Lift Count Calculator
How many lifts a building needs — from its population, floors and the peak five-minute handling capacity a lift bank must deliver — and the interval between cars that results.
Lift design is sized on the morning up-peak: the share of the building population that arrives in the busiest five minutes, typically 12 to 15% for an office.
How the lift count calculator works
Lift design is sized on the morning up-peak: the share of the building population that arrives in the busiest five minutes, typically 12 to 15% for an office. Each lift carries a certain number of people per round trip, and a round trip takes longer the more floors it serves.
The two figures that matter are handling capacity — can the bank move the peak — and interval, the average wait between cars, which should be under 30 to 40 seconds for a good office.
Formula: lifts = peak 5-min demand / (people per trip × trips per 5 min)
Worked examples
| Inputs | Lifts needed | Note |
|---|---|---|
| 1,200 people over 14 floors | 6 | six lifts |
| A smaller building | 2 | two lifts |
| A stricter interval | 6 | more lifts for waiting time |
FAQFrequently asked questions
How many lifts does an office need?
Roughly one per 150 to 250 people for a mid-rise, but it depends on floors, car size and the interval you want. This computes it from the peak rather than a rule of thumb.
What is handling capacity?
The share of the building population the lifts can move in five minutes. Twelve to fifteen per cent is the office standard; residential can be lower.
What is interval?
The average time between cars arriving at the lobby. Under 30 seconds is excellent, 40 acceptable; beyond that people notice the wait.
What sets the round-trip time?
Floors served, stops per trip, door times and speed. A 14-floor office with a 1.6 m/s lift takes about 150 seconds; taller or slower takes longer.
Is this a traffic analysis?
It is the first-pass sizing a traffic analysis refines. Destination dispatch, zoning and sky lobbies all change the answer for tall buildings.
Where these figures come from
- Sabine (1922) — Collected Papers on Acoustics — the reverberation-time equation
- CIBSE Guide A — Environmental design — daylight, comfort and ventilation criteria
- Neufert — Architects' Data — the standard reference for space and dimension
- International Code Council — International Building Code — occupant load and egress factors
- Australian Building Codes Board — National Construction Code — the body that writes Australia's building code
Last checked: September 2026. Formulas are the standard building-science and code relationships; default thresholds are common international values and should be replaced with the ones in your code.