Wind and pressure differentials exert a strong force on large doors. In applications where wind or a strong pressure differential may act on the door, select a model designed to maintain effective sealing under these conditions. Overhead segmented doors have the greatest ability to resist wind and air pressure. At the other extreme, horizontally rolling and folding doors have the least resistance, tending to blow apart where the two halves meet in the middle. Magnetic seals can substantially improve sealing by these types, up to a point where the magnets cannot hold the two halves of the door together. Vertically rolling doors resist wind and pressure up to a point, but they jam or blow open above their maximum
pressure tolerance. Some models of vertically rolling doors offer limited reinforcement to resist pressure.