What the Labels are Trying to Tell You: An Explanation of the NFRC Label

Image 2

Buying new windows can get more complicated than one would imagine, especially for a first-timer. You might have heard of the term Energy Star and think that it’s all you need to check to know which product is best for your home. There is more information that is helpful in choosing your window.

While looking at window products online and in the store, it’s possible that you have already come across the NFRC label — and ignored it altogether. If you want to purchase the window most appropriate for your home’s climate and orientation, and fine-tune the window placement in your home, you must start taking this label more seriously.

The NFRC and Its Role

The National Fenestration Rating Council (NFRC) is a nonprofit organization committed to providing consumers and stakeholders including homeowners, builders, architects and engineers with the necessary information and updates in the window industry. Established in 1989, they cater especially to those who are in the market for energy efficient products.

The NFRC label that can be found on fenestration products including windows, doors, and skylights indicates values that determine their energy efficiency. However, the values will be of little help IF you don’t know how to interpret them, and if you are unsure of what your home needs.

The Label, Values, and Their Meanings

Below is an example of an NFRC label, with the parts and values described and defined.

  1. NFRC InsigniaThis gives stakeholders the assurance that the product has been independently evaluated and rated and will perform “as specified.”
  2. Solar Heat Gain Coefficient (SHGC)The rate of solar heat transfer through a window from either direct transmission or absorption. The lower the SHGC, the lower the heat gain.
  3. U-factor – The rate of heat transmission and transfer depending on temperature, size, and components of the window. The lower the U-factor, the more energy efficient the unit is.
  4. Residential and Commercial Application Values – Energy efficiency ratings can vary depending on the size of the window as well as the type of building where it will be installed. Thus, the NFRC provides ratings for both residential and commercial applications.
  5. Manufacturer’s Name – The name of the window manufacturing company.
  6. Product Description – Indicates the product’s model number and other specifications such as the type of glass and air or gas fill.
  7. Visible Light Transmittance (VT) – The amount of visible light transmitted through a window unit. The value will depend on the size, glass-to-frame ratio, and transmittance of the glass.
  8. Air Leakage (AL)The rate of infiltration; the lower the value, the smaller the amount of air and energy that leaks through the unit.


Now that you have learned more about the terms and values of the NFRC label, you are left with no excuse to purchase window products that are less than appropriate for your home! However, to make better use of the knowledge I’ve just shared with you, I suggest you take the time also to learn about the specifications recommended for your particular climate.

About the Author

Driven by the goal to build a home improvement company committed to quality and integrity, Jeff Jones established Jones & Associates in 1987. With the support of his wife L’Anna, Jeff’s efforts paid off in 2007 as his company started being regularly chosen by Qualified Remodelers as one of the Top 500 Contractors in the United States. When not catering to client needs, Jones enjoys outdoor activities with his family, as well as serving community and religious boards.




  • Loading
  • You May Also Like