Windows are a major source of heat loss in the winter and heat gain in the summer. Up to 30% of a home’s heating and cooling energy can be lost through windows. Single-paned windows are the least energy-efficient because they offer little resistance to heat flow. Double-paned windows, especially those with an inert gas like argon or krypton in the space between the panes, can significantly reduce this energy loss.

When it’s cold outside, the inner pane of a double-paned window stays warmer than a single pane, reducing the cold draft you might feel near the window. In the summer, the outer pane absorbs much of the sun’s heat before it can reach the inner pane, helping to keep your home cooler. This reduction in heat transfer means your HVAC system doesn’t have to work as hard, which directly translates to lower energy consumption and lower utility bills.

What to Look For in Energy-Efficient Windows

To maximize the impact on your energy bill, look for windows with the following features:

• Low-E (Low-Emissivity) Coating: This microscopically thin, transparent coating reflects infrared heat while letting visible light pass through. In the winter, it reflects heat back into the house, and in the summer, it reflects the sun’s heat away.

• Insulating Gas Fill: The space between the two panes of glass can be filled with an inert gas like argon or krypton. These gases are denser than air and provide better insulation, further slowing down heat transfer.

• Spacer: The material that separates the two panes of glass is also important. Warm-edge spacers are made of a less conductive material than traditional aluminum, which reduces heat loss at the edge of the glass.

Upgrading your windows is a smart investment that not only makes your home more comfortable but also provides a noticeable and long-term reduction in your heating and cooling costs. Combined with a comprehensive home energy assessment, new windows can be a key part of making your home more energy-efficient and saving you money.