Installing triple-glazed glass is an excellent way to make your home or workplace more energy efficient and comfortable. The superior level of insulation in these windows can help reduces both heat loss and noise transmission. These advantages make them a better alternative to the standard UPVC or double-glazed windows.

But what does actually triple glazing mean and why it is better than double glazing? In this article, we'll give you more detail about triple-glazed glass, its composition and how it differs from the other types of glass. We will also look at the benefits of these windows and why they are worth considering for your next building project.

What is triple glazing?

Triple glazing is a type of window glass that, as the name implies, is made up of three panes of glass. The panes or layers are separated by two air spaces, which are typically filled with argon or krypton gas. Because this gas is heavier than air, it acts as a protective barrier, improving the insulating properties of the glass. As a result, triple-glazed windows offer better energy performance and noise reduction than double-glazed windows, which have just two panes of glass.

Triple glazed glass can be a great option for homeowners or business owners looking to reduce heat loss from a building and lower heating costs. They might also be a perfect solution for those who live near busy thoroughfares or in noisy areas. The additional pane of glass can help minimize noise pollution from the outside, making the interior of the building quieter and more comfortable.

How does triple glazing work?

Triple-glazed windows and skylights act as an insulator between the inside and outside of a building. The 3 panes of glass create an insulating barrier which prevents the loss of heat. The gas which sits in the air spaces between the glass layers further increases the insulating properties of the unit. 

It is normal for your home to lose some heat through the windows and doors. Some windows, however, transmit more heat than others. Single-pane windows, for example, can allow more heat to escape. The same is true for older, inefficiently insulated windows.

Thermal transmittance, also known as U-value, is a measure of how much heat can pass through a window. The lower the U-value of a window, the more effective it is at retaining heat inside the property. Thermal transmittance in single glazed windows is around 5.0 - 6.0 W/m²K while in double-glazed windows it ranges from 3.0 to 1.0 W/m²K. The centre pane U-value of triple glazing can be as low as 0.6 W/(m²K), resulting in exceptional thermal efficiency.

The two air spaces between the glass layers in a triple-glazed window form a barrier that can reduce heat loss and gain through the window. This helps keep your home warm in the wintertime and cool during the summer months. Additionally, the frame of the triple glazed unit is usually made of aluminium. This is a durable and strong material with good thermal conductivity, which can further reduce heat loss and enhance energy efficiency.

The barrier that is created by these windows not only helps to provide better thermal performance but also to reduce noise pollution. The multiple layers of glass and air spaces between them help block the noise that may come from the outside.

Feel free to take a look at our triple-glzed flat roof windows and skylights.

Double glazing vs triple glazing: What is the difference?

Both double and triple glazed windows are effective in enhancing energy efficiency, minimizing noise transmission, and improving comfort in homes and commercial buildings. However, they are two different types of windows, with different levels of insulation.

Here are some of the main differences between double glazing and triple glazing.

  • The number of glass panes used. One of the primary differences between both types of windows is that triple glazing consists of three panes of glass whereas double glazing has two. 
  • The number of insulation pockets. The three layers of glass in triple glazed windows are separated by two air spaces, while double glazed units consist of only one insulating pocket.
  • U-values and energy efficiency. The triple glazed window has a thermal transmittance or u-value of 0.6 W/(m²K) whereas the windows with two glass panes offer a u-value of around 3.0 to 1.0 W/m²K. Consequently, triple glazing provides better heat insulation than double glazing and is therefore more energy efficient.
  • Noise reduction.  Due to the additional glass pane and insulating pocket, the triple glazed windows can significantly limit the noise coming from the outside.
  • Costs. Compared with double glazed windows, triple glazed windows provide more insulation and efficiency, but they are also more expensive.

Overall, triple glazing provides numerous benefits, and while it is typically more expensive than other types of windows, the long-term savings on energy bills and other advantages may make it a worthwhile investment for homeowners or builders.

You can read more about the differences between acoustic glass, triple and double glazing.

What are the benefits of triple glazing?

Triple glazed glass offers a number of advantages over a double and single pane of glass, including:

  • Enhanced energy-efficiency. Triple glazing is one of the most energy-efficient types of glazing on the market. It has three panes of glass separated by two insulating layers of gas or air. This significantly reduces heat loss through the window, resulting in lower energy bills.
  • Better noise insulation. The extra pane of glass and air space in triple glazing aid in preventing noise transmission from outside to inside the building. This is especially useful in areas with a lot of traffic or other noise pollution.
  • Improved security. Triple glazed windows are more difficult to break since they have an additional glass pane. This can be particularly beneficial if you live on a lower floor because it provides a stronger barrier against intruders.
  • Greater level of comfort. Triple glazed glass can eliminate cold drafts and reduce temperature variations between rooms, making homes more comfortable and cosy. In addition, these types of windows are less prone to condensation. The extra glass pane and insulating pocket help to maintain a more consistent temperature on the interior surface of the window, reducing the risk of moisture buildup.
  • Increased home's value. Installing triple glazing can increase the value of your property. These windows are regarded as a high-end feature that can improve a home's energy efficiency and comfort while also reducing noise pollution. This can make the property more appealing to potential buyers or renters while also increasing its value.

Additionally, by choosing triple-glazed sealed units with a low-emissivity coating on the glass (Low-E), you can further enhance the energy efficiency of your property as well as lower your heating costs.

What are the disadvantages of triple glazing?

Triple-glazed windows have numerous benefits over other types of glazing. However, there is one significant trade-off to consider when installing such windows on your property. The main disadvantage of triple glazing is that it is ab expensive investment, which is often an impediment for some building owners. However, the higher initial cost may be offset in the long run by potential energy savings and increased comfort.

Another thing that might be considered a drawback of triple glazed windows is that they are heavier than double glazed units due to the extra glass pane and insulation, which can make them more difficult to install. Additionally, modifications to the window frame or wall opening may be required during the installation process to accommodate the larger size and weight of the triple glazed windows.

Professional window installers have the knowledge and equipment to safely and efficiently install triple glazing units, ensuring that the new windows are properly sealed and aligned for maximum energy efficiency and performance. They may also offer warranties or guarantees on their work, giving you peace of mind that your investment is protected.

Is triple glazing worth it?

If you want a thermally efficient home that doesn't let heat escape, triple glazing would be the best option. These windows would be particularly beneficial for regions with cold or hot climates. They can retain heat in your home during the colder months and reduce the amount of heat that can enter in hot summers. Installing triple glazing is a great way to reduce your energy bills. 

These windows might be also a perfect solution in case your property is located in an area with high levels of noise pollution, such as near busy roads, railways, or airports. They can help to reduce noise from outside improving the comfort of your home.

Overall, when deciding whether to upgrade to triple glazing, you should consider many factors such as the climate, the condition of the existing windows, energy efficiency, and comfort. Other important things that must be looked out for include Window Energy Rating (WER), building regulations, sound pollution and cost.

In general, triple glazing is worth it if you are seeking a thermally efficient home, reduced energy bills, and improved noise insulation. These windows are especially beneficial in regions with extreme hot or cold climates and areas with high levels of noise pollution. While triple glazing is more expensive than double glazing, the long-term savings on energy bills and increased comfort may offset the higher initial cost.

It is best to consult with professional window installers to evaluate your home and priorities and help you make the best choice.

Frequently asked questions

How thick should triple glazed windows be?

The thickness of triple glazed windows can vary between 28mm to 44mm depending on the specific design and materials used. In general, the outer glass panes are thicker than the middle panes to provide additional impact protection and better insulation. Each pane's thickness can range from 3mm to 10mm, for a total thickness of 28mm to 44mm for the entire triple glazed unit.

If you are considering replacing your windows or building a new house it might be best to choose triple glazing with a minimum overall unit thickness of 36mm. To achieve greater energy efficiency and well insulated home, you may want to opt for a window with a Low e coating, Argon cavity gas and warm edge spacers used to join the glass panes together. 

Triple glazed windows can have several features that make them more energy-efficient, secure, and durable. You may opt for Low-E windows, low iron glass, gas filled units, toughened triple glazed units and so on. It is always best to consult with professional installers to help you choose the best triple glazed products for you.

What is triple Low-E glass?

Low-E glass is a type of triple glazed window with three panes of glass covered with low-emissivity (Low-E) coatings. Low-E is a microscopically thin coating that is applied to the surface of glass to reduce energy loss through the window. This helps to keep your home warmer during winter and cooler in the hotter months. 

How long does triple glazing last?

The lifespan of triple glazed windows depends on several factors, including the quality of the materials used, the installation process, and the level of maintenance they receive. With proper care and maintenance, triple glazed windows can last for 20 to 30 years or more.

Does triple glazing stop condensation?

Triple glazing can help reduce condensation by providing better insulation and maintaining a more consistent interior surface temperature on the window. However, it does not completely eliminate condensation. Internal condensation is not directly caused by double or triple glazing, but new windows may sometimes exacerbate condensation issues by reducing draughts. To effectively minimize condensation, proper ventilation and heating are necessary to vent moisture-laden air to the outside and keep surfaces above the dew point temperature.