How does Stick System Curtain Wall perform under wind load and seismic design requirements

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Stick system curtain walls can be engineered to meet stringent wind and seismic design requirements through careful selection of profiles, anchors, and connection detailing. For wind loads, the mullion and transom sizes are calculated to limit deflection and stress on glazing units; deflection limits are typically specified as L/175 to L/240 for glass to avoid damage or glass failure, and the design must resist negative and positive pressure cycles. Anchoring strategies — such as single-point, slotted, or pivot anchors — allow the curtain wall to transfer wind loads to the building structure while accommodating thermal movement. For regions subject to high wind events (hurricanes, typhoons), designers may specify laminated or thicker insulating glass units and reinforced mullions, and include drainage paths to prevent water ingress during deflection. Seismic performance requires connections that permit relative movement between the curtain wall and the primary structure. Seismic anchors and slip joints allow the façade to sway independently, preventing undue stress on glazing and silicone joints. Engineers commonly use finite element analysis to model dynamic responses and specify movement joints (vertical and horizontal) sized for code-required story drift. Additionally, stick systems are often designed with redundancy and capacity for cyclic loading to avoid brittle failure during seismic events. Compliance is verified through structural calculations, mock-up testing where necessary, and coordination with structural engineers to confirm that anchor loads and deflection tolerances align with the building’s seismic design category.