Ballowing_When wind rushes over the edge of a building, it creates vortexes of wind, like mini tornadoes.  These wind vortices cause pockets of low pressure to develop above the roof surface.  The air inside the roof system has a higher pressure relative to the air above the roof when the wind is blowing. So the pressure differential causes the ballooning_Ballooning stresses the membrane causing it to stretch and wear more quickly. Umbrella Shop, Roofing Systems, Tornadoes, Commercial, Stress, Surface, Pockets, Mini, Building