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What Do Those Window Labels Actually Tell Eau Claire, Wisconsin Homeowners? Pella Wants You To Know.

What Do Those Window Labels Actually Tell Eau Claire, Wisconsin Homeowners? Pella Wants You To Know.

The buying cycle for replacement windows and doors can be quite a process for the average homeowner. Not only are there many styles, materials and brands to evaluate, but the industry codes and ratings can be baffling, leaving people frustrated. Acquainting yourself with window speak will not only educate you, but will probably foster a more enjoyable experience when selecting your new windows. Whether you are replacing rotting, old windows and doors, undertaking a remodel or building a new home in Eau Claire, the information below can help you translate industry terminology and make you an informed shopper.

Energy Efficiency

First things first, make sure you are selecting an energy efficient brand. A simple way to discover this is to look for the ENERGY STAR®. Replacement windows that have earned the right to use this bright blue logo signifies that their products use less energy, help reduce your carbon footprint and best of all – help save you money.

Understanding the NFRC Label

Now that you have learn a little about ENERGY STAR certified products, it’s time to review the importance of NFRC ratings. ENERGY STAR certified windows or doors have been tested by the National Fenestration Rating Council (NFRC) and bear an NFRC label on them as proof. The NFRC is a third party, nonprofit organization that unbiasedly reports on windows and doors to help Eau Claire residents compare products and brands. This helpful label provides pertinent information about the ranking and rating of windows and doors. Here’s how to decode three important NFRC stats:

  1. U-factor
  2. U-factor is a phrase used in the construction trade to illustrate the sum of heat transferred through the structure of a building, including through windows and doors. In short, the U-factor informs you how efficient windows and doors insulate. U-factors range from .15 to 1.25; the lower number indicating the higher level of insulation. Remain cautious of extremely low U-factors that sound too good to be true. An artificially low rating was possibly from testing the center of a window pane. A more accurate way to tell is by referring to NFRC ratings, which consider the entire window or door unit.

  3. Solar Heat Gain Coefficient (SHGC)
  4. The SHGC measures the volume of heat from sunlight transfers through a window. The lower the SHGC rating, the less the window or door transmits solar heat. Usually, the SHGC rating ranges between 0.15 and .80. A high SHGC may provide some bonus heat in the winter months, but can also generate higher energy bills in the summer when Eau Claire homeowners compensated with air conditioning.

  5. Visible Transmittance (VT)
  6. The VT rating explains how much light transmits through a window. This may sound similar to what the SHGC expresses, but rather than heat from sunlight, the VT measures the actual light. VT becomes a factor when comtemplating how much sunlight you want in a particular space in your Eau Claire home. For example, a lower VT may be sought in a home theatre. The VT ranges from .02 to .80, with a higher number indicating more light transmission.

Other Window & Door Terms

Low Emissivity (Low E)

The term Low E refers to a microscopically thin metallic coating on a window. This process is done helps lower the U-factor and SHGC of a window. Low E windows and doors also provide an added benefit by reducing fading of furniture and carpet by blocking 70% to 95% of the ultraviolet rays.

Insulating Gas

Today’s windows and patio doors commonly include an insulating gas (argon) between panes to help in overall energy performance. Argon is nontoxic, nonreactive, clear, and odorless. When a window fogs up or becomes cloudy the seal has failed and the gas has dissipated from the window.

Learn more about quality replacement windows and doors by visiting the Eau Claire area Pella showroom.

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