Energy Star Requirements for Windows

If you’re shopping for eco-friendly home products, Energy Star is an essential name to know. A voluntary partnership program that encourages manufacturers to develop energy-efficient products and helps consumers make informed decisions, Energy Star and its partners have helped American families and businesses save more than $500 billion in energy costs since 1992. It has also prevented 4 billion metric tons of greenhouse emissions from entering the earth’s atmosphere. Clearly, Energy Star knows a thing or two about efficiency. But as you peruse options for replacement windows, you might wonder what makes the Energy Starso special. What are the Energy Star requirements for windows?

Why Choose Energy Star?

Established by the U.S. Environmental Protection Agency (EPA), Energy Star sets strict efficiency standards to help homeowners and businesses reduce their energy consumption and lower utility costs. Energy Star-rated windows provide superior insulation, minimize heat transfer, and improve indoor comfort. Whether you’re most concerned about decreasing your family’s carbon footprint, lowering your energy bills, making your home less drafty, or qualifying for rebates or tax incentives, you won’t regret purchasing Energy Star windows.

Exploring the Energy Star Requirements for Windows

For windows to earn the Energy Star Label, they must be independently tested and certified to meet or exceed numerous criteria, which vary depending on the climate zone (Northern, North-Central, South-Central, and Southern). For example, in colder northern regions, windows must have a lower U-factor for better insulation. In southern regions, a lower SHGC is crucial for reducing cooling loads. Generally, the following are the main performance metrics for Energy Star certification:

• U-factor: The U-factor measures how well a window insulates. The lower the U-factor, the better the window keeps heat inside during winter.
• Solar Heat Gain Coefficient (SHGC): The SHGC quantifies how well the window blocks heat from the sun. The lower the SHGC, the less solar heat enters the home.
• Visible Transmittance (VT): The VT indicates how much natural light is let inside by the window. Although this isn’t necessarily considered a core requirement, it helps convey the efficiency and comfort delivered by the window.

To view the certification criteria for residential windows, which are broken down by climate zone, visit the Energy Star website.

To create these energy-efficient windows, manufacturers must take a number of different factors into consideration. High-quality, durable frame materials can reduce heat transfer and boost insulation. Two or more panes of glass with an air- or gas-filled space between them can provide a significant insulation boost — not to mention increased impact resistance and sound insulation. Low-e glass reflects infrared light, which helps keep heat inside in winter and outside in summer. Finally, warm edge spacers keep the glass panes properly spaced and may also insulate the pane edges to reduce heat transfer. Clearly, many different elements must come together to produce a great window!

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If you’re shopping for new windows, perusing the Energy Star requirements for windows is certainly a good place to start. The criteria can help you understand the performance elements behind energy-efficient windows and how your climate zone factors into the equation, which may help guide your quest.

Are your windows in dire need of replacement? Liberty Home Solutions can help. We offer energy-efficient replacement windows from SoftLite, which are designed in a state-of-the-art facility and precisely engineered to the strictest of standards. Their automated manufacturing process and top-quality materials ensure that you end up with efficient, long-lasting, and durable windows. Plus, as you might have guessed, SoftLite is an Energy Star partner, and many of its windows are listed on its “Most Efficient Products” list. When you’re ready to get started, request a free quote for replacement windows. We would be happy to help you find the perfect windows for your property.