---
title: "Short note: Louvered and revolving doors"
subject: "Building Technology"
chapter: 6
key: "semester_6/building_technology:short-louvered-revolving-door"
source: https://www.bctengineer.com/q/semester_6/building_technology/short-louvered-revolving-door
site: BCT Engineering
---

# Short note: Louvered and revolving doors

Building Technology · Chapter 6: Doors and windows

- Asked in: 2081 Chaitra, 4 marks
- Video: [Types of Door (Part-1) | Classification of Doors | opening fixation in Building Construction](https://www.youtube.com/watch?v=9ysmz8msMak) — Decent T&C
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/building_technology/short-louvered-revolving-door
- Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-6

## Question

Write a short note on louvered doors and revolving door indicating their uses.

## Short answer

A louvered door has inclined slats that allow ventilation while blocking view and rain, used in bathrooms, kitchens, and stores. A revolving door has three or four leaves rotating around a central pivot, sealing against air loss; it is used in air-conditioned entrances such as hotels and banks.

## Answer

#### Louvered door
A louvered door has shutter openings fitted with inclined slats (louvres) at about 45 degrees, fixed between the styles. The slats keep out rain and block the direct view, yet allow air to pass. They are made of timber, steel or glass. The lower part may be panelled and the upper part louvered.

**Uses:** bathrooms, toilets, kitchens, store rooms, godowns and plant rooms, where both privacy and ventilation are needed.

#### Revolving door
A revolving door has three or four leaves (wings) fixed to a central pivot, which revolve within a circular enclosure (drum). People enter and leave by pushing the leaves round. At any time the leaves seal the opening, so very little air passes; heat loss from air-conditioned buildings is therefore reduced, and wind and dust are kept out.

```text
   PLAN
    ___ ___
   /   |   \
  |----o----|   4 leaves on central pivot
   \___|___/
```
**Uses:** hotels, banks, airports, malls and offices with air conditioning. A normal swing door is provided beside it for emergency exit and for wheelchairs and goods.

## Check yourself

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

1. Why are louvres inclined at about 45 degrees?
   A. To admit rain and sun
   B. To stop rain and direct view while allowing air
   C. To increase strength only
   D. To make the door lighter
   Answer: B. Inclined slats allow air but block rain and view, giving ventilation with privacy. (Key point: Louvre action)

2. Why does a revolving door reduce heat loss in air-conditioned buildings?
   A. It is made of insulated steel
   B. It stays permanently open
   C. It is always locked
   D. Its leaves always seal the opening so little air passes
   Answer: D. At any time the leaves close the opening, so little air passes and wind and dust are kept out. (Key point: Revolving door energy benefit)

3. What is provided beside a revolving door?
   A. A normal swing door for emergency exit, wheelchairs and goods
   B. A second revolving door
   C. A rolling shutter
   D. Nothing
   Answer: A. A swing door is provided beside it for emergency exit, wheelchairs and goods. (Key point: Emergency provision)

## Related in Building Technology

- [Types of doors by working mechanism](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Adoor-types-working) — Building Technology, chapter 6, asked 2×
- [General parts of doors and windows](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Adoor-window-parts) — Building Technology, chapter 6, asked 2×
- [Door/window components and door types](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Adoor-window-components-types) — Building Technology, chapter 6

## Related in other subjects

- [Two-room building: brick plinth, door shutters, plaster](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Abuilding-m-two-room-three-items) — Estimating and Costing, chapter 6
- [Multiplying factors for painting doors](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Amultiplying-factors-painting-doors) — Estimating and Costing, chapter 2