Floor numbering
In American English, in reference to typical buildings, the "first floor" is simply another name for the ground floor; but in British English, it means the floor above the ground floor. Hong Kong follows the British rule in English, but for some old tenant buildings the Chinese counterpart follows the American rule. Higher floors are then numbered consecutively in each case, as illustrated by the following table:
| British convention | American convention | Hong Kong convention |
| 3rd floor | 4th floor | 3rd floor (and 三樓, 四樓 (literally 4th floor) for old tenant buildings) |
| 2nd floor | 3rd floor | 2nd floor (and 二樓, 三樓 (literally 3rd floor) for old tenant buildings) |
| 1st floor | 2nd floor | 1st floor (and 一樓, 二樓 (literally 2nd floor) for old tenant buildings) |
| Ground floor | Ground or 1st floor | Ground floor and 地下 (literally Ground floor) |
| Basement | Basement | Basement |
It is obvious that this can lead to some confusion, but little else can be done other than being aware of this issue. See American and British English differences.
It is not uncommon for buildings to omit the number 13 in their floor numbering because of common superstition surrounding this number. The floor numbering may either go straight from 12 to 14, or the floor may be named something like 'Skyline' instead of numbered. See Thirteenth floor for more details. In Hong Kong some buildings would omit 4th, 14th, 24th, etc floor as the number 4 sounds like death in Cantonese, but the rule is varied.
To be merged:
taken from American and British English differences#Building layout
| Location | American English | British English |
|---|---|---|
| Bottom floor at ground level | First floor | Ground floor |
| One floor above ground level | Second floor | First floor |
| Two floors above ground level | Third floor | Second floor |
Put simply:
- American English floor number minus 1 = British English name
- British English floor number plus 1 = American English name
In North America, some buildings may have entrances on two different floors, such as those built into a hill. In these cases, the ground floor is the lower and the first floor is the upper.
Most European countries, countries of the Commonwealth, and former British colonies like Hong Kong, follow the same convention as the British, although Russia, some countries of East Europe, and Japan follow the American convention.
Some U.S. high-rise buildings follow the British system, often out of a desire on the part of the building's architect or owners to suggest a posh U.K./European setting.
(Floor numbering schemes in the USA sometimes skip the number 13 for the sake of the superstitious. In the UK, buildings of this height are less common anyway.)
taken from Elevator#Floor numbering
In general, elevator call buttons are numbered one-by-one to indicate the floors or landings that they cause the car to move to. However, there are some conventions to be aware of. The most important are:
- The differences in floor numbering between different cultures, such as the numbering system used by the USA and in China as compared with the conventions set by the British.
- Floor numbers considered unlucky may be skipped; the example, the floor above 12 may be numbered 14.
- The top level may be PH for Penthouse or, where applicable, R for Roof or O for Observation Deck.
- The ground floor may be G for Ground, M for Main, L for Lobby, or simply 1 (if it is also the first floor) or 0 (if not). As an aid to the visually impaired, there is often an embossed * beside the button.
- Below the ground floor is commonly B for Basement or P for Parking, sometimes L or LL for Lower Level.
- Below the basement may be SB for Sub-Basement. Numbered levels below ground, such as B1 or P1, are also common; the numbers may run either way, but B2 is usually below B1. Negative numbers (-1 for the first floor below ground, then -2, etc.) are also used, especially when the ground floor is numbered 0.
- Some buildings are just idiosyncratic; at one hotel in Toronto, the first six floors are labeled A, M, MM, C, H, and 1 (for Arcade, Main, Main Mezzanine, Convention, Health Club, and 1st floor).
- Floor designations sometimes vary between different banks of elevators in a building (due to its layout), or even between buttons and indicators in the same elevator (due to careless installation).
- Some elevators, especially in buildings with complex floor plans, have both front and rear doors that can open at the same floor; a second button with R appended to the floor abbreviation (e.g. GR or 2R) then requests a stop there with the rear door opening.
The convention that higher floors have their buttons placed higher may help resolve ambiguities, but many elevators have enough buttons that they are grouped in rows of two or even three.
In order to comply with laws regarding handicapped access, such as the Americans with Disabilities Act (ADA), a secondary button panel may be installed which is located at a height that can be reached by a person in a wheelchair. In this case the buttons may be arranged in a horizontal fashion.
On the elevator's position indicator, you may see the letters EZ. This is used to represent an Express Zone which is a long section of travel where the elevator makes no stops. Typically these are found in elevators that serve the upper reaches of tall buildings, thus bypassing several of the lower floors on the way.