What are the three exposure categories for wind uplift?

What are the three exposure categories for wind uplift?

• A. Exposure B (urban/suburban), Exposure C (open terrain), Exposure D (coastal/large open water)
• B. Exposure A (urban), Exposure B (suburban), Exposure C
• C. Exposure C (open terrain), Exposure D (coastal), Exposure E
• D. Exposure B (coastal), Exposure C (open water), Exposure D (urban)

Answer: (A)

Wind uplift design depends on how sheltered the site is from wind, so exposure categories describe the level of shielding and openness around a structure. The three exposure categories used for wind uplift are urban/suburban, open terrain with scattered obstructions, and coastal or large open water areas. Urban/suburban areas have surrounding buildings that block or redirect wind, reducing uplift forces on a roof. Open terrain with scattered obstructions has fewer barriers, so wind can reach the roof more directly, giving intermediate uplift. Coastal or large open water areas provide the least shielding, with wind arriving more freely and producing the highest uplift pressures. This question uses those three categories to reflect the typical progression from most sheltered to least sheltered.

Wind uplift design depends on how sheltered the site is from wind, so exposure categories describe the level of shielding and openness around a structure. The three exposure categories used for wind uplift are urban/suburban, open terrain with scattered obstructions, and coastal or large open water areas. Urban/suburban areas have surrounding buildings that block or redirect wind, reducing uplift forces on a roof. Open terrain with scattered obstructions has fewer barriers, so wind can reach the roof more directly, giving intermediate uplift. Coastal or large open water areas provide the least shielding, with wind arriving more freely and producing the highest uplift pressures. This question uses those three categories to reflect the typical progression from most sheltered to least sheltered.