Nowadays, double glazing is the window equipment in the spotlight. Of quality, it is automatically used for a new construction and for a renovation. If triple glazing is more and more widespread, it still struggles to compete with this monopoly.
Installing a triple-glazed window can, however, have a definite advantage, particularly for so-called passive houses. What are the advantages ? What are its disadvantages? What does it consist on ? When and where is it recommended? What budget should you consider? Our experts tell you all about triple glazing!
What is triple glazing?
As the name suggests, triple glazing is made up of three layers of glass, each 4-6mm thick, between which argon gas or krypton gas – more insulating than air – acts as insulators , on a thickness of 12 to 16 mm, called blade. More insulating than double glazing, it has a heat loss coefficient for glazing alone (Ug) of approximately 0.7 W/m²K, which represents a nearly 40% improvement in performance. This score allows it to be particularly effective in cold regions. However, it offers sound insulation substantially comparable, or even less, to that of double glazing.
The other aspect of triple glazing is that its additional glass helps reduce the heat gain in the home. As an illustration, its g factor is around 0.5, compared to 0.65 on average for double glazing, i.e. nearly 25% less. The g factor is the proportion of solar energy returned to the heart of the house. In addition, it limits the penetration of light into the home, its light transmission coefficient (TI) being 0.7, i.e. almost 12.5% less than double glazing.
In addition, triple glazing is 50% heavier than double glazing, with a weight of 30 kg/m². The window joinery must therefore be stronger and of better quality. As a result, triple glazing is not suitable for home renovation work. Also be aware that it is more difficult to handle during installation.
When to choose triple glazing for a window?
A house that is poorly insulated and equipped with single-glazed windows loses an average of 20% of its heat. Be aware, however, that installing triple-glazed windows will not significantly reduce this loss if your home has only low or average insulation. Before the installation of triple glazing, it is necessary to carry out an energy balance in order to ascertain the usefulness or uselessness of the installation. Indeed, it is not wise to invest in a window that is expensive and consumes more raw material if the gain is low (about twenty euros per year according to the studies carried out), or even zero.
On the other hand, triple glazing is particularly effective in low-consumption housing, so-called passive and ecological houses and homes with very high energy performance, because it contributes to a significant and lasting reduction in energy expenditure. In this case, it makes it possible to significantly reduce the heating, or even to dispense with it completely.
However, triple glazing is not suitable for all homes. It is only recommended in cold regions, on facades exposed to the north and with little sunlight.
What are the advantages of triple glazing?
To better assist you in choosing your glazing, here is a presentation of the main advantages, but also the disadvantages, of triple glazing.
The benefits of triple glazing
- It offers excellent thermal insulation, resulting in very low heat loss.
- Its quality makes it possible to greatly reduce the use of heating in winter (for passive houses only), or even not to need it at all, because the house retains the heat produced and/or perceived.
- Its thickness and low heat absorption provide you with pleasant comfort during periods of high heat.
- Its quality insulation allows you to make significant energy savings each year, and therefore your bill!
The disadvantages of triple glazing
- Its very heavy glass, around 30 kg per m² (against 20 kg per m² for double glazing) is difficult to handle.
- To be installed, it is essential that your joinery and your hinges are solid. Otherwise, the entire installation will have to be changed, which entails a substantial additional cost.
- Its acoustic insulation is substantially the same as that of double glazing, or even of lower quality.
- It retransmits only a smaller part of daylight; an advantage in summer, but a source of discomfort in winter!
- It is more expensive to purchase than double glazing, around 50 to 80%!
What budget should I plan for a triple-glazed window?
Compared to double glazing, a triple-glazed window of the same size will cost you on average 50-80% more. This type of project is therefore thoughtful, because it is a substantial investment for windows whose lifespan is around thirty years.
Thus, for a triple-glazed window, count at least 600 euros, installation included; but the cost can reach or even exceed 3,000 euros! Indeed, the price of this type of insulating window depends on several criteria:
- Window size (glass surface, standard or custom)
- The type of carpentry (wood, PVC, aluminum)
- The technology used (type of gas, glass treatments, coating, etc.)
- The possible change of the carpentry if yours proves to be too weak
- The number of windows to install
- The selling price of the equipment charged by the seller
- The labor rate charged by the service provider for the installation
If you have an ecological habitat or a passive house, this investment will quickly pay for itself thanks to the reduction in your energy bill.
Thus, if the price of a single window varies between 100 euros and 500 euros per m², the installation of a single window by a professional can reach 500 euros due to the difficulty of the installation and the heaviness of the glass. . However, it is essential to call on a professional to install your triple-glazed windows, otherwise you risk losing out! Indeed, the slightest defect considerably reduces the benefits of this type of glazing in terms of performance.
Do not hesitate to make several free window estimates and compare them both for the work and the prices of the craftsmen and for the quality of the triple glazing offered. Preferably choose an RGE Qualibat craftsman, that is to say Recognized guarantor of the environment. It is a guarantee of quality, because a qualified craftsman is regularly checked. A good professional will come to your home to study the possibilities available to you; he will not try to sell you useless equipment and he will be able to advise you on the openings to be equipped with triple glazing.
You have every right to ask to visit sites carried out by the craftsmen you meet, it’s a good way to get feedback from customers and see the quality of a service. Finally, the craftsman you have selected will be obliged to provide you with a ten-year insurance certificate, this being intended to cover the work carried out in the event of a hidden defect. Make the request in order to be well protected.
You now know everything about triple-glazed windows. Are you ready to get started?