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To determine whether the benefits of triple glazed windows are worth their price, our experts have consulted trade organisations and top UK manufacturers to assess their triple glazed window options. We’ve done the research and present all the facts in this comprehensive guide so you can decide on the best options for your replacement windows.
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Triple glazed windows have three panes of glass – one more than double glazing. This makes homes cooler in the summer months and warmer in winter. Triple glazing units have excellent insulating properties thanks to the spacer bars included between each pane. The units are fully sealed, which creates a vacuum and prevents the build-up of condensation.
Triple glazed windows are often made from uPVC, which helps reduce heat loss. They’re also available in other materials, including aluminium and timber. Triple glazing is a versatile window choice with a broad range of designs available, including:
Window prices for triple glazing are from around £600 per window, depending on size, style and frame material – 10 to 20 per cent higher than for double glazing. This is because triple glazed windows are more complicated to manufacture and use around 30 per cent more materials than double glazing units.
The additional weight could require more manpower or specialised equipment to safely fit the windows, which increases labour costs, while structural work may need to be carried out to accommodate the thicker units. This all contributes to the higher triple glazing costs compared to 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 |
Triple glazed windows offer more benefits than drawbacks, particularly in energy efficiency, as they often result in lower energy bills.
Homes lose between 10 and 20 per cent of heat through their windows. Triple glazing offers superior thermal insulation, preventing heat loss and resulting in a warmer home. The lower U-value of triple glazing compared with double glazing creates a noticeable temperature difference. Triple glazing also has a lower G-value, reducing solar gain and preventing overheating in homes with many windows, particularly in south- and west-facing rooms.
| Glazing type | U-Value | G-Value |
|---|---|---|
| Triple glazing | 0.8 to 0.6 | 0.46 |
| Double glazing | 2.8 | 0.78 |
When shopping for a triple glazed window, look for:
Triple glazed windows often achieve A+ and A++ energy ratings, outperforming double glazing’s typical A rating. Their sealed design reduces drafts, condensation and cold spots, making homes less reliant on central heating. This leads to significant energy savings, potentially up to 50 per cent.
The L-value on sealed window units indicates how airtight their seals are. Lower L-values indicate better insulation and less heat loss at the window edges, contributing to the overall energy efficiency of triple glazed windows.
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 low. 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.
For homes in high-traffic areas, upgrading to double or triple glazing can significantly reduce noise levels, often by up to 40dB, especially compared to old single pane windows. The larger the gap between the panes, the better the sound insulation.
Each extra pane of toughened glass in triple glazing enhances security, making it much harder to break than single pane windows. Triple glazing often includes advanced safety features such as Secured by Design (SBD) locking mechanisms. The increased security also potentially adds to your home’s desirability and value.
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.
With the focus on higher energy performance certificate (EPC) ratings and reducing heating costs, triple glazed homes with ratings of A, B or C will likely become more desirable and increase in value.
Manufacturing triple glazed windows has a higher environmental cost due to increased CO2 emissions from producing the third pane and the need for heavier transport. However, a Glassonweb study shows that the CO2 savings over the lifetime of triple glazed windows outweigh emissions, with a carbon payback period of about 35 months in northern Europe.
“We love our triple glazing! Living on the busy A21, noise reduction was a big factor in getting triple glazing, and we can’t hear the traffic at all. The installation was quick and easy, and being uPVC, there’s no maintenance to worry about.
“Triple glazing has also made a huge difference in the comfort and temperature of the house – although it can get a bit warm sometimes.”
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If you’re considering whether triple glazed windows are worth investing in, it’s wise to consider the disadvantages as well.
Triple glazed windows typically cost 10 to 20 per cent more than double glazing due to their more complex design, the additional materials required in manufacturing and increased transport costs.
Installing triple glazed windows is more challenging than double glazed windows due to their increased weight and thickness, which require stronger frames and careful handling to avoid damage to walls. The process may take longer and need specialised tools, but experienced installers can ensure a smooth and secure installation.
Deciding whether to install triple glazing or double glazing depends on factors such as the location of your home, your energy-efficiency goals and your budget. You should 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 if you’d chosen double glazing.
| Double glazing | Triple glazing | |
|---|---|---|
| Energy-efficiency rating | B to A+ | A+ to A++ |
| U-value | 2.8 | 0.8 to 0.6 |
| G-value | 0.78 | 0.46 |
| Cost | From £525 | From £600 |
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, higher energy savings, better noise reduction and added security, but it comes with a higher initial cost and a longer carbon payback period than double glazing.
Triple glazing is a significant upgrade if you’re hoping to enhance your home’s comfort and energy efficiency, especially in colder environments where you can fully appreciate its benefits.
Triple glazing can increase the value of your home. Triple glazed windows make your property more energy efficient and lower your heating costs, which is something potential buyers will appreciate if you decide to sell it. The improved security and superior sound insulation 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 our trusted suppliers. Window installers often offer seasonal discounts or promotions on triple glazing if you’re already considering installing double glazed windows.
Yes, triple glazed windows can significantly reduce noise. The extra pane of glass and insulating air gaps provide better soundproofing compared to double glazing, making them effective for reducing external noise in a home.
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 to be durable, with uPVC windows lasting at least 15 to 20 years, while well-maintained wooden ones can exceed 60 years. Proper installation and regular maintenance as well as choosing reputable manufacturers and installers ensure maximum longevity and performance.
Triple glazed windows come in various colours, from classic white to modern anthracite grey and sage green. Dual-colour options are also available, allowing different hues inside and outside. Many manufacturers offer custom colour services to perfectly match your home’s exterior.
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, while decorative glass beautifies your property.
Triple glazing reduces condensation by providing better insulation, keeping the inner glass pane warmer and reducing the likelihood of moisture forming. This improved thermal efficiency helps maintain a consistent indoor temperature, which minimises the conditions that cause condensation.
The updated Part L Building Regulations, which took effect in June 2022, require replacement windows to have a maximum U-value of 1.6 or energy band rating of B for their window.
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.
