7 Best Energy-Efficient Windows (to Save Energy and Money)

You could be paying 25-30% more for electricity than you should because of heat loss and heat gain through inefficient windows. You can save up to one-third of your energy bills by upgrading or replacing your old windows with the best energy-efficient windows.

7 of the best energy-efficient windows are as follows:

  1. Energy Saver R-5 Window Glass
  2. Laminated Window Glass
  3. Solarban 70XL Window Glass
  4. Ultimate Triple Pane Glass 
  5. Ultra Pane Glass 
  6. Double Pane Extreme Low-E Window Glass
  7. Super Spacer Window Glass

Each energy-efficient window listed above is designed to prevent cool air or hot air inside your house from escaping outside. They have improved insulation that helps reduce your energy usage. This is the reason why they are also called energy-saving windows.

Read on to learn more about the best energy-saving windows available today, why they are the best, and some tips on choosing the best ones. 

Best Energy Efficient Windows

best energy efficient windows

Energy-efficient windows are designed to prevent indoor cooled air or heated air from escaping outside. As such, they could reduce your energy bills. That is why they are regarded as energy-saving windows.

These windows offer additional insulation to prevent indoor to outdoor heat exchange. According to the U.S. Department of Energy, these modern insulated windows offer considerable energy savings.

Depending on your house’s location, you have the potential of saving from $126 to $465 per year if you replace your old single-pane windows with energy-efficient windows.

Some of the most energy-efficient windows are those with dual-pane glasses. The insulation ability that these window glasses offer is nearly twice as much as single pane glasses. After maximum energy efficiency, your best option is to use windows with triple glass panes.

Here are some of the best energy-efiicient replacement windows that you can consider. They will surely help you reduce your energy bills:

1. Energy Saver R-5 Window Glass

This glass can provide 25% more insulation than other window glass panes. It will provide a comfortable temperature in your home, whether it is summer or winter. Its double-paned construction of high-performance Low-E (low emissivity) glass makes it very energy efficient.

This insulated glass unit is also filled with Argon gas. Its insulated frame and sash are made of VyCore Foam. It also comes with the Warm Edge Spacer System, which is resistant to scratch, very durable, and easily cleaned using common glass cleaners.

2. Laminated Window Glass

This window glass consists of three glass panes. It has two panes of glass that sandwich a rigid polyvinyl butyral interlayer. This system offers an outstanding ability to protect against harmful UV rays. It even prevents intruders from entering and keeps outside noise from coming in.

It has insulating glass with a Low-E coating made of two layers of thermal protection, ensuring comfortable temperature all year round. The space (between the two glass panels) is 99.97% filled with Argon gas. This further reduces heat transfer, ensuring the energy efficiency of the home.

In terms of noise reduction, this glass is number one. It is the best glass that can deaden outdoor sounds. This glass system is already being used in houses near airports and railroads. Jet canopies also use this system.

It is the same system used in making car windshields. This glass system can withstand a maximum of 30 baseball bat swings before the bat can even make a single hole in the glass.

3. Solarban 70XL Window Glass

This window glass can block 99.97% of harmful UV light. It is an upgraded glass coating that you can add to a standard package of glass systems. This glass does not change the U value of the parcel but only its UV protection.

Its ability to block UV light help prevent color fading and damage to window treatments, furniture, and flooring, while still allowing natural light to come in.

The space (between the two glass panels) has 99.97% Argon gas. This further reduces heat transfer and will make the home comfortable in all seasons.

An optional feature of this glass is the Spacer System. The Warm Edge Technology Spacer is a cutting-edge tin-plated spacer system that separates the glass panes. It has a patented one-piece U-Channel that forms a strong thermal barrier to reduce heat loss.

4. Ultimate Triple Pane Glass

This glass holds the number one position among the top brands of energy-saving windows. It has insulating glass with 2 Low-E silver oxide coatings on 2 glass panes made from two thermal protection layers.

There is an additional third pane of Low-E glass to ensure maximum comfort throughout the year.

The glass panes have a U-value of 0.16 to 0.9. Their solar heat gain coefficient is from 0.21 to 0.24, with an overall IGU thickness of 1 inch, a condensation resistance factor of 72, and visible transmittance of 0.40.

This glass window is also number one in noise reduction. The space between the insulated glass is also 98.8% filled with Krypton gas. This reduces heat transfer, ensuring that the home is energy efficient all year round.

This glass also comes with a standard spacer system made of 100% polymer structural foam. This spacer system’s NO-metal formula blocks the escape path of heat and offers the best in thermal performance.

5. Ultra Triple Pane Glass

This particular window glass features 2 Low-E silver oxide coatings on two glass panes made from two thermal protection layers. It also has a third glass pane made of Low-E glass to achieve maximum comfort for all seasons.

best energy efficient replacement windows

The glass panes have a U-value of 0.24 to 0.25. Their solar heat gain coefficient is from 0.21 to 0.27, overall IGU thickness of 7/8 inch, a condensation resistance factor of 62, and visible transmittance of 0.40.

This window glass can block 90% of the sun’s UV rays. It will prevent color fading and damage in window treatments, flooring, and furniture. The space between the two glass panes also has 99% Argon gas.

This further reduces heat transfer increasing the energy efficiency of a home. The Warm Edge Technology Spacer system is also an option for this type of window glass.

6. Double Pane Extreme Low-E Window Glass

This low-energy window glass combines value and high energy efficiency, and outstanding UV protection. It has double pane insulated glass with 2 Low-E silver oxide coatings (14 layers) for increased comfort in all seasons.

The glass has a U-Value of 0.27 to 0.30. Moreover, it has a solar heat gain coefficient of 0.29, an overall IGU thickness of 3/4 inch, a condensation resistance factor of 58, and a visible transmittance of 0.61.

The glass can block up to 80% of the UV rays of the sun. This will allow natural light to prevent indoor flooring, furniture color, and window treatments from fading.

An optional feature of this glass is the Warm Edge Technology Spacer system. It is a highly advanced system that uses tin-plated steel spacers to separate the glass panes. There is also a strong thermal barrier provided by the patented one-piece U-channel that minimizes heat loss.

Inserted in the space between the two glass panes is Argon gas. About 98.8% of this space is filled with this gas. This feature reduces heat transfer further, thus making your home truly energy efficient.

7. Super Spacer Window Glass

This material is made from 100% polymer structural foam. It comes with NO-metal formula, which can block the heat’s escape path, allowing it to provide the best thermal performance. Super Spacer usually lowers the U-value of the glass by 0.01.

This spacer was able to withstand 140°F, constant UV bombardment, and from 95 to 100% humidity in the P-1 test. According to test engineers, IT is the most rigid durability and accelerated aging test for glass windows globally.

Two Options to Reduce Window Energy Loss

If you want to use energy-saving windows to improve your home’s energy efficiency, you have two options: either update your current windows or replace them altogether:

Update Existing Windows

It’s a waste to throw away your windows if they are still in good condition. The most cost-efficient method is to upgrade them. By doing this, you’ll be able to enhance the comfort inside your home without spending so much money.

Here are the things you have to do if you choose this option:

  1. Inspect all your windows for air leaks;
  2. If leaks are found, caulk and weather-strip all of them. You can fix it yourself if you know how or ask a professional if you don’t;
  3. If necessary, add window treatments and coverings, e.g., blinds, quilts, insulated cellular shades, blinds, awnings, shutters, and shades;
  4. Add window panels or storm windows; and
  5. Add exterior shading like exterior blinds, awnings, overhangs, etc.

Replace Windows

You will surely make your home more energy-efficient if you replace your existing windows with the best energy-efficient replacement windows. There are also two options on how you can do this:

  1. Use the existing window frames and replace the old window glass panes; and
  2. Replace the whole thing, including the frame and the glass panes.

You have to consult with a window installer and the replacement windows supplier on your best course of action. When counseling with the window supplier and the installer, bring up the following points:

  • Type of window frame that is best for your house
  • The kind of glazing that is best
  • If the windows will need spacers and gas fills
  • Which window system they recommend based on your location 

Things to Look for in Energy Efficient Windows 

If you want to replace your existing windows with energy-efficient ones, you need to know the important elements that the window must possess.

Here are the three key elements that you need to see in a good energy-efficient window:

1. Thickness and Glazing of the Glass

The glass is the most important thing about a window. In energy-efficient glass windows, there are two important things that you need to consider: their thickness and their glazing.

energy efficient windows

Thicker panels will enhance the retention of heat. Glazing can save from 40 to 70% of the heat without reducing the light’s capacity to pass through the pane.

2. Insulation

The glass pane’s insulation will also prevent indoor heat from escaping during winter and outdoor heat from entering during summer. Insulation can be achieved through cellular shades, the application of insulation film, and weather sealing.

3. Window Frame

The materials and the construction that went into the making of the frame are also necessary because they also affect the window’s energy efficiency. To reduce heat, use wood, fiberglass, or vinyl window frames. Metal frames conduct heat, which can result in considerable heat loss.

Things That Can Affect the Effectiveness of Energy Efficient Windows

Aside from the build characteristics of the energy-efficient window, other things can affect its actual performance.

1. Installation

If an energy-efficient window is not installed properly, it will not reduce your energy costs. The window should be installed by a professional so that it will prevent air and water infiltration.

2. Proper Selection and Placement of Window Glasses

You need to choose the right windows for the correct location. Different locations in your house need certain Low-E glass coatings. These coatings are layers of thermal protection materials inside the glass.

The functions of these coatings are:

  • Block harmful UV rays to prevent fading of flooring, furniture, etc.
  • Retain interior heat and reflect winter cold.
  • Retain interior cooling and reflect the summer heat.

3. Region

You should also consider the geographic area where you live and its prevailing climate when selecting energy-efficient windows. Look for windows that are specifically designed for the overall climate in your area. 

Conclusion: Best Energy-Efficient Replacement Windows

If you are updating or replacing your old windows, it would be best to use modern windows that are energy efficient.

The best among these energy-efficient windows include the following:

  1. Energy Saver Window Glass
  2. Laminated Window Glass
  3. Solarban 70XL Window Glass
  4. Ultimate Triple Pane Glass
  5. Ultra Pane Glass 
  6. Double Pane Extreme Low-E Window Glass
  7. Super Spacer Window Glass

Here are your options to reduce window energy loss:

  1. Update Existing Windows
  2. Replace Windows

Again, here are the things you should look for in energy-efficient windows:

  1. Thickness and Glazing of the Glass
  2. Insulation
  3. Window Frame

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