The U.S. Environmental Protection Agency (EPA) released the latest proposed criteria for its Energy Star Most Efficient program for 2020, including windows. EPA will hold a stakeholder webinar on August 7, from 2-4 p.m. Eastern to discuss the proposed changes. Interested parties can register on EPA’s website.
Windows and sliding glass doors (NFRC operator type DDSG) for residential buildings are eligible for Energy Star Most Efficient 2020 recognition. The following products are not eligible:
- Windows for commercial buildings;
- Doors (except sliding glass doors with );
- Skylights; and
- Tubular daylighting devices.
Eligible products must be Energy Star certified consistent with applicable Energy Star Partner Commitments and the requirements set forth in the latest version of the Energy Star Program Requirements and Eligibility Criteria for Windows (or doors for sliding glass doors), according to the EPA.
Product performance (U-factor and solar heat gain coefficient ratings) must be certified by a certification body recognized by the EPA. Products also must be independently certified to meet the North American Fenestration Standard/Specification (NAFS) with a performance grade of greater than or equal to 15. NAFS certification does not require an EPA-recognized certification body.
Finally, products must meet the applicable requirements shown below:
| Climate Zone | U-factor | Solar Heat Gain Coefficient (SHGC) |
| Northern | ≤ 0.20 | ≥ 0.20 |
| North-Central | ≤ 0.20 | ≤ 0.40 |
| South-Central | ≤ 0.20 | ≤ 0.25 |
| South | ≤ 0.20 | ≤ 0.25 |
Upon review and approval of product applications received from Energy Star Partners, EPA will add qualifying models to the Energy Star Most Efficient 2020 products list for windows from January 1, 2020, through December 31, 2020.
The Energy Star Most Efficient 2020 designation may be used in association with window products recognized during this period for as long as the model remains on the market.