The FGIA Virtual Summer Summit brought together leading specialists from across the fenestration industry to examine key technical developments shaping window and façade performance. Through expert-led sessions, participants explored sealant compatibility, architectural glass engineering and the newly released NAFS-26 standard, gaining practical insights into improving product durability, testing and compliance.

One of the summit’s most technical discussions focused on sealant selection and compatibility within insulating glass units (IGUs). During the panel session, Steve Altum of Dow Performance Silicones, Lori Dahlman of Bostik and Brandon Rhoades of H.B. Fuller explained how sealant performance directly influences long-term system reliability. Rhoades highlighted the functional differences between single- and dual-seal IGUs, emphasizing that dual-seal systems combine a primary moisture and gas barrier with a secondary structural sealant that provides mechanical strength, while single seals remain suitable only for non-structural glazing applications.

Dahlman addressed back bedding sealants used to bond glazing to window frames, noting that AAMA 800 remains the industry’s benchmark specification for these products. She encouraged manufacturers to report field sealants that fail prescribed testing so performance requirements can continue to evolve. Altum stressed that selecting structural sealants requires careful consideration of project-specific conditions, including design loads, climate and application requirements, while emphasizing close collaboration with sealant suppliers to achieve optimal adhesion.

Architectural glass design was another major focus. Dr. Stephen Morse of Michigan Technological University explained how glass thickness, dimensions, aspect ratio and support conditions influence load resistance and breakage probability. Referring to ASTM E1300, he outlined its role in determining wind load resistance for monolithic, laminated and insulating glass systems, while revealing ongoing research into vacuum insulating glazing units supported by FGIA and the National Glass Association.

The summit also examined the implementation of NAFS-26, released on June 1. Experts Lisa Bergeron, Robert Jutras and Dan Raap explained that the updated standard now makes the secondary designator mandatory for product labels and test reports, requiring positive and negative design pressure values alongside water penetration resistance.