---
title: "Short note: Lifts and escalators"
subject: "Building Technology"
chapter: 5
key: "semester_6/building_technology:short-lifts-escalators"
source: https://www.bctengineer.com/q/semester_6/building_technology/short-lifts-escalators
site: BCT Engineering
---

# Short note: Lifts and escalators

Building Technology · Chapter 5: Stair, lifts and escalators

- Asked in: 2066 Jestha (old course), 2.5 marks
- Video: [Lifts and Escalators, Conveyors - Machineries - Building Services and Repairs](https://www.youtube.com/watch?v=yOAJCEXAqLk) — Ekeeda
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/building_technology/short-lifts-escalators
- Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-5

## Question

Write a short note on lifts and escalators.

## Short answer

Lift: mechanical car in shaft for vertical transport, speeds 0.5-2.5 m/s, essential in high-rise. Escalator: moving stair with inclination 30 deg, capacity 4000-9000 persons/hour, used in malls/airports.

## Answer

#### Lifts
A **lift (elevator)** is a mechanical device which carries persons or goods between floors in a vertical shaft by a car moving on guide rails. Main parts: lift car, hoistway (shaft), guide rails, counterweight, wire ropes, traction machine and motor in the machine room (or machine-room-less), control panel, safety gear and buffers, landing doors and a pit. Types include passenger, goods, hospital (bed) and service lifts, with speeds of about 0.5-2.5 m/s depending on the building height. Lifts are essential in high-rise buildings and for disabled persons.

#### Escalators
An **escalator** is a moving stair: a continuous chain of steps driven by an electric motor, which carries a large number of people between floors at 0.5-0.65 m/s.
- Inclination 30 degrees (35 degrees max), step width 600, 800 or 1000 mm, capacity 4000-9000 persons/hour.
- Parts: truss, steps, step chain, handrail, comb plate, drive motor, balustrade and safety switches.
- Used in shopping malls, airports, railway stations and metro stations where heavy traffic moves continuously. It occupies more floor area than a lift and needs an emergency stair in addition.

| Point | Lift | Escalator |
|---|---|---|
| Movement | Vertical, in a shaft | Inclined moving steps |
| Capacity | 6-20 persons per trip | 4000-9000 persons/hour |
| Waiting | Waiting time | Continuous, no waiting |
| Space | Small shaft | Large floor opening |
| Suitable for | High-rise buildings, disabled persons | Malls, stations, airports |

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. How does a lift carry persons between floors?
   A. By a car moving on guide rails in a vertical shaft
   B. By continuously moving steps
   C. By an inclined belt
   D. By a rotating screw
   Answer: A. A lift is a car moving along guide rails in a hoist way. (Key point: Lift definition)

2. What is the usual inclination of an escalator?
   A. 15 degrees
   B. 30 degrees
   C. 45 degrees
   D. 60 degrees
   Answer: B. Escalators are normally inclined at 30 degrees (35 degrees maximum). (Key point: Escalator speed/slope)

3. Which is true when comparing lift and escalator?
   A. Lift gives continuous flow with no waiting
   B. Escalator needs a small shaft only
   C. Escalator carries 4000-9000 persons/hour with no waiting; lift carries 6-20 per trip
   D. Escalator is best for disabled persons
   Answer: C. Escalators give continuous high capacity; lifts carry few per trip and involve waiting. (Key point: Lift vs escalator)

4. Where is an escalator most suitable?
   A. Small houses
   B. Malls, airports and stations with heavy continuous traffic
   C. Wheelchair access in low buildings
   D. Warehouses for goods
   Answer: B. Its large continuous capacity suits places with heavy traffic; it also needs an emergency stair. (Key point: Escalator use)