Single Pane vs Double Pane Windows: What’s the Difference?

Double Pane Windows Standing in Plant

This article was originally published on July 26th, 2018. We have completely updated the article with up to date information and more insights.

Since we originally wrote this article, many customers continue to ask an important question, do I really need double pane glass windows?

The type of windows you have installed in your home can either make you save or spend money, either now or down the road.

And we’re not just talking about style or material. The number of glass layers in your window (single pane or double pane) can have a big impact on the comfort of your home.

But what’s so different about the two?

In this post, we will explore the main differences between Single Pane and Double Pane windows so when you are ready to buy windows, you pick the right type for your home.

Time Saver: If you are buying an exterior windows replacement, for all us who live in the North, like Chicago, and not in 72-degree tropical country, I’ll save you some time. Go with a double pane window, you will be glad you did.

What Are Single Pane Windows?

Single pane windows have only one layer of glass, which means they have no insulation.

Windows with only one layer of glass aren’t able to block outside noises or temperatures from entering the house. Chicago is one of the noisiest cities in the United States according to NPR. If you live near a busy street, the sounds of driving cars will be louder than they would with double pane windows.

The outside temperature also affects the inside of your home more with single-pane windows. Your house will get colder during the winter and warmer during the summer.

To keep the house comfortable, you’re air conditioner or heater will have to work harder. In other words, you spend more money on your energy bill.

What Are Single Pane Windows?

What are Double Pane Windows

Instead of one layer of glass, double pane windows have two. These two layers are separated from each other by another thin layer of empty space. The air trapped inside this space serves as the window’s insulation.

This is how it works.

The air between the two sheets of glass traps the outside temperature inside with it. For example, in  Chicago, we have very cold winters, sometimes as low as -50  with the windchill. As the winter cold makes its way through the first layer of glass, it gets trapped in the middle space. This means it never makes its way through the second layer of glass and inside the house.

Because the outside temperature doesn’t affect the inside of your home, you don’t have to spend extra money keeping your house comfortable. In fact, your savings with a double pane window can be as much as 24% during the winter and 18% during the summer.

The double panes also block noise from entering your home as well.

Double pane windows do cost more than single-pane windows, but they keep the temperature in your home consistent. So you can lower your heater and turn off your air conditioner.

Double Pane Windows

Which Type of Window Is Better?

In most cases, you’ll want double pane windows for your home, but there are a few situations where you might benefit from single-pane windows.

For example, because there is only one layer of glass, single pane of glass is less expensive than double pane windows. This can be helpful for people who don’t have a lot of money to spend on their windows.

Just remember, single-pane windows may cost less to install, but over time, they’ll make your energy bill rise.

But this might not be an issue if the temperature where you live stays mild and consistent all throughout the year. If you don’t have to worry about your house getting too cold or too hot, single-pane windows could be a cost-effective option.


The type of window you choose directly relates to how much money you’ll spend on heating and cooling your house. When it comes to single pane vs double pane windows, having two layers of glass usually saves you money and keeps your house more comfortable.

Here is a quick overview of the pros and cons of double pane windows.

Pros of Double Pane Windows:

  • Double-paned windows keep both cool and warm temperatures inside your home and in turn reducing energy costs.
  • Adding Other Technologies can help you save even more, up to 50% on your energy bill.
  • Double-paned Windows requires you to use less energy to cool and heat your home which in turn uses fewer fossil fuels, lowering emissions of greenhouse gases.
  • Double-paned windows can help keep your house insulated from outside noise.

Thinking about replacing your single pane windows to an energy-efficient window? Take a look at these five benefits of double pane windows.