The 2026 edition of the North American Fenestration Standard (NAFS-26) has officially been published, bringing updated requirements for the testing, rating, and labeling of windows, doors, and skylights across North America. Developed jointly by the CSA Group, Fenestration and Glazing Industry Alliance, and Window & Door Manufacturers Association, the standard reflects a multi-year review process designed to keep pace with evolving industry needs and building performance expectations.

Under a long-standing agreement between the three organizations, NAFS undergoes a comprehensive review every five years. The newly released NAFS-26 supersedes the 2022 edition and maintains its role as the primary performance standard for fenestration products throughout North America.

According to industry leaders involved in the revision process, the most significant update in NAFS-26 is the clarification and mandatory adoption of the secondary designator used in product ratings. Previously optional, the secondary designator must now appear on all product test reports and certification labels.

The revised requirement mandates the disclosure of three key performance metrics: positive design pressure, negative design pressure, and water penetration resistance test pressure. These values provide a more complete picture of a product’s structural and weather-resistance capabilities, allowing architects, builders, code officials, and consumers to make more informed decisions when selecting fenestration systems.

The change originated from a proposal submitted by Federal Emergency Management Agency and was ultimately adopted following extensive discussions with the Joint Document Management Group (JDMG). The proposal was driven by growing concerns over water intrusion performance, particularly in coastal regions and hurricane-prone areas such as Florida, where severe weather events place increasing demands on building envelopes.

Industry officials note that the update also aligns with recommendations from the Florida Building Commission. By making the secondary designator mandatory, NAFS-26 aims to improve transparency, enhance product performance evaluation, and strengthen resilience standards for modern buildings.