When getting a replacement window, you’ll see a label containing information on energy ratings on the product. Do you ever wonder what these ratings mean? These ratings are essential to homeowners, as they help them recognize the product’s level of energy efficiency. Let us discuss the importance of energy ratings in determining the efficiency of a window.



Let’s start with U-factor, which you see in your replacement windows. According to the National Fenestration Rating Council (NFRC), this rating measures the ability of the product to prevent heat from escaping a structure. This falls normally between 0.15 and 1.20. Keep in mind that the lower the value, the more effective the product is in keeping heat inside the home or building.

Solar Heat Gain Coefficient

Another energy performance indicator is Solar Heat Gain Coefficient or SHGC. This measures the amount of heat blocked from the sun. The value for SHGC is expressed between zero and one. If you see a window with lower SHGC, then it works well in stopping solar heat gain. Some homes, especially in the Northern areas may want more heat in their houses, so check with your local contractor.

Air Leakage

If you want to know how much air penetrates your home or building, check this measurement. Air leakage typically falls in between the values of 0.1 and 0.3. The lower the value in air leakage, the more effective the window keeps air out.

Visible Transmittance

Visible transmittance is responsible in checking how much light comes through your window. It is expressed in a range of zero and one. If your window has high values of visible transmittance, then you can enjoy more daylighting indoors.

Condensation Resistance

This rating measures how well a window resists condensation. Condensation resistance is expressed between 1 and 100. You will know your window resists condensation well if it has higher values of condensation resistance. Nonetheless, this is an optional rating.

These are the main categories of energy ratings. Make sure you’re getting an energy-efficient window by checking with your contractor on these ratings. EcoView® Windows & Doors is the go-to company for quality windows, doors, and hurricane shutters.

We ensure quality and performance in each of our installation. Our teams are experienced, licensed, and certified. For more information on our products and services, call us at (844) 216-7800. We’ll be ready to assist you.