The Glass Framing Deflection Check Your Product Approval Never Ran: IBC 2403.3

A window can carry a legitimate PG55 rating, a state product approval, and a stack of AAMA/NAFS test reports — and still not satisfy Section 2403.3 of the International Building Code. The reason is a quiet gap between how fenestration products are rated and what the code actually requires: product ratings certify strength, while IBC 2403.3 limits stiffness — how far the frame bends at the design wind load. On coastal mid- and high-rise projects from Texas to the Carolinas, it is one of the most consequential little-known checks in Chapter 24 of the code.