Windows offer natural sunlight and a glimpse outdoors while keeping your home comfortably sealed against the elements and limiting the amount of ultra violet rays transmitted through the glass. When shopping for quality window replacements, look for the National Fenestration Registration Council (NFRC) label, which is a requirement for all New Mexico window replacements.

We are Glass-Rite of New Mexico, a manufacturer and installer of custom windows in Albuquerque and Southern Colorado for 30 years.  Here is our overview of the NFRC label and what it tells you about a window’s energy performance.

  1. U-Factor: measures how well a window prevents heat from escaping. U-factor ratings usually fall between 0.20 and 1.20. The lower the U-Factor, the warmer your home.
  2. Solar Heat Gain Coefficient (SHGC):  indicates how well a window blocks heat from the sun. SHGC is expressed as a number between 1 and 0. A lower number indicates the window transmits less heat from the sun keeping your home cooler.
  3. Visible Transmittance (VT): measures how much visible light passes through a window. VT is expressed as a number between 1 and 0. A higher VT means more light is transmitted.
  4. Air Leakage (AL): measures how well the window keeps air out. AL is usually rated between 0.1 and 0.3. The lower the rating, the better the air leakage prevention. Since this is a voluntary rating, not everyone choose to display it, but we at Glass-Rite do as we are very proud of our window ratings.


NFRC labels use the whole window including the frame when testing to determine energy code ratings. NFRC energy ratings for Glass-Rite’s Energy Quest vinyl windows are consistently competitive due to the design of our windows. The advanced interlocking system and a tight seal make them an excellent fit for New Mexico’s extreme temperatures and windy conditions. Multiple rows of weather-stripping offer further protection limiting air and dust infiltration in the frame, and a dual weep sill drainage system carries water away from the window.

The efficiency of our Energy Quest vinyl windows even comes with a view as the frames have a narrow site-line which maximizes the glass but still provides optimum insulation. Glass-Rite encourage you to look for the NFRC label when shopping for new or replacement windows and invites you to visit our website for more information on our Energy Quest vinyl windows.