Today, most homeowners try all possible ways to save more money on projects related to home improvement. Replacing glass windows is a very popular project that homeowners invest in with the aim of enhancing energy efficiency in their homes. Everyone wants windows with the highest energy ratings to reduce energy costs.

But how will you know the windows you’ve or the ones you are getting for replacement have great energy ratings? There is a lot to know regarding energy efficiency in windows. It’s important you learn more to ensure you don’t invest in poorly rated windows.

how energy efficient windows will save money

Here are the details about energy ratings for windows. Read on to know how you will stand a better chance of getting the best-rated replacement windows.


Labels to Check on the Windows

The first thing you need to do before considering any window to be energy efficient is ensuring that it has proper rating labels. Any seller or manufacturer can claim their windows have the best energy efficiency but that doesn’t matter as long as they are not properly labelled.

The most crucial label you should check first is an Energy Star label. The seal specifies the specific climatic regions that the window is certified for.

Energy Star raring is very important in homes within regions that experience extreme weather conditions. If your windows are not certified for your climatic zone, then they might get damaged or broken quite easily.

Another important label to check is from the national rating council. This is an organization recognized in the door and window industry. It reports on energy efficiency statistics for various products, including windows, to assist consumers to decide the options that are more energy efficient.

It is important to ensure that the replacement window has both labels. This will let you know you are investing in a good product. If you choose Majestic Glass products, you will be assured that you are investing in windows that meet energy efficiency requirements.

glass replacements with energy efficieny labels

What are Energy Ratings for Windows?

There are several factors that determine the energy rating of a window. All factors are important. The main factors affecting energy rating include air leakage, visible transmittance, heat gain, and U-factor.

Here are more details about these four factors and why they are all important to consider when looking for replacement windows for your home.


A window’s U-factor rating is a window’s ability to prevent heat from leaving a room. U-factor is measured within the range of 0.20 to 1.20. A lower rating means that the window has a better U-factor, thus it will keep more heat within your home.

Investing in windows with lower U-factor rating is especially important for people residing in regions with extreme weather conditions. For instance, some regions get extremely cold winters, thus you would want to have windows that retain heat indoors. This will save you money on heating costs.

Heat Gain Rating

This is a measure that determines how well a window can prevent heat from getting into a room. It’s measured from a range of 0 to 1. A window with a lower heat gain rating means that it’s better at keeping the heat outside.

It would help a great deal when you have windows with low heat gain rating since it will assist you om saving money during summer. Investing in windows that are reliable at keeping solar heat outside means that you won’t overwork your air conditioner during summer as you try to keep the indoors more comfortable for your stay.

Visible Transmittance

The visible transmittance of a window is measured based on the amount of natural light that it lets into a room. It’s important to consider this rating since it lowers energy bills since you will not rely a lot on artificial lighting.

Visible transmittance is rated from 0 to 1. A window with a higher rating will allow more natural lighting into a room. Technology on windows and glass has advanced greatly such that even if the window lets in more natural light, it won’t make the room hotter.

Glass windows have evolved greatly such that there are modern types that allow more sunlight in while blocking out solar rays that lead to heat gain. By having more natural lighting in your home during the daytime, you will not have to keep your bulbs on.

Air Leakage

Most homeowners face the challenge of their windows becoming drafty. A drafty window can make you lose a lot of money since it allows outside air to enter the home, resulting in stress on the air conditioner and furnace.

When looking for a replacement window, check the one with the lowest number on air leakage. For windows to be rated as Energy Star, their leakage rating should be less than 0.3. The rating indicated the amount of air that can enter your home through the window.

To comply with air leakage ratings, windows should be installed professionally to make sure that they’re no leaks or cracks between the sashes and frames.


Get Windows With the Best Energy Ratings at Majestic Glass

If you are searching for replacement windows in Sydney, your search should end at Majestic Glass. All products from Majestic Glass are energy efficient. They are all designed for maximum energy efficiency regardless of the season.

Our excellent services and outstanding energy ratings on windows make the replacement process smooth and easy from start to completion. We have served thousands of happy customers, and that’s why we are named as Sydney’s number one door and window installers.

If you are looking for a way to make your home look great and more energy efficient, Majestic Glass has got you covered. We have different styles, colors, and types of windows to choose from. Also, we customize windows to ensure they fit perfectly in the existing window openings for a proper and secure fit. Contact us today for more information and a free estimate.

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