Everything You Need to Know About Double Pane Glass

As the world continues to focus on sustainable living, making energy-efficient home upgrades has become a priority for homeowners. And one of the most effective ways to improve a home’s energy efficiency is by upgrading to double-pane glass windows.

These windows can significantly reduce energy consumption. Moreover, they can also help homeowners contribute to environmental conservation by minimizing carbon footprints.

So, if you're considering this home upgrade but want to learn more about what makes double-pane glass worth the investment, read on!

Key Takeaways

• Double pane glass features two glass layers with insulating gas in between. An Insulated Glass Unit also contains a spacer, a desiccant substance, and a sealant. The glass can also incorporate Low-E coatings.
• Benefits of double pane windows include superior insulation, notable energy cost savings, noise reduction, and an increase in property market value due to their energy-efficient design.
• Choosing the right glass thickness, gas type, and advanced spacer technology is crucial for optimizing insulation and overall performance of double pane windows.

What Is Double-Pane Glass?

The term double-pane glass refers to an Insulated Glass Unit (IGU) that consists of two layers of glass separated by a space filled with air or inert gas. The IGU is then fixed within the window sash and frame.

Besides the gas, the two window glass panes are separated by a spacer. This component is typically made from malleable materials that allow it to expand and contract along with movement in the glass unit. This further improves the window's energy efficiency. The desiccant is also part of an Insulated Glass Unit. Its goal is to absorb any moisture that enters the insulated space. Last but not least, the glass can have a Low-E coating.

This construction creates an effective thermal barrier that reduces heat transfer. Consequently, you’ll depend less on artificial heating and cooling, which translates into energy savings.

In the following sections, we will discuss all these components in detail.

Insulating Gas

As mentioned earlier, the space between the two panes within a window unit is separated by an inert gas. Occasionally, that space is filled with air, but the window does not have the same degree of energy efficiency in this case.

The most commonly used inert gas is argon gas. It is colorless, odorless, and tasteless. Its thermal conductivity is 67% that of air, and it is six times more dense than air, which is why it's an excellent insulator.

Another type of inert gas is krypton gas. It is a naturally-occurring odorless and colorless gas. Krypton insulates much better than argon. However, it is also 40% more expensive than argon. This is why krypton gas is only rarely used in the window industry. It may be preferred for windows that require thin gaps between the two panes of glass.

Xenon gas has the best insulating properties, which is why it is also extremely expensive. This gas is used only for structures with extensive glazing, such as skyscrapers.

Spacer and Sealant

The spacer is basically a strip of material that separates and supports two glass panes within an Insulated Glass Unit. It is usually made of plastic, metal, or foam. The spacer is fixed within the window unit with a sealant that prevents it from moving and reduces condensation. The spacer and the sealant create an airtight cavity, preventing gas leaks.

There are three types of spacers:

• Non-metallic spacers, which are made of rubber or foam; they are highly efficient in blocking heat transfer and reducing condensation; they expand and contract along with the panes.
• Warm-edge spacers, which combine metallic and non-metallic materials and thus prevent heat and cold from passing through the window unit.
• Metal spacers, which are the least efficient because they allow heat and cold to pass through the window unit.

Desiccant

Have you ever seen a double-glazed window with condensation between panes? This should not happen unless the window is old and/or of low quality or the seal is broken.

However, this doesn't mean that the space between the two glass panes is completely moisture-proof. A window undergoes a daily process of thermal exchange. This can let some outside air enter the space between the panes. If it weren't for the desiccant, that moisture would remain trapped within that space, and gas would leak. As such, the desiccant is a super-absorbent material that absorbs excess moisture and maintains the window's insulation.

Low-E Coatings

Double-pane glass is energy-efficient by itself. However, you can make it even more energy-efficient by adding Low-E (low emissivity) coatings. In this case, the glass is often called Low-E glass.

A Low-E coating is a thin, almost transparent coating that is applied directly to the glass. Because it is invisible to the naked eye, it doesn't affect how much visible light passes through the window. This advanced coating reflects heat back into the house during the winter. It rejects the sun's heat and UV rays during the summer. This dual action maintains a comfortable indoor climate and further reduces energy consumption.

However, Low-E coatings can be applied to different glass surfaces. For maximum efficiency, the surface needs to be chosen wisely, depending on the climate.

Glass Thickness

Window glass typically measures between 3 mm (1/8 in) and 6 mm (1/4 in), although some are much thicker. For example, tempered glass is typically 4.8 mm (0.18 in) thick, while frosted glass can reach a thickness of 19 mm (0.74 in).

Nonetheless, this is not the thickness of an Insulated Glass Unit because it has two glass panes. Instead, an IGU usually has a total thickness ranging between 20 mm (0.78 in) and 28 mm (1.1 in).

It's important to keep in mind that the larger the gap between the two glass panels, the more energy-efficient the window unit is. Magic windows, for example, have a 1-inch (25.4 mm) gap between the two glass panes, which is why they are more energy-efficient than other products on the market.

Moreover, you can also opt for thicker glass if you want superior insulation and noise reduction. You can discuss this with the window company you've chosen.

Benefits of Double Pane Glass

One of the most compelling benefits is that double-pane windows provide significant energy savings. You will not have to rely on heating and cooling systems too much if you decide to replace your windows. Besides this, you also contribute to environmental efforts thanks to the fact that energy-efficient windows reduce carbon footprint.

Another major advantage is superior noise reduction. Double-glazed windows are highly effective at minimizing outside noise, so they help create a quieter and more serene indoor environment. Most homeowners are really happy with double-pane glass from this point of view after switching to it from single-pane glass.

Furthermore, dual-pane windows reduce window condensation during cold weather. If you've ever had single-pane windows, you probably know all too well how easily condensation forms on them when it's cold outside. This happens because the glass surface gets very cold. This issue is almost completely eliminated with double-pane windows. This also translates into a lower risk of mold growth.

Last but not least, double-pane windows can significantly increase your property’s market value. Nowadays, energy efficiency has become a priority, so potential buyers are often willing to invest more in environmentally-friendly homes. You can also apply for rebates and incentives if you decide to install dual-pane windows. They can make your investment much more manageable. However, keep in mind that your windows need to be ENERGY STAR-certified if you want to apply for these programs.

Installation Process for Double-Glazed Windows

If you plan to install double-glazed windows, we recommend investing in professional installation. Given that this is quite a significant investment, it's best to make sure the windows are installed correctly from the very beginning. If the window is not aligned or insulated properly, this can lead to air and water leaks, which can damage your brand-new windows in no time.

Most window companies offer installation services. In this case, the installation may be covered by the warranty as well. This means that if your windows were to develop issues because of a faulty installation, the warranty would cover the repairs. Ultimately, it's best to discuss these details with the window company before buying the windows.

Maintenance Tips for Longevity

Like any other window, double-pane windows require regular maintenance. This includes cleaning the glass and window frame and lubricating the hardware regularly.

It's especially important to check the seals periodically, looking for sealant cracks or gaps. If you notice any issues, it's of the essence to address them right away to prevent further damage. Once you see condensation between panes, you may be dealing with seal failure, in which case your windows are likely already beyond repair and need to be replaced. You may be able to replace just the Insulated Glass Unit if the frame is in good condition.

Double Pane vs. Single Pane vs. Triple Pane

It goes without saying double pane windows are much more energy efficient than single-pane windows. In fact, single-pane units are only rarely installed nowadays. Dual pane windows have pretty much become the industry standard, especially in regions like the GTA.

Naturally, triple-pane windows are more energy-efficient than double-pane windows. They have three panes of glass and two spaces filled with inert gas. Plus, they can also have more Low-E coatings. However, all these additions translate into higher prices, which is why homeowners are often reluctant to install triple-pane windows and justifiably so. Even though triple-glazed windows offer greater insulation and energy savings, they may not be necessary for all climates. These windows are typically recommended for regions in Northern Canada where superior insulation is required.

Houses in the GTA can benefit from Magic's thermal blind technology coupled with our double-glazed units. Our blinds are made from an insulating material that considerably improves energy efficiency, equaling the insulating properties of triple-pane windows!

Find the Most Energy-Efficient Double-Pane Windows at Magic!

At Magic, we prioritize your comfort and your home's energy efficiency. Since we've brought glass production in-house, we can use materials of the highest quality within our Insulated Glass Units and deliver custom-cut glass that fits various window sizes and shapes. This translates into superior energy efficiency, noise reduction, and comfort. So, if you're looking for replacement windows, give us a call and see the magic for yourself!

Frequently Asked Questions

What does double pane glass do?

Double-pane glass creates a thermal barrier that minimizes heat transfer, thus helping reduce heating and cooling costs. Windows with two glass panes also have a space filled with inert gas that further improves its energy efficiency.

How to tell if the glass is single or double pane?

You can tell if the glass is single or double pane by looking at the inside glass edge. If it's a window with two glass panes, you should be able to see a small gap and a spacer separating the panes.

Can you replace just the glass in a double-pane window?

You can replace just the glass in a double-pane window, which means you'll be replacing the entire Insulated Glass Unit. This is usually recommended only if the window frame is in good condition.

Is double-pane glass expensive?

Double-pane glass is more expensive than single-pane glass, so it can be a significant investment, depending on the materials and window size. However, you can apply for rebates and government incentives that can lower the cost of this energy-efficient upgrade.

What is the lifespan of a double-pane window?

A double-pane window has a lifespan of approximately 20-40 years. But this depends on its quality, how well it is maintained, and the climate.

What types of gases are used in double-pane windows for insulation?

Double pane windows commonly use argon and krypton gases for insulation, with argon being the most cost-effective option and krypton offering superior thermal performance.

How does glass thickness impact the performance of double-pane windows?

Glass thickness significantly impacts the performance of double-pane windows by enhancing durability and insulation properties. It is crucial to choose the appropriate thickness based on the local climate to optimize energy efficiency.

Why is professional installation important for double-pane windows?

Professional installation is crucial for double-pane windows as it guarantees a proper fit, which minimizes air leaks and enhances both energy efficiency and the longevity of the windows.