---
title: "General parts of doors and windows"
subject: "Building Technology"
chapter: 6
key: "semester_6/building_technology:door-window-parts"
source: https://www.bctengineer.com/q/semester_6/building_technology/door-window-parts
site: BCT Engineering
---

# General parts of doors and windows

Building Technology · Chapter 6: Doors and windows

- Asked in: 2077 Chaitra, 4 marks; 2076 Bhadra, 4 marks (asked 2 times)
- Video: [various parts of door and window](https://www.youtube.com/watch?v=W4nQXaAtLC4) — basic of civil engineering by vd
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/building_technology/door-window-parts
- Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-6

## Question

Show in figure the general parts used in door and windows (explain the various components of door and window with sketch).

## Short answer

Key parts of doors and windows include the frame (head, jambs, sill), shutter members (styles, rails, panels), and hardware. Additional terms: horn, mullion, transom, architrave, holdfast, and reveal.

## Answer

The general parts of doors and windows are shown below.

```text
 DOOR                              WINDOW
 +----------------------+          +------------------+
 | head                 |          |       head       |
 | +------------------+ |          | +------+-------+ |
 | |    top rail      | |          | |      |       | |
 | |------------------| |          | | sash | sash  | |
 | |s     panel      s| |          | |      |       | |
 | |t   lock rail    t| |   jamb ->| +------+-------+ |
 | |y     panel      y| |          |       sill       |
 | |l  bottom rail   l| |          +------------------+
 | +------------------+ |
 | threshold            |
 +----------------------+
```

#### Description of components
| Part | Description |
|---|---|
| Frame (chaukhat) | Fixed wooden/steel/RCC frame set in the opening; made of the head, two jambs (posts) and the sill/threshold |
| Head | Top horizontal member of the frame |
| Jamb / post | Vertical side member of the frame |
| Horn | Projecting end (100-150 mm) of the head/sill built into the wall |
| Sill / threshold | Bottom member (in windows) or floor-level strip (in doors) |
| Shutter | Movable leaf that closes the opening |
| Style | Vertical outer member of the shutter |
| Rail | Horizontal member of the shutter (top, frieze, lock, bottom) |
| Panel | Thin board or glass fitted in grooves between styles and rails |
| Mullion | Vertical member dividing a frame into two or more openings |
| Muntin | Intermediate vertical member between rails within a shutter |
| Transom | Horizontal member dividing a frame into upper and lower parts |
| Glazing bar | Thin member that divides a glass panel |
| Architrave | Moulded decorative cover over the joint between frame and wall |
| Holdfast | Metal strap fixing the frame to the wall |
| Hinge, bolt, lock | Fittings for hanging and closing the shutter |
| Reveal | Side surface of the wall opening |

## Check yourself

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

1. What is a horn?
   A. A metal strap fixing the frame
   B. A decorative cover over the joint
   C. A vertical member dividing the frame
   D. The projecting end of head or sill built into the wall
   Answer: D. The horn is a 100-150 mm extension of the head or sill built into the wall. (Key point: Horn)

2. Which member divides a frame into upper and lower parts?
   A. Transom
   B. Mullion
   C. Muntin
   D. Style
   Answer: A. A transom is horizontal; a mullion is vertical and divides a frame into side-by-side openings. (Key point: Mullion vs transom)

3. In a shutter, styles and rails are
   A. Horizontal and vertical respectively
   B. Both horizontal
   C. Vertical and horizontal respectively
   D. Fittings like hinges
   Answer: C. Styles are the vertical outer members; rails are the horizontal members. (Key point: Style and rail)

## Related in Building Technology

- [Door/window parts; casement, awning, hopper](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Adoor-window-parts-casement) — Building Technology, chapter 6
- [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
- [Thermal insulation of walls, doors, windows, roofs](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Athermal-insulation-exposed-walls) — Building Technology, chapter 1, asked 3×
- [Purpose and sizing of doors and windows; panelled doors](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Adoor-window-purpose-sizing) — Building Technology, chapter 6
- [Functions of door and window; battened door elevation](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Adoor-window-functions-battened) — Building Technology, chapter 6
- [Functions of openings; door and window types](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Aopenings-functions-working) — Building Technology, chapter 6

## Related in other subjects

- [Why Kaiser window is better than fixed windows](https://www.bctengineer.com/question.md?key=semester_7%2Fdigital_signal_analysis_and_processing%3Awhy-kaiser-better) — Digital Signal Analysis and Processing, chapter 5, asked 2×
- [Rate analysis: sal wood door/window frame per m³](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Arate-sal-wood-frame) — Estimating and Costing, chapter 4, asked 3×
- [RA: parts used in DBMS and MIS](https://www.bctengineer.com/question.md?key=semester_6%2Fdatabase_management_system%3Ara-parts-both-dbms-mis) — Database Management System, chapter 3
- [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