Window Rating Labels

The National Fenestration Rating Council is responsible for window ratings. Using their updated website, you can leverage their  Window Selection Tool. The online tool searches a large database to help you find the best and most energy-efficient windows for your home and location’s climate. All their products are certified in their directory and contain clear energy efficiency labels.

The U Factor In Window Ratings

The U Factor in window ratings refers to the efficiency of the window and how well it contains heat. You should look for a lower rating, as this means that less heat is less likely to escape and offers better insulation. The U Factor will range between 0.20 and 1.20.

Condensation Resistance In Window Ratings

This component is optional for manufacturers to include and highlight on NFRC ratings. The condensation resistance measurement will show homeowners how likely it is for windows to build up moisture and condensation that can result in mold, damaged woodwork, and faded coloring.

The Condensation Resistance rating ranges between 1 and 100. In this case, you’re looking for the higher level, as it refers to how resilient a window is to condensation. The vast majority of ENERGY STAR windows come with high Condensation Resistance window ratings.

Visible Transmittance (VT)

Another core component of window ratings is Visible Transmittance. If you’re looking for lots of natural light, make sure to pay close attention to this particular window rating. Visible Transmittance window ratings will range between 0 and 1. A higher VT level for more penetrative daylight.

Air Leakage

Air Leakage is a window rating that measures how much air comes in via your window. Measuring in cubic feet in terms of how much air can pass through per square foot of your window area every minute.

This will impact the temperature and quality of the air in your home. On top of this, poor air leakage window ratings can be expensive to maintain and aren’t energy efficient. The lower the number, the less air leakage.

Solar Heat Gain Coefficient

The Solar Heat Gain Coefficient (SHGC) is a window rating that measures how effectively a window repels heat from the sun. This window rating is especially important for properties in hotter climates and will determine how often you may need to use your A/C.

The SHGC window rating will range between 0 and 1, and the lower the window rating, the lower your cooling bills will be during the peak heat season.

Use Window Ratings To Purchase Windows

Understanding window ratings is important when comparing different options. Once you understand what each of the ratings means and how to measure them, you’re free to pick a window choice that works best for your budget, household, and unique requirements. Call Perfect Choice Exteriors today with any window questions you may have.

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