The Different Types of Glazing

Single Glazing

Single glazing is the most basic window option. As the name suggests, it consists of a single pane of glass. Due to its poor thermal and acoustic insulation properties, single glazing is now rarely used in new construction projects.

This type of glazing can still be found in wood products, particularly from manufacturers specializing in heritage or traditional windows, such as Belisle Architectural Doors and Windows.

Double Glazing with Low-E Argon

Available in double-pane insulated glass units, this option is highly popular thanks to its strong thermal performance while remaining affordable. It consists of two panes of glass separated by a low-conductivity spacer. The sealed unit is filled with an inert gas—typically argon—which significantly reduces heat loss in winter and limits excessive heat gain in summer.

For even higher performance, a low-emissivity (Low-E) coating is added. This ultra-thin metallic layer further reduces heat transfer and minimizes UV radiation, helping protect furniture and fabrics from fading while improving overall energy efficiency.

Triple Glazing

Triple glazing is made up of three panes of glass separated by two layers of inert gas. It provides superior thermal insulation, offering up to 40% better performance than double glazing. It also limits heat gain, which can be beneficial in hot weather but less advantageous in colder conditions. While extremely effective at reducing thermal exchange, triple glazing slightly reduces natural light transmission. Its acoustic insulation performance, however, is comparable to that of double glazing.

Triple glazing is particularly well suited for Passive House projects, helping meet the stringent requirements of the Passivhaus standard. This is the technology Isothermic adopted in developing its Series 2, a product line that is unmatched on the North American market.

Due to its increased weight, installing triple glazing can be more complex. At Isothermic, we strongly recommend using our certified installation services to ensure optimal performance. Even the highest-quality window can lose its effectiveness if improperly installed. When investing in premium products, professional installation is highly recommended.

Other Factors That Influence Performance

The number of glass panes is not the only factor to consider when selecting high-performance glazing. A customized configuration—tailored to your region and specific needs—can be developed with your Isothermic advisor. Key elements to consider include:

• Glass thickness
• Spacing between panes
• Laminated glass options
• Solar control glazing
• Low-E coatings

Conclusion

In summary, choosing the right glazing requires careful consideration of your specific needs in terms of thermal comfort, sound insulation, and security. While double glazing offers an excellent balance between performance and cost, triple glazing stands out as the optimal solution for passive homes or for homeowners looking to maximize energy efficiency. Regardless of your choice, professional installation—such as that offered by Isothermic—is essential to ensure your windows perform at their best.