What must be large enough and in the right places to accommodate building movement from earthquakes?

What must be large enough and in the right places to accommodate building movement from earthquakes?

• A. Gaps or joints between cladding
• B. Foundation anchors
• C. Roof trusses
• D. Window openings

Answer: (A)

During an earthquake, the building shifts and there’s differential movement across the structure. The exterior finish must have places to accommodate that movement without cracking or pulling away from the frame. Gaps or joints between cladding provide space for this movement and are located where movement is expected—at transitions between materials, around openings, and at edges. They allow the façade to slide or flex slightly while staying attached and weather-tight, especially when filled with flexible sealants or designed expansion joints. Without these joints, the cladding can crack, buckle, or detach, leading to water intrusion and property damage. Foundation anchors keep the building tied to its foundation and don’t absorb envelope movement, while roof trusses and window openings aren’t meant to accommodate overall structural movement of the exterior.

During an earthquake, the building shifts and there’s differential movement across the structure. The exterior finish must have places to accommodate that movement without cracking or pulling away from the frame. Gaps or joints between cladding provide space for this movement and are located where movement is expected—at transitions between materials, around openings, and at edges. They allow the façade to slide or flex slightly while staying attached and weather-tight, especially when filled with flexible sealants or designed expansion joints. Without these joints, the cladding can crack, buckle, or detach, leading to water intrusion and property damage. Foundation anchors keep the building tied to its foundation and don’t absorb envelope movement, while roof trusses and window openings aren’t meant to accommodate overall structural movement of the exterior.