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Energy Efficient Windows

What should I look for when buying windows and doors?

Every ENERGY STAR window and door is independently certified to perform at levels that meet or exceed energy efficiency guidelines set by the U.S. EPA. But how do you know which windows work in your climate? The following tips will help you buy with confidence.

Purchasing Tips

Shopping for new windows and doors can be a confusing process. ENERGY STAR makes it simple! Follow these five steps to ensure your windows and doors deliver savings and comfort you'll enjoy.

  • Determine your ENERGY STAR Climate Zone.
  • Find a retailer of ENERGY STAR certified windows or doors.
  • Look for the ENERGY STAR label for your climate zone. All ENERGY STAR certified products must display the ENERGY STAR label. Check the label to make sure the product you are considering is certified to meet the criteria for your area. The ENERGY STAR label appears on the product next to the National Fenestration Rating Council (NFRC) label.

How a Product Earns the ENERGY STAR Label?

What is ENERGY STAR?

ENERGY STAR is the trusted, government-backed symbol for energy efficiency helping us all save money and protect the environment through energy-efficient products and practices.

The ENERGY STAR label was established to:

  • Reduce greenhouse gas emissions and other pollutants caused by the inefficient use of energy; and
  • Make it easy for consumers to identify and purchase energy-efficient products that offer savings on energy bills without sacrificing performance, features, and comfort.

How Does EPA Choose which Products Earn the Label? 

Products can earn the ENERGY STAR label by meeting the energy efficiency requirements set forth in ENERGY STAR product specifications. EPA establishes these specifications based on the following set of key guiding principles:

  • Product categories must contribute significant energy savings nationwide.
  • Certified products must deliver the features and performance demanded by consumers, in addition to increased energy efficiency.
  • If the certified product costs more than a conventional, less-efficient counterpart, purchasers will recover their investment in increased energy efficiency through utility bill savings, within a reasonable period of time.
  • Energy efficiency can be achieved through broadly available, non-proprietary technologies offered by more than one manufacturer.
  • Product energy consumption and performance can be measured and verified with testing.
  • Labeling would effectively differentiate products and be visible for purchasers.

How Does EPA decide when to Revise Specifications? 

Generally, a market share of ENERGY STAR certified products in a particular category of 50 percent or higher will prompt consideration for a specification revision.  However, there are other factors that weigh into the decision, such as:

  • A change in the Federal minimum efficiency standards.
  • Technological changes with advances in energy efficiency which allow a revised ENERGY STAR specification to capture additional savings.
  • Product availability
  • Significant issues with consumers realizing expected energy savings
  • Performance or quality issues
  • Issues with Test Procedures