Single vs. Double Pane Windows

In times past, windows were a luxury that only the very rich were able to afford. Nowadays, there is a virtually endless supply of choices when it comes to windows. How they look, long term maintenance and how well they keep the elements at bay are important considerations. An existing custom single pane may be drafty. A similar energy efficient, well sealed dual pane may be expensive. While it is not always feasible to replace all of the windows in a home, it is important to consider available options.

Curbside Impact


An older home is likely to have uninsulated single pane windows. When compared to newer insulated and coated dual panes, these single panes are far less efficient. There are several factors to consider when making a decision whether to upgrade to dual pane or improve existing single pane windows. Windows can have a huge visual and environmental impact on a home. From a curbside perspective, windows can make or break the exterior appearance of your home. Many older homes have specialty windows that offset and highlight the architecture of the house. A strategically placed window allows you to enjoy the view or light and warm your home naturally. However, even a well placed or beautiful window that is not well insulated can mean a lot of wasted money.

Dual Pane

Modern technology has been applied in several ways to make dual pane windows energy efficient. Not only do they have two layers of glass, but most also have insulating gas between the layers. Many newer dual pane windows are coated with reflective material called Low E to keep hot summer rays from penetrating and keep winter warmth inside. Additional tinting can be done to further reduce heat transfer from windows facing strong sunlight. Even the vinyl framework of most dual panes is intended for energy efficiency--it diffuses heat better than the aluminum and wood used on older windows.

Cost Analysis

Dual pane windows can save anywhere from 20 percent to 30 percent of your annual energy costs. But, before you invest in a costly upgrade to dual pane windows, analyze all factors to determine the return on such an investment. Not only do you have the cost of windows, trim and installation, but you will also likely need to repair the siding and trim as well. If you move windows and you have older siding, you may need to replace the entire exterior face.

Single Pane

There are many things you can do with single pane windows to increase energy efficiency if you cannot justify the cost of replacing them with dual panes. If drafts come in from outside, you can reduce the effects by caulking around the interior and exterior of the single pane. Coatings can be applied to reduce the impact of sunlight without eliminating the natural warmth and available light. In areas where weather is extreme--either cold or hot--you can use quilted curtains to add additional insulation.

Benefits of Upgrades

When windows are not installed properly, the space between dual panes may become cloudy as condensation occurs. A dual pane window is easier to replace than repair when it is damaged or broken, so it does have potential for a greater environmental footprint than single panes. Whether you upgrade to brand new dual pane windows or improve existing single panes, you will experience savings through improved efficiency.