Energy star labels and certifications are criteria used to determine energy-efficient products. It is set by the Environmental Protection Agency (EPA), aiming to save energy by reducing greenhouse gas emissions. When a product has the Energy Star Label, it has qualified or exceeded the standards set by the EPA. Energy star labels and certifications enable consumers to make informed decisions when purchasing a product. Similarly, business owners that sell Energy Star- Certified products earn trust from clients as they promote energy efficiency.

Why Prefer Energy Star Certified Windows and Doors?

Doors and windows that are Energy Star-Certified meet or exceed high energy efficiency standards. Doors and windows play a significant role in the cooling and heating of a home. Energy-efficient doors and windows save you from spending a lot on the energy bill. The Energy Star labels comprise U-value, SHGC, ER, and VT.

In some instances, Air leakage (AL), Condensation resistance(CR), the National Fenestration Certification, and CSA Certification. Some advantages of ENERGY STAR-certified windows are beneficial in the following ways:

  • They reduce your energy cost.
  • They help provide optimal temperature in your home.
  • Reduce condensation in low weather conditions.


U-value measures heat transfer into a building through a wall, window, or door. A window with good insulation shows a lower U-value. Conversely, when the U-Value of a window has a high U-value, it indicates that the window has poor insulation. The U-values range from zero to one, with low numbers indicating good window insulation and high numbers indicating poor window insulation.

SHGC (Solar Heat Gain Coefficient)

The solar heat gain coefficient estimates solar energy that comes in through the window. A high level of SHGC indicates more heat gain, while a low level of SHGC indicates low heat gain. Therefore, areas with a typical climate benefit from high SHGC as SHGC insulates the home. On that account, rooms with direct sun exposure are generally warmer than those with less sunlight. The SHGC of a home is determined by factors like window placement, climate, and shading, among others.

Energy Rating(ER)

The energy rating of a window is the overall energy performance of a window, taking into account its U-value, SHGC, and air permeability. A high Energy Rating value means that the window has high energy efficiency. Some advantages of installing windows with a high energy rating include improved energy efficiency in your room and help you save on energy. Additionally, you are confident that they meet all the regulations and are energy efficient.


VT, Visible Transmittance, is the amount of light transmitted through an insulated glass unit (IGU). Factors like gas fill, tints, glazings, and coatings on a window can reduce the VT rating. The VT of a window is not only measured by looking at the glass only. The window frame also determines the VT of a room. Also, the grids and window frame contribute to the window's VT. Windows with a thick grade and frame have a reduced VT.

ENERGY STAR Window Label Requirement

ES window label requirement is a removable label attached to a window to show that it is energy efficient. It entails:

  • A certified performance rating (U-factor, SGHC, and Energy rating)
  • Certification information
  • A removable sticker that indicates the manufacturer's name, model number, U-factor certification, the blue energy star logo, and the certification number, among others.
  • Type of model frame
  • Type of model operator
  • Its glazing type includes information like the number of glazed layers, and gas fills.
  • NRC number or model code
  • Testing warranty
Air Leakage

Air leakage is the heat loss or gain that happens through cracks or gaps in a window. The ENERGY STAR certification is given to windows with low air leakage(AL), usually 0.30 or less. AL hurts a building, including poor indoor air quality, low energy efficiency,  cold spots, high energy bills, and disruption of indoor temperature. Air leakage is not ventilation. AL can disrupt the ventilation in your home, and contractors should therefore reduce it. You can use materials like weather straps to minimize air leakage.

Condensation Resistance (CR)

Condensation Resistance is the ability of a window to resist condensation that occurs due to low temperatures. Windows with a high condensation rate experience condensation less often. Condensation can lead to eventual damage to the window. Factors that determine the CR include the room's temperature, humidity levels, the type of glass used, the window frame's design, and the window's condensation resistance. You can stop condensation in windows through weather stripping, opening your windows, and increasing the temperature in your home.


The R-value is also known as the thermal resistance rating. It is the measure of a material's ability to resist heat transfer. A high R-value indicates that a material has a high energy resistance. Insulating materials with a high R-value are more expensive than those with a low R-value since they help save on energy. Understanding the R-value in construction is essential in increased comfort for homeowners, purchasing the right windows, improved energy efficiency, and low operation costs.

Make Your Right Choice

The type of windows you purchase for your home is significant to your comfort and the amount of money spent on energy bills. Purchasing energy-efficient windows help you save significantly and provides optimal temperatures all year round.

Pay a consultant to help you determine the ideal windows for your home. Other factors you should consider before installing a window are the room's orientation, the climate of your residence, and the energy efficiency of the windows.

Also,  rooms that are too hot or cold indicate that your windows could not energy efficient. Therefore fixing or replacing your windows with more energy-efficient windows will enhance your comfort. With the advancement in window technology, there are windows like Low-emissivity glass windows and double-glazed windows that are more energy efficient.

May 30, 2023 — Della Wang