Why does a pyramidal roof get the lowest wind uplift than a gable ended or hip roof?
Roof uplift is created in the negative pressure zone created by the movement of air over an edge delineating the boundry between two surfaces. The magnitude of the uplift is a product of 1) density of the air, 2) the velocity and angle of incidence of the air current and 3) the area and relative angle of the leeward surface of the roof. Maintaining the first two factors as equal when comparing roof geometries. The pyramidal roof is more successful in abating uplift because the geometry reduces both the area and relative angle of the leeward surface.
