--- title: "Door/window components and door types" subject: "Building Technology" chapter: 6 key: "semester_6/building_technology:door-window-components-types" source: https://www.bctengineer.com/q/semester_6/building_technology/door-window-components-types site: BCT Engineering --- # Door/window components and door types Building Technology · Chapter 6: Doors and windows - Asked in: 2068 Baisakh (old course), 8 marks - Video: [Technical Terms in Windows, Doors & Ventilators | Building Construction](https://www.youtube.com/watch?v=dFyxYwn663Q) — SGK Online Education - 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-components-types - Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-6 ## Question What are the different components of doors and windows, explain with necessary sketches. Explain the different types of doors with the help of sketches. ## Short answer Doors and windows consist of a fixed frame (jambs, head, sill, horns, holdfasts) and movable shutters (stiles, rails, panels, glazing bars) with fittings (hinges, bolts, locks). Window frames include mullions/transoms; sills have slope and drip groove. Door types: battened/ledged, battened/ledged/braced, framed/panelled, flush, glazed, louvered, sliding, folding, revolving, rolling shutter, swing. Each suits specific uses like stores, houses, shops, hospitals, godowns. ## Answer A door or window is made of a fixed **frame** and one or more movable **shutters**, together with fittings. #### Components of doors - **Frame (chaukhat):** the fixed assembly in the wall that carries the shutter. Parts: vertical *posts (jambs)*, horizontal *head* (top) and *sill* (bottom, in windows and some doors). - **Shutter:** the movable leaf that opens and closes the opening. Parts: *stiles* (vertical), *top, middle (lock) and bottom rails*, *panels*, *glazing bars* and *muntins*. - **Horns:** short projections of the head/sill that are built into the masonry to hold the frame. - **Holdfasts:** MS flats (about 30 x 6 mm, 20 cm long) fixed to the frame sides and embedded in the wall/concrete. - **Architrave and lining:** a moulded finishing strip around the frame and a board lining the reveal. - **Fittings:** hinges, tower bolts, aldrop, handle, lock, stopper, door closer, glass and putty. ```text Frame in wall (section) Part of shutter wall | horn ____________ ==== |==HEAD=== |__top rail_| holdfast->| | |s| |s| POST | | |t| pane |t| | | |i| |i| |_|_bottom_| ``` #### Components of windows - **Frame:** posts (jambs), head, sill, and mullions/transoms in larger windows. - **Sash/shutter:** the openable glazed part, with stiles, top and bottom rails, glazing bars and a lock rail. - **Sill:** the bottom member, with a slope and a drip groove (throating) to throw rainwater out. - **Mullion and transom:** vertical and horizontal members that divide a large opening. - **Glass panes, putty/beading, hinges, handles, stays, bolts and window bars/grill.** ```text +-----------------+ HEAD | sash | sash | | (glass)|(glass) | <- MULLION between |--------+--------| <- TRANSOM | sash | sash | +-----------------+ SILL (sloped, drip groove) ``` #### Types of doors | Type | Main features / use | |---|---| | **Battened and ledged** | Vertical boards joined by 2-3 horizontal ledges; cheap; stores, sheds | | **Battened, ledged and braced** | Diagonal braces added to prevent sagging; wider doors | | **Framed and panelled** | Stiles and rails with panels of wood/plywood/glass; houses, offices | | **Flush door** | Plain smooth faces over a timber frame and core (hollow or solid); modern rooms | | **Glazed door** | Panels replaced by glass; shops, offices | | **Louvred door** | Slats fixed in the frame; ventilation in bathrooms, toilets | | **Sliding door** | Moves on rollers/tracks; saves swing space; shop fronts, garages | | **Folding / collapsible door** | Hinged leaves fold; garages, shops (steel collapsible gate) | | **Revolving door** | Four leaves on a central pivot; hotels, banks, air-conditioned halls | | **Rolling shutter** | Interlocked steel slats roll on a drum; shops, godowns | | **Swing / double-action door** | Opens both ways; hospitals, kitchens | ```text Battened & ledged Framed & panelled Flush door +------------+ +------------+ +------------+ |||||||||||||| | panel | | | |============| ledge |------------| | plain | |||||||||||||| | panel | | skin | |============| ledge |------------| | | |||||||||||||| | panel | | | +------------+ +------------+ +------------+ ``` ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. What is the function of a holdfast? A. Hold the glass in the sash B. Fix the frame to the wall by embedding MS flats in masonry/concrete C. Lock the shutter D. Throw rain water off the sill Answer: B. Holdfasts are MS flats (about 30 x 6 mm) embedded in the wall. (Key point: Holdfast) 2. Why is a drip groove (throating) cut in the window sill? A. To hold the putty B. To fit the hinge C. To throw rain water away from the wall D. To allow ventilation Answer: C. The sloped sill with a drip groove sheds water outward. (Key point: Sill throating) 3. What are mullions and transoms? A. Hinges and bolts B. Parts of the louvre C. Types of shutter glass D. Vertical and horizontal members dividing a large opening Answer: D. Mullion is vertical, transom is horizontal. (Key point: Mullion vs transom) 4. Where is a battened and ledged door suited? A. Stores and sheds, being cheap B. Hotels with air conditioning C. Hospital corridors D. Shop fronts needing display Answer: A. It is a cheap door for stores and sheds. (Key point: Battened and ledged door) ## Related in Building Technology - [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× - [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 openings; door and window types](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Aopenings-functions-working) — Building Technology, chapter 6 - [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 - [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 ## 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× - [How symmetrical components help analysis](https://www.bctengineer.com/question.md?key=semester_5%2Fpower_system_analysis_ii%3Asymmetrical-components-unbalance-help) — Power System Analysis II, chapter 4 - [Bridge site factors and components with sketches](https://www.bctengineer.com/question.md?key=semester_7%2Ftransportation_engineering_ii%3Abridge-site-factors-components-sketches) — Transportation Engineering II, chapter 5