Window Film Blog
Photo of a cross section of a double pane window

What is a Double Pane Window

One of the most popular types of windows on the market is the double pane window, known for its energy efficiency and insulating capabilities. If you are considering installing window film, it’s important to know what kind of windows you have to make sure you are choosing a compatible film. So, let’s look at what a double pane window is and how it works.

The Anatomy of a Double Pane Window

Double pane windows, also known as dual pane, double-glazed, or insulated glass windows, are essentially composed of two glass panes separated by a gap filled with air or inert gas like argon. The gap serves as an insulator, reducing the transfer of heat and cold between the interior and exterior environments. This creates a barrier that keeps your home warm in the winter and cool in the summer.

Here are some technical aspects that distinguish double pane windows:

The Glass Panes

Each pane in a double pane window is typically made of clear glass, although low-emissivity (Low-E) coated glass is also a popular option. Low-E coatings help to minimize the amount of ultraviolet and infrared light that can pass through glass without affecting the amount of visible light.

Below is a diagram that compares a single pane window to a double pane:

Illustration showing the difference between double pane and single pane windows


The spacer, made of metal or a less conductive material like foam, separates the two glass panes and creates a sealed air or gas-filled space. The spacer often contains a desiccant material that absorbs moisture to prevent fogging between the panes.

Gas Fill

Inert gases like argon or krypton are usually used to fill the gap between the panes. These gases are non-toxic, odorless, and have higher insulative properties than air, thereby improving the window’s thermal efficiency.


To ensure that the gap remains airtight and moisture-free, the whole assembly is sealed using sealants like silicone or polyisobutylene. A quality seal is crucial to the long-term performance of double pane windows.

Benefits of Double Pane Windows

Thermal Performance

Double pane windows have higher thermal resistance compared to single pane windows, contributing to a lower U-value. The U-value is a measure of how well a window prevents heat from escaping. Lower values indicate better insulating properties.

Energy Efficiency

Double pane windows are known for their energy-saving properties. They can reduce energy costs by up to 24% during cold months and up to 18% during hot months, according to the Efficient Windows Collaborative (source).

Noise Reduction

The air or gas-filled gap also serves as a sound insulator, providing a quieter indoor environment.

Reduced Condensation

Double pane windows are less likely to accumulate frost or water droplets, keeping your view clear.

Structural Integrity

The double pane construction enhances the window’s structural integrity, making it more resistant to wind and impact compared to single pane windows.

Safety and Security

Double pane windows are generally more secure than single pane windows as they are harder to break.

In summary, double pane windows are an engineering solution to improve energy efficiency, reduce noise, and enhance the security of residential and commercial buildings. Their technical aspects, from the type of glass used to the nature of the fill gas, are carefully designed to maximize these benefits.

Photo of a cross section of a double pane window

Window Film and Double Pane Windows

While window films offer many benefits, including UV protection and added privacy, not all window films are suitable for double pane windows. Using the wrong type of film can cause the inner pane to overheat and potentially break – this is called a thermal stress fracture – or cause the seals to break.

However, at Concord Window Film, we offer a range of window films specifically designed to be compatible with double pane windows. Our solar control ceramic window film, matte white privacy film, silver reflective film, and safety film are all excellent options for double pane windows less than 40 square feet in size (for one piece of glass).

Find out more about double pane windows and window film.


Double pane windows are an excellent choice for any homeowner looking to improve energy efficiency, reduce noise, and enjoy a more comfortable indoor environment. And when it comes to window films, Concord Window Film offers reliable, top-quality options that are perfectly suited for double pane windows.

🛒 Ready to upgrade your double pane windows? Visit us and shop our range of compatible window films today!

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