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Triple glazing windows are more than 30 per cent more energy efficient than double glazed windows and can halve heating bills. Additionally, triple glazing offers superior soundproofing and enhanced security. Poorly insulated windows can lead to significant heat loss, making triple glazing a good upgrade option when it comes to replacements.
To determine whether the benefits of triple glazing are worth their higher price, our experts have consulted trade organisations, spoken to top UK windows manufacturers, and assessed their triple glazed window options. Because we’ve done the hard research, presenting all the facts in this comprehensive guide, you can relax and make an informed decision regarding your replacement windows.
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Triple glazed windows have three panes of glass. Because that’s one more pane than is found in double glazing, triple glazed windows do a better job of keeping homes cool in the summer and warm in the winter. These windows have spacer bars between their panes, which further enhances their insulating properties. They are often made from uPVC, which helps prevent heat loss, though they are also available in other materials. Manufacturers ensure that the panes are fully sealed to prevent condensation.
Triple glazing is versatile and available in a wide range of window styles to suit various architectural and design preferences. Available styles include:
Window prices for triple glazing are about 10 per cent to 20 per cent higher than window prices for double glazing. That’s because triple glazed windows weigh more than double glazed windows do and are more complicated to manufacture. As a result, many installers only offer bespoke quotations for triple glazing and make the window units to order. Installation is also more complex. So, these additional triple glazing costs are not always part of the quote, which is not the case for double glazing.
| Window style and material | 600mm x 900mm | 900mm x 1,200mm | 1,200mm x 1,200mm |
|---|---|---|---|
| uPVC casement | £600 | £680 | £750 |
| Aluminium casement | £1,200 | £1,370 | £1,500 |
| Timber casement | £1,820 | £2,050 | £2,240 |
Combining triple glazing in colder rooms with double glazing in warmer rooms could be a great way to get the best of both worlds, while keeping costs down. For instance, double glazing would be a good addition to south- and west-facing rooms, which are prone to overheating. Triple glazing could be installed in north- and east-facing rooms, which can be chilly and have lower light levels.
Triple glazed windows have more pros than cons, especially when it comes to energy efficiency. There is some debate about how much more effective triple glazing is at combating noise pollution. But triple glazing is the clear winner at providing higher thermal efficiency, better security and reduced energy bills.
Thermal efficiency, which results in a warmer home, is one of triple glazing’s key benefits. Triple glazed windows have a much better U-value than double glazing, which results in an approximate temperature difference of two degrees. A U-value is a measure of thermal efficiency.
Triple glazing generally also has a lower G-value – which is a measure of solar gain – than double glazing. Solar gain can cause overheating in houses with a large number of windows. So, having a low G-value enables triple glazed windows to keep south- and west-facing rooms cool on hot days.
| Glazing type | U-Value | G-Value |
|---|---|---|
| Triple glazing | 0.8 to 0.6 | 0.46 |
| Double glazing | 2.8 | 0.78 |
Here are three things you should know about U-values:
Here are two things you should know about G-values:
When shopping for a triple glazed window, look for a low U-value to keep your home warmer in the winter and a low G-value to prevent your home from overheating in the summer.
Triple glazed windows typically score A+ and A++ on window energy-rating schemes. Their sealed design minimises draughts and condensation, and their thermal efficiency reduces cold spots in the home. By comparison, double glazed windows are usually A-rated.
Thanks to these factors, triple glazing makes households less reliant on central heating systems, which results in substantial savings on energy bills. Some window suppliers claim those savings could be as high as 50 per cent.
If you live in a high-traffic area and want to lower the noise levels inside your home, it’s a good idea to upgrade your windows. Both double and triple glazing offer improved soundproofing, particularly if you’re replacing old, poorly fitting single pane windows. The effectiveness of sound insulation generally increases with the size of the gap between the glass panes.
Each additional pane of toughened glass makes a window more robust and harder to break, meaning triple glazed windows are far more secure than single pane windows. Triple glazing is typically designed with enhanced safety features, such as Secured by Design (SBD) locking mechanisms.
SBD is a UK police initiative that promotes high security standards in building design and construction. The programme aims to reduce burglary and crime rates by incorporating crime-prevention techniques and security specifications. The products and projects it endorses meet stringent security criteria that are intended to ensure safer living environments.
There’s a high environmental cost for making triple glazed windows because of additional CO2 emissions from manufacturing the third pane of glass and heavier transportation weight for triple glazed units.
However, a Glassonweb.com study of residential glass installations found that CO2 savings over triple glazed windows’ lifetimes outweigh CO2 emissions during their production. The carbon payback period in northern European countries is around 35 months.
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As is the case with every home improvement product, triple glazing has some disadvantages. It’s wise to bear them in mind when you’re deciding whether triple glazed windows are worth the investment.
As we’ve mentioned, triple glazed windows usually cost at least 10 per cent to 20 per cent more than double glazed ones. The prices are higher because triple glazing is more technical in design and additional materials are used in the manufacturing process.
Because of triple glazed windows’ extra weight, there is a slightly higher chance of damaging walls during the installation process. But this shouldn’t be an issue with a high-quality professional installer or supplier.
Choosing between triple glazing and double glazing is a big decision. A lot depends on where your home is located, what your energy-efficiency needs are, and your budget. It’s important to assess quotes from both triple and double glazing suppliers and weigh your options carefully.
Although the initial cost of triple glazing may be higher, it’s likely worth it in the long run. Your home will have a lower carbon footprint, and your energy bills will be cheaper than they would be if you had chosen double glazing.
| Double glazing | Triple glazing | |
|---|---|---|
| Energy rating | A+ | A++ |
| Warmer home (lower U-value) | ✓ | ✓✓✓ |
| Prevents overheating(lower G-value) | ✓✓ | ✓✓✓✓ |
| Price | ££ | £££ |
To decide if triple glazing is worth it for your home, use our quote form to obtain quotes on both triple and double glazed units in the same styles and materials.
Triple glazing offers superior insulation, energy savings, noise reduction, and added security but comes with a higher initial cost, and a longer payback period than double glazing.
Triple glazing is a significant upgrade for enhancing home comfort and energy efficiency, especially in colder environments where its benefits are fully realised.
Triple glazing can definitely add value to your home. Triple glazed windows make your property more energy efficient and lower your heating costs, which is something potential purchasers will appreciate if you decide to sell it. The improved security and superior sound insulation that triple glazing offers also add to your home’s overall comfort and increase its resale value.
To find the best deals on triple glazing, fill out our quote form and compare quotes from several of our trusted suppliers. They often offer seasonal discounts or promotions on triple glazing if you’re already considering installing double glazed windows.
There are no specific triple glazed windows grants. But you can apply to other government schemes that may enable you to boost your home’s energy efficiency with other home improvements, such as window installations and upgrades.
Triple glazed windows are designed for durability, typically lasting 20 to 35 years depending on the material. uPVC windows last 15 to 20 years, while well-maintained wooden ones can last up to 60 years or more. Proper installation, regular cleaning, sealant repair, and maintaining frame condition can extend their lifespan. Investing in windows from reputable manufacturers and professional installers ensures optimal performance and longevity.
Yes, triple glazed windows are available in a wide range of colours, so you can choose options that harmonise with your home’s exterior colour scheme and enhance its appearance. The choices include traditional white windows, contemporary anthracite grey windows and sage green windows. There are even dual colour options with frames that are one hue on your home’s exterior and another inside your rooms. Manufacturers often offer custom colour services that allow you to achieve the exact look you desire.
Triple glazed windows can be fitted with various types of glass to meet different needs. Low-emissivity glass minimises heat loss, toughened safety glass offers added security and noise-reducing acoustic glass reduces sound transmission.
Additionally, self-cleaning glass uses sunlight and rain to keep windows clear, and decorative glass beautifies your property.
The Part L Building Regulations, which took effect in June 2022, dictates replacement windows must have a maximum U-value of B for their window energy rating.
In January 2023, the Scottish government announced plans to introduce a standard for all new build housing to meet an equivalent of the Passivhaus standard. The official report doesn’t specify what the Scottish standards are. However, Passivhaus builds often use triple glazing to achieve the low U-values required for certification.
