Importance of Window U-Factor Rating


The “u-factor” of a window is a rating that was developed by the NFRC (the National Fenestration Rating Council). This rating is a measurement of how much heat loss or cool air loss occurs through a window. The better the insulating qualities of a window are, the lower its u-factor rating is. Most windows have a u-factor of somewhere between 0.25 and 1.25.

There are several reasons why it’s important to choose a window with the lowest u-factor possible:

  •  The lower the u-factor of the window is, the less heat or cool air you’ll lose through the window, which means the lower your energy bill will be. Put simply, if you choose windows with a low u-factor, you’ll likely save money in heating and cooling bills.
  •  Windows with lower u-factors will increase your property value. Whether you plan on selling your home soon or holding onto it for years to come, purchasing energy-efficient windows is a good investment with regard to maintaining or increasing your property value.
  •  You may qualify for a tax credit if you purchase new windows with an Energy Star rating from the federal government, which indicates that the windows have a low u-factor.
  • For more information about windows with a low u-factor, talk to an experienced window professional. He or she can provide more details about these energy-efficient products and will also be able to make recommendations regarding which windows are best for your home or office and which will fit into your budget.



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