I keep seeing new designs with valves in the ceiling just above every zone valve box in the building. The Service Valve belongs close to the Main Line or Riser and may control multiple zone valves on the same floor. This allows for backfeeding multiple zones from one location against this closed Service Valve.

Recently, I saw a future OR with valves in the ceiling just before and after the zone valves. It seems awfully expensive to have 3 times the number of necessary valves for a future zone.

Please explain this to the 6060 designer candidates when possible.