Exposure B: For buildings with a mean roof height of less than or equal to 30 ft (9.1 m), Exposure B shall apply where the ground surface roughness, as defined by Surface Roughness B, prevails in the upwind direction for a distance greater than 1,500 ft (457 m).
This factor shall only be applied when used in conjunction with load combinations specified in Sections 2.3 and 2.4.
