Elevator trips per day in a 30-floor office tower
A micro-operations estimate — peaks, batching, and round trips.
Estimate the number of elevator trips (door-close to door-open movements) per day in a 30-floor office tower with 6 elevators. The unit matters: trips ≠ passengers, because elevators batch people. This is a fully synthetic system — every number must be constructed.
Population
28 usable office floors × ~120 people ≈ 3,400 occupants + ~600 daily visitors.
Person-journeys
Arrive + leave (2) + lunch round trip (2) + meetings/breaks (~1.5) ≈ 5.5 × 3,400 ≈ ~19,000 journeys.
Batching
Peak cars carry ~10 people; off-peak ~2.5. Split journeys 60/40 peak/off-peak → 1,150 + 3,050 ≈ 4,200 loaded trips.
Empty trips
Elevators reposition empty (down at morning peak); add ~15–20% → ~4,800 trips/day.
Sanity
4,800 ÷ 6 cars ÷ 12 hrs ≈ 67 trips/car/hour ≈ one movement per minute — physically reasonable.
How to defend it
The counter-intuitive result to flag: off-peak generates more trips than peak because batching collapses. And always close synthetic builds with a physical-plausibility check (trips per car per minute) — it's the only external anchor available.