’ll help you take the first steps towards boosting your home’s energy efficiency.

Need advice?

Talk to one of our glazing experts to find out more about energy efficient windows.

Talk to an Expert

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Paul Wallis
Paul Wallis
We recently decided to replace our front door, and could not be happier with the result! Thanks so much to Kate, for her time and understanding. Cannot say enough good things about the installation, and Cameron was tidy and efficient. It's been a pleasure to work with Three Counties recently, doors and windows. Many thanks!
Danielle Horsley
Danielle Horsley
Lovely looking door
Agatha W
Agatha W
Three Counties have been superb, their customer service is great and their workman were polite, cleaned up after themselves and the workmanship is excellent!! I am very pleased with their work and would happily recommend them.
Tom Winter
Tom Winter
Excellent service!! We had 21 windows and 3 doors installed and very happy with it all. The process from start to finish was stress free and Ron and Lee who installed the windows and doors were great. Would definitely recommend!
Phil Redhead
Phil Redhead
Just had my tatty old windows replaced by Three Counties, and it’s been a highly professional job from start to finish. Communication from the administration team was prompt and courteous at all times, and installation ended up being much quicker than advertised projections. Installation was without issue and the lads who did the work were amenable to my requirements and did an excellent job. Very happy with the entire process. Three Counties were recommended to me by friends and I can certainly now recommend them to others.
Mark Boyce
Mark Boyce
Bought two new windows and a new front door from Three Counties, was very impressed with the attitude of all staff, who were friendly and informative. Price was good, and installation completed without a hitch - very happy with the final product, and would definitely use again.
Paul Picknett
Paul Picknett
We have just had all our windows (18) replaced, french doors (20 and side panels (2) by Three Counties. We could not be more pleased with their workmanship and the finished product. They left the property incredibly clean after each day, and this despite the messy nature of ripping out old windows and frames. We were kept informed at each stage and a minor snagging issue was resolved promptly and efficiently after installation. A first class service. We would not hesitate to recommend Three Counties.
Anna Trevelyan
Anna Trevelyan
Three Counties have now installed several windows and doors on our house and they're always my go-to company. I used another before I discovered them and they let me down, but I absolutely cannot fault Three Counties. From the moment you contact them they're courteous and professional, and they keep in touch with timescales and installation times. Friendly installers too, who go above and beyond. You'd think all this great service would cost more but they beat other companies on price. Highly recommended and trusted, I'd never go anywhere else now.