This building form goes back to early history as early Christian worship halls. The high center was the gathering space for liturgical proceedings and the lower adjacent, side flanking spaces contained supportive activities and extra seating. This later developed into the cathedral forms. The basic profile also became useful in American agriculture because the centered, second story loft stored hay and one could unload to a wagon below. The side-flanking sections roofs gave stability to the center loft and also provided extra storage space. Early industry picked up on this basic form as well but with different functionality. The center raised roof created side fenestration called clerestory windows and this brought needed natural lighting (and ventilation) into the center of very large factory buildings, before electric lighting was used. This monitor form has imprinted in our history so well that most of us see this as a familiar shape.
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