The 2026 edition of AAMA/WDMA/CSA 101/I.S.2/A440, North American Fenestration Standard/Specification for windows, doors, and skylights (NAFS) has been published. This standard is the result of a multi-year effort by CSA Group, Fenestration and Glazing Industry Alliance (FGIA), and Window & Door Manufacturers Association (WDMA). An agreement among the three organizations requires NAFS to be reviewed every five years to keep current with changes in the fenestration industry. The updated 2026 standard supersedes the 2022 edition, representing a continued evolution of the standard while improving harmonization across North America. The Joint Document Management Group (JDMG), comprised of representatives from all three associations, stresses the importance of NAFS-26.
 
“Unlike with the previous version of NAFS, there were no major revisions for NAFS-26, with the exception of the secondary designator clarification,” said Lisa Bergeron, Director of Business Development and Government Affairs for JELD-WEN, who served as FGIA’s JDMG co-chair. “As it has been before, NAFS remains an excellent industry tool as an internationally accepted performance standard for the included fenestration product types.”
 

Clarification About a Secondary Designator

The primary change in NAFS-26 clarifies requirements for the secondary designator used in fenestration product ratings. The change was proposed by the Federal Emergency Management Agency (FEMA) and accepted following discussions with the JDMG.
 
Previously optional, the secondary designator is now mandatory and must be included on product test reports and labels. The secondary designator now requires performance values for:

• positive design pressure
• negative design pressure
• water penetration resistance test pressure

The change was driven largely by increasing concerns related to water intrusion performance, particularly in coastal and hurricane-prone regions such as Florida. FEMA’s proposal also aligned with recommendations previously raised by the Florida Building Commission.
 
“The JDMG held meetings with representatives from FEMA and came to agreement on how to address their concerns through NAFS,” said Robert Jutras, Chair of CSA’s Technical Committee and CSA’s JDMG co-chair. “The NAFS developers ultimately accepted the FEMA proposal.”
 

Code Adoption

“Since NAFS is a document that puts all the requirements for fenestration products in a single place, it has become a document that different code bodies have adopted,” said Dan Raap, Director of Product Testing and Compliance for AmesburyTruth, who served as WDMA’s JDMG co-chair. “It is referenced in the national building codes of both the U.S. and Canada through the IBC, IRC, IECC, and NBC. As states, provinces and territories adopt national codes, it becomes part of these more localized codes.”
 
The 2022 NAFS standard is already referenced in the 2024 editions of the International Building Code (IBC) and International Residential Code (IRC), and the recently released standard will be included in the 2027 editions of these codes. The 2022 NAFS standard is also referenced in the 2025 edition of the National Building Code of Canada, while the 2026 edition of NAFS will be proposed for inclusion in the NBC mid-cycle update. An equivalency document for NAFS-26 is expected to be developed later this year, providing guidance for compliance regarding testing to one version of NAFS versus another.
 

Purchasing Information

The 2026 edition of AAMA/WDMA/CSA 101/I.S.2/A440 is available online at CSA Group, Fenestration and Glazing Industry Alliance, or Window & Door Manufacturers Association.