Recent content by ichinoue

I am a bit confused about this in determining the velocity pressure exposure coefficient. The example given: the column height = 6m, roof truss height = 2.4m. The building is in a flat area.The height above ground (z) was solved as: z = 4.5 + (6-4.5)/2 = 5.25m question: where did 4.5m come from?