The U.S. Environmental Protection Agency has released the final draft of its Version 6.0 specification for Energy Star windows, doors, and skylights. Among the noteworthy changes in the latest proposal is a revised implementation date, with the new criteria now set to take effect January 1, 2015, rather than early 2014, as previously planned. 

Final changes
The draft maintains the 0.27 U-factor maximum for windows in the Northern climate zone that many in the industry argued was not cost effective, but the EPA did change some of the other U-factor requirements from previous drafts. EPA revised the U-factor maximum for windows in the North-Central Zone from 0.29 to 0.30. In addition, it is proposing that the U-factor maximum in the South-Central Zone be revised to 0.31 to 0.30 to simplify the specification for manufacturers.

The latest version of the criteria also includes air leakage labeling requirements, revised to allow existing certification labels in lieu of including an air leakage value on the National Fenestration Rating Council temporary label. The certification labels that can be used include:

• American Architectural Manufacturers Association
  Gold Label
• Keystone Certifications Inc. North American Fenestration Standard (NAFS) Structural Certification Label
• National Accreditation & Management Institute Inc. NAFS Structural Certification Label
• Window & Door Manufacturers Association Hallmark Certification Label

The air leakage requirements, which may also be furnished on an NFRC temporarly label, remain ≤ 0.3 cfm/ft² for windows, sliding doors and skylights and ≤ 0.5 cfm/ft² for swinging doors.

Other changes from previous Version 6 drafts include a revised to U-factor maximum for skylights in the Northern and North-Central Zones to 0.48. The change is designed to allow a greater number of products to qualify. EPA also made several changes to the installation instructions requirements, including a note that such instructions are not required on the product label and can be provided in the product packaging or online.

In addition to the final draft, EPA has issued a number of documents designed to explain various decisions and respond to input to date. These documents include an Introduction to Response to Comments, addressing several of the broader topics raised by commenters; a Response to Comments on Draft 2 Windows Criteria; a Response to Door and Skylight Comments; and aReview of Cost Effectiveness Analysis.

EPA is accepting comments on its final draft of the Energy Star Version 6.0 specification until August 21.  They can be submitted via email to [email protected].  It plans to finalize the criteria, now sheduled to take effect in 2015, in September 2013.