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Energy Efficient Windows: The Difference Between U-Factor, Glazing & Low-E

When looking for replacement windows, all of the terminology can get confusing. This is especially true when talking about Energy Efficient Windows. What is the Difference Between U-Factor, Glazing & Low-E?

  1. What is U-Factor? Every window is labeled with a U-Factor, which is an indication of the insulation value of that window. The U-Factor measures the rate of heat transfer. The lower the U-factor, the better the window insulates.
  2. What is Glazing? Today, single pane windows are a thing of the past. Now, double- and triple-glazed windows are ruling the industry. The typical glazed window consists of two or more panes of glass separated by a spacer and filled with argon or krypton gas. This helps insulate the window and makes it much more energy efficient.
  3. What is the Solar Heat Gain Coefficient? SHGC measures the fraction of solar energy transmitted, an indication of how well the window blocks heat from the sun. SHGC is measured on a scale of 0 to 1. The lower the SHGC the better.
  4. What is Visible Transmittance? VT is the amount of light a window allows through. VT is measured on a scale of 0 to 1, with a higher number indicating a window that allows more light through.
  5. What is Air Leakage? Air leakage measures the amount of air that is allowed to pass through the joints in a window. The lower the AL, the less air leakage.
  6. What is Condensation Resistance? Condensation resistance measures how well a window stands up to moisture buildup. It is measured on a scale of 0 to 100, with a higher number indicating less buildup.
  7. What is Low-E? Low emissivity, better known as Low-E, is an invisible metallic coating designed to reflect infrared light and keep heat inside where it is supposed to be: inside in the winter and outside in the summer. Low-E glass also reflects ultraviolet light, which helps protect your furniture from prematurely fading.

Energy Efficient Windows from Architectural Window Supply in Baltimore

Architectural Window Supply has been Baltimore’s premier window supplier since 1995. We offer a wide variety of cost-effective, yet high quality windows sure to add style to any home. ur staff is factory-trained and experienced in the window industry, which means they’ll offer informed advice on your window, from function to performance.

If you have any further questions about our blog, “Energy Efficient Windows: The Difference Between U-Factor, Glazing & LowE,”or if you wish to schedule a free consultation, please contact Architectural Window Supply by calling 410-266-5254 or visit our website! You can also follow us on Facebook and Twitter as well!


This entry was posted on Tuesday, May 21st, 2013 at 7:57 pm. Both comments and pings are currently closed.