Understanding Energy Efficient Window Labels

What Does It Mean?! Understanding Energy Efficient Window Labels

Single pane windows can be detrimental to a home’s energy efficiency. The good news is that a simple window replacement can have huge long-term savings. The bad news – because there are dozens of window brands and models to choose from, you may not understand if you’re going to making the right investment.

Worry not, we’re here to help!

Whether looking online or in-store for a new windows, the window label is the go-to source of information. Once you know what each part of the label means, you’ll be able to make an informed decision about what window to get.

The manufacturer’s label

One panel of the label shows the windows manufacturer and typically includes a model number for the specific design. Below that may be a few product features such as:

  • Frame materials (whether it’s wood, aluminum, vinyl, steel, or fiberglass)
  • Number of panes (single, double, or triple)
  • Type of gas filling in the gap in multi-pane windows (usually argon or krypton)
  • Glazing style
  • Low-E (a glass treatment that reduces UV rays – it helps prevent UV rays from fading your carpet and furniture)

The NFRC Label

You’ll most likely see 4-5 numbers on the label in extra bold type. This is a number calculated by the National Fenestration Rating Council (NFRC). The NFRC is an independent organization that tests windows, door, and skylights to ensure performance and certifies the results of their findings. This label helps to compare characteristics such as:

  • U-Factor (how effectively your windows help maintain heat within your home, the lower the #, the more energy efficient the window is)
  • Solar Heat Gain Coefficient (how effective your window will block heat from outside. Again, the lower the #, the more energy efficient)
  • Visible Transmittance (how much light the window lets in, higher # mean it allows in more light – which could save on costs to light your house)
  • Air Leakage (how much air the window lets in. The lower the #, the tighter the seal)
  • Condensation Rating (not every NFRC label will have this, but it shows how well your window resists condensation. The higher the #, the higher the resistance – something to consider if you live in area where your home may be susceptible to mold/mildew damage.)

The Energy Star Label

If the window meets certain requirements for your geographical location, it’s label may also feature the Environmental Protection Agency’s (EPA’s) Energy Star Logo. This label simply shows which windows have the most energy efficient properties based on your location.

Have any questions about what windows would be best to make your home more energy efficient? Contact A-Abel for help today!

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