This picture shows venting from the left side horizontally 20 ft (second of three total wall penetrations) then vertical 30 ft to outside wall termination which is 14 ft off of ground level.  All of this pipe is double wall AL294C special gas vent.  To see the boilers this pipe is venting click http://www.dmstorrschimney.com/our-soot-stories/franklin-institute-boston-part-1-