SIZE: Doors are primarily designed for humans, sometimes exclusively for passage of goods and animals, but more often sized for all purposes. The size of a door is in relation to: the proportion of the inside room space, fore-space, architectural schema, etc. besides the functional needs of transit, transport, exchanges of environmental elements (breeze, heat, energy etc.) vision across (framing), sound leakage and ingress, illumination, participation, privacy, etc.
The economics and the technology are two main conditioners for the size of a door, though not restrictive factors. Doors of extra ordinarily large sizes or monumental proportions have been used through ages. A large door denotes unrestricted transit or reception, fearlessness or power, affluence, and dominance.
The size of a door is also referential, and so contextual structures are conceived to enhance the perceived size of a door. Doors of smaller sizes than nominally necessary, are used to slow down and thereby control and check the chaotic traffic of entrants. Doors are intentionally made smaller, if these are insignificant, or need to be concealed, such as the secret or escape doors. Smaller doors are stronger, but not necessarily easier to open or shut. Smaller width openings increase the integrity of the load-bearing structure.
The size of a door is also governed by the architectural scheme of the built mass and its relation with the surroundings. Fort gates and other gateways have not only large doors but also have elaborate structures like abutments, ramparts, bulwarks, bastions, bastilles, battlements, belvederes (Chhatri), buttress, campaniles (bell towers). These appended structures increase the significance of the opening.
Historically, very wide doors have been a necessity, for functional passage as well as for splendour. Wide door or gate openings are provided for ceremonies, processions, etc. Wide doors, however, are incapable of regulating the traffic. Such openings need either barricades to channelize the traffic, or multiple narrower door systems.
Tall doors were less of the functional requirements, but a compulsion in monumental structures, with royal or public patronage. For very tall doors, the construction of strong shutter and relevant opening control mechanism have been the greatest deterrent. Tall opening like effects are created with architectural door portals, where the functional door is very much smaller.
Large doors require lateral stiffening, as the usual thin shutter leaf construction is insufficient against buckling forces such as the wind, blasts, and often sonic boom pressures. Aircraft hangers’ and spaceships’ assembly workshops (Apollo, Columbia, USA) have very large doors with additional lateral framing. Similarly dams and canal gates have to resist not only the pressure of retained water but dynamic pressures of waves and eddy currents. Such doors are designed as a 3D entities. Stadia and such public spaces where people are likely to push the gates, extra lateral stability is required.
Traditionally doors have had a vertical form. The vertical rectangular form makes the opening taller then its width. It reduces the load on the hanging devices such as hinge or pivot, and so easy to open. The smaller width doors are technologically more efficient to construct and operate. Doors with two shutters divide the door further, and create a narrower version.
The width of a door is decided primarily on functional passage needs, but any heights above human head level (or with the head loads) are extravagance. Width of a door determines the density of traffic and the size of articles that can pass through it. Industrial doors are conceived for passage of goods and lifting mechanisms. Sliding doors have easier handling if are wider then their heights.
Proportions of doors relate to the architectural design. Most common set of proportions (Width: Height) have been: Two squares 1: 2, or Golden proportion 1:1.61. Height of a door is determined by the architectural requirements, but width of a door is in proportion to its height.
Some famous doors’ proportions are: Treasury of Atreus, Mycenae 9′-0” x 18′-0″, Parthenon, Rome 0′-0″ x 24′-2″, Erechtheion, Athens 8′-0″ x 17′-2″, S. Martin, Worms 5′-8″ x 11′-3″, Palazzo Pietro Massimi, Rome, main entrance door 6′-10″ x 13′-8″.
Actual width or width of passage is less for door openings set with architectural door surrounds, compared to wood framed and hinged doors. Pivots other than at the extreme corner of a shutter restrict the nett opening available.
In modern times, as a social concern, it is essential to provide doors widths suitable for disabled persons, such as using walking sticks, crutch, a walker, a wheel chair, stretcher or assisted by others. Width of a door for, toilets, elevators, closets, store rooms, change rooms, and such other lone user utilities are considered very critical for ergonomic profiles of such users.
Simple sliding doors allow very exact control over the width of opening. Automatic sliding doors such as for elevators and for entrances of public buildings automatically open to width governed by the density and frequency of traffic. Revolving doors have optimum opening size to maintain the air lock and prevent anyone forcing a reverse movement. Folding shutter doors allow incremental width of the opening. Garage doors sliding up were designed to get a maximum unhindered width of opening.
Height of a door is designed with three parameters: 1. the height available within the opening, 2. the height of the door head, and 3. the height of the threshold. The actual passage height of a door is acutely affected by the level of terrain immediately inside and outside the door. Low level doors have been used to reduce the heat gain or loss (e.g. igloos), the storm water entry (e.g. sea front warehouses in America).
A threshold protects the interior from dust, rain or snow storms, however, a taller threshold reduces the door passage height. A high threshold makes a door little less functional for entry-exit, and takes it closer to the identity of a window. French windows are only high threshold doors.
Egyptian temples had very tall openings, the lower section was shuttered and the upper section was a gap. Gothic churches had upper section of the door converted into a rose window. Very tall doors, unless required for passages are turned into transom lites. Very tall doors require a visual correction. Romans constructed tall doors with a wider base and narrower top.
These are dimensions, recommended for Human passage through a Door. The size in brackets show adjusted sizes as per ISO modulation system of @100x mm.
1 Height of Indian Male without head load or raised hand
@ 95 percentile 1751 mm (1800mm optimum)
2 Height of Indian Female without head load or raised hand
@ 95 percentile 1615 mm (1700mm optimum)
3 Height of common Indian (M+F combined factor)
@ 95 percentile 1741 mm (1800mm optimum)
4 Erect stature of common Indian (M+F)
@ 95 percentile 1771 mm (1800mm optimum)
5 Raised hand of common Indian (M+F)
@ 95 percentile 2289 mm (2300mm optimum)
6 Width of Indian Male
@ 95 percentile 619 mm (700mm optimum)
7 Width of Indian Female
@ 95 percentile 599 mm (600-700 mm optimum)
8 Width of common Indian (M+F combined factor)
@ 95 percentile 619 mm (700mm optimum)
9 Sideways width of Indian Male
@ 95 percentile 409 mm (500mm optimum)
10 Sideways width of Indian Female
@ 95 percentile 439 mm (500mm optimum)
11 Sideways width of common Indian (M+F combined factor)
@ 95 percentile 419 mm (500mm optimum).