In This Post, You Will Learn:

  1. Impact of windows on energy costs and HVAC

  2. Energy efficient windows

  3. How money can be saved by upgrading

  4. Other window benefits

  5. What to look for in energy efficient windows

Impact Of Windows On Energy Costs and HVAC

Windows, especially older, single pane windows, make your energy bill sky rocket. They can be responsible for 10-25% of your electric bill by allowing heat to escape in the winter and warmth from the sun to enter in the summer.

The problem with older windows is that the single pane window allow air to pass into the home. With these older windows, there is little to no insulation from the outside temperature. The same can be said for the wooden frame. Over time, the wood begins to rot and crack. This allows air to flow through. Ultimately, you are wasting energy during the hot summer because your air conditioner is trying to keep up with all of the cold air that is going out your windows and the hot air that is coming in. A similar statement can be made for the cold winter, except this time, it’s the hot air coming from your heater that is escaping from your home. 

Replacing those old, worn out windows can make all the difference.

Energy Efficient Windows

Today, advanced window technology comes at affordable and reasonable prices. Homeowners are opting to replace their older, single pane windows with new, dual pane windows. Dual pane windows are made up of 2 panes. In between the panes of glass, there is a vacuum or gas that work to reduce heat transfer. These windows are insulated and help to seal air leaks as well as keep your power bill down.

Typically, energy efficient windows have the following features:

– Laminated insulating glass
– Heat reducing glass tints
– Low-E coatings
– Improved framing materials
– 2 or more panes of glass
– Warm-edge spacers between the window panes

How Much Money Can You Save By Upgrading?

The amount you could save by installing new energy efficient windows depends on what kind of windows you currently have. If your old windows are single-pane glass with wood frames, then yes; you can save a lot of money. Also, let’s say your home has old aluminum, single-pane windows, as do many in the San Joaquin Valley area. Your current windows do not insulate your home well, so if you upgrade to gas-filled, double-pane windows with non-conductive frames, you will see lower power bill costs. However, if you upgrade when you already have double-pane vinyl windows, you will still see savings, but not as drastic. New, energy-efficient windows will be way better at keeping your home cool in summer and warm in winter.

The Energy Star program says that Energy Star certified window products can lower your energy bills up to 15 percent. After 1 year of having replaced single pane windows, homeowners saw an average of $101 to $583 in savings from reduced energy costs. After a year of replacing double-pane, clear glass windows, homeowners saved an average of $27 to $197 dollars in energy costs. For those who are more environmentally concerned, an average of 1,006–6,205 pounds of CO2 are reduced after 1 year of replacing single-pane windows. 246–2,001 pounds of CO2 are reduced after 1 year of replacing double-pane, clear glass windows

As mentioned earlier, if you already have double-pane windows, new ones won’t make as much of a difference. In this case, you can benefit from other home upgrades. Click on “LEARN MORE” to get more info on Home Upgrades that can better help you!

Other Window Benefits

Cutting your energy bills isn’t the only benefit of replacing old windows. It can also raise your home value. Also, new windows with vinyl frames don’t require as much maintenance as older windows with wooden frames. Then there’s the V in HVAC—ventilation. If your old windows are hard to open, replacing them with easy-to-open windows could bring in more fresh air.

What To Look For In Energy Efficient Windows

  1. Low-E Coating:

    Low-E is an energy-efficient coating that minimizes the amount of ultraviolet and infrared light that comes through the glass and into your home. Low-E coating helps either retain or reflect heat into your home while reducing energy costs throughout the year.

  2. Insulated Glass:

    Argon and Krypton gases enhance the energy efficiency to your windows. Both gases perform as an insulator and work with the Low-E coating to create a more comfortable home environment. Basically, they make it harder for any heating and cooling to pass through the glass.

  3. U-Factor (U-Value):

    When buying a new window, it’s important to consider the U-Factor. A U-Factor is the measure of heat transfer from the whole window including the frame, sash, and glass unit. A lower U-Factor means the window has a higher quality insulation and a greater resistance to heat flow.

  4. Energy Star Label:

    ENERGY STAR is the trusted, government-backed symbol for energy efficiency helping us save money and protect the environment through energy-efficient products and practices. The ENERGY STAR label was created to, “Reduce greenhouse gas emissions and other pollutants caused by the inefficient use of energy.”

U-Factor label

U-Factor label

Energy Star Label

Energy Star Label


Energy Efficient windows can impact your energy costs significantly, especially if you have older, single pane windows in your home. The older windows in your home do not help to maintain the heating or cooling inside, instead it allows for air to pass through the windows. This creates higher energy bills due to HVAC systems working harder to make your home comfortable during winter or summer months. Energy Star products are approved by the government as energy efficient. When looking for energy efficient windows, it’s important to keep an eye out for the Energy Star label as well as checking if the product has a low U-Factor, Low-E Coating, and insulated glass.