Vent: Any outlet for air that protrudes from the roof deck for instance a pipe or stack. Any system put in around the roof, gable or soffit for the objective of ventilating the underside with the roof deck. Batten: Also known as Purlins, see Purlin or Purloin. Batten or Purlins http://rowe-appliance-repairs00875.tblogz.com/the-smart-trick-of-metal-roofing-that-no-one-is-discussing-15082746