Which roof area is typically associated with the highest wind pressure?

• A. Center zone.
• B. Edge zone.
• C. Corner zone.
• D. Ridge zone.

Answer: (C)

The strongest wind-induced uplift on a roof usually occurs where two roof edges meet—at the corners. When wind flows around a building, it creates complex three-dimensional flow with corner vortices forming in the corner zones. These vortices intensify suction on the roof surface, producing the highest local wind pressure there. The center of the roof is relatively sheltered by the surrounding roof area, and while the edges experience significant uplift, it’s typically less extreme than at the corners. Ridge areas can have elevated uplift on certain roof shapes, but for a rectangular or standard roof, corner zones exhibit the peak pressures due to the combined effect of two converging edge interactions.