A storey (British English) or story (American English) is any level part of a building that could be used by people (for living, work, storage, recreation, etc.). The plurals are storeys and stories, respectively.
The terms floor, level, or deck can also be used in this sense; except that one may use "ground floor" and "ground level" for the floor closer to what is considered the ground or street level, whereas "storey" is commonly used only for levels strictly above or below that level The words "storey" and "floor" also generally exclude levels of the building that have no roof, even if they are used by people—such as the terrace on the top roof of many buildings.
Houses commonly have only a few floors, often only one. Buildings are often classified as low-rise, mid-rise, and high-rise according to how many levels they contain; but these categories are not well-defined. The tallest skyscrapers in the world have about a hundred floors (as of 2009).
The height of each storey is based on the ceiling height of the rooms plus the thickness of the floors between each. Generally this is around ten feet or three metres total, however it varies widely from just under this figure to well over it. Storeys within a building need not be all the same height — often the lobby is more spacious, for example. Higher levels may be smaller in area than the ones beneath (a prominent feature of the Willis Tower).
In English, the principal floor or main floor of a house is the floor that contains the chief apartments; it is usually the ground floor, or the floor above. In Italy the main floor of a home is usually above the ground level, and may be called the piano nobile ("noble floor").
The attic or loft is a storey just below the building's roof; its ceiling is often slanted and/or at a different height than that of other floors. A penthouse is a luxury apartment on the topmost storey of a building. A basement is a storey below the main or ground floor; the first (or only) basement of a home is also called the lower ground floor.
Split-level homes have floors that offset from each other by less than the height of a full storey. A mezzanine, in particular, is typically a floor halfway between the ground floor and the next higher floor. Homes with a split-level entry have the entire main floor raised half a story height above the street entrance level, and a basement that is half a storey below this level.
There are also multi-storey car parks, also known as parking garages.
Floor numbering is the numbering scheme used for a building's floors. There are two major schemes in use across the world. In one system, used for instance in the majority of Europe, the ground floor is the floor on the ground and often has no number or is assigned the number zero. Therefore the next floor up is assigned the number 1 and is the first floor. The other system, used in the United States for instance, counts the bottom floor as number 1 or first floor. The next floor up then becomes the second floor and so on. Having the first floor above the ground floor means that subterranean levels (often listed with increasing depth as B1, B2..) can be counted without having a gap at 0 (ground). In both systems, the numbering of higher floors continues sequentially as one goes up, as shown in the following table:
Displacement from ground level British convention American convention 3 storeys heights above ground "3rd floor" "4th floor" 2 storeys heights above ground "2nd floor" "3rd floor" 1 storey height above ground "1st floor" "2nd floor" at ground level "Ground floor" "Ground floor" or "1st floor"
Each scheme has further variations depending on how one refers to the ground floor and the subterranean levels. The existence of two incompatible conventions is a common source of confusion in international communication, sometimes even between communities who speak the same language.
In all English-speaking countries, however, the storeys in a building are counted in the same way. Thus, for example, the phrase a seven-storey building would mean the same thing in Britain and in the US — namely, a building with seven covered floors, including one at ground level and six at higher levels; even though the topmost of those levels would be called "6th floor" in Britain, and "7th floor" in the US. Some count mezzanines as storeys, some ignore them.
In most of Europe, the "first storey" or "first floor" is the level above ground level. This system is used in Denmark but not in the other Scandinavian countries This scheme is also used in many of the Commonwealth nations (except Singapore and most of Canada), many former British colonies, and in many Latin American countries, including Mexico and Brazil.
This convention can be traced back to Medieval European usage. In countries that use this system, the floor at ground level is usually referred to by a special name, usually translating as "Ground Floor" or equivalent. For example, rez de chaussée ("street level") in France, Erdgeschoss ("ground floor") in Germany, pianterreno (lit. "ground floor") in Italy, begane grond ("walked-upon ground") in Dutch, planta baja ("bottom floor") in Spain, andar térreo ("ground walkplace") in Brazil, "rés-do-chão" ("close to the ground") in Portugal, földszint ("ground level") in Hungary, parter ("based on French par terre which means along ground") in Poland, prízemie ("close to the ground") in Slovakia, and pritličje ("close to the ground") in Slovenia. In some countries that use this scheme, the higher floors may be explicitly qualified as being above the ground level — such as in Slovenian prvo nadstropje (literally "first upper floor").
US/North American scheme
The English-speaking parts of Canada generally follow the American convention, where the "first" floor is the floor at the ground level and the floor above it is the "second" floor. Canada however uses the spelling storey, not story. In Quebec, the European scheme was formerly used (as in France), but by now it has been mostly replaced by the US system; so that rez-de-chaussée and premier étage ("first stage") are now generally equivalent in Quebec. Mexico, on the other hand, uses the European system.
The US system is also used in Russia and some countries of the former Soviet Union, in Scandinavian countries except Denmark, and in some (but not all) Latin American countries. So, for example, planta baja and primer piso ("first floor"), which are distinct in Spain and Mexico, are equivalent in Chile and Peru, and refer both to the ground-level floor (although primer piso is used mainly for indoor areas, while planta baja is also used for areas outside the building).
Most countries in eastern Asia, including China, Japan, and Singapore, follow the North American system. In the grammar of the respective languages, the numbers precede the word "floor", and are cardinals rather than ordinals; so they would translate literally as "1 floor, 2 floor" (etc.), rather than "1st floor, 2nd floor", or "floor 1, floor 2".
In Singapore, the British system of numbering originally prevailed, but this was replaced in the 1980s with the North American scheme to avoid confusion with the Chinese scheme. In order to emphasise the difference from the original scheme, reference is frequently made to storeys or levels rather than floors) - so the 3rd floor is the 4th storey (or storey 4) or 4th level (or level 4). Many buildings continue to label storeys or levels rather than floors. Some time later, some newer buildings began to use 'floors' instead of naming them as 'storeys' or 'levels'.
Occasionally, buildings in the United States and Canada will have both a "1st floor" (usually the main floor of the building) and a "ground floor" below it. This typically happens when both floors have street-level entrances, as is often the case for hillside buildings. In the UK, the lower of these floors would be called the lower ground floor, while the upper would be called either the upper ground floor or simply the ground floor.
Sometimes, floor number 1 may be assigned to the lowest basement level; in that case the ground floor may be numbered 2 or higher. Sometimes two connected buildings (such as a store and its carpark) have incongruent floor numberings, due to sloping terrain or different ceiling heights.
In Sweden the floors are numbered as in the North American scheme ("1st" = "ground", "2nd", etc.); but one can also refer to them by how many flights of stairs one needs to climb to reach them from the ground floor. So, 2:a våningen ("2nd floor") is the same as 1 trappa upp ("1 stair up"); 3:e våningen ("3rd floor") is also 2 trappor upp ("2 stairs up"); and so on. In modern lifts, however, floors are numbered according to British convention, where the street level is referred to E (for "entré", or entrance) or BV (for bottenvåning, or bottom floor) and the next floor is given the number 1.
American and Canadian buildings typically omit the thirteenth floor 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 given an alternative name such as "Skyline". In certain Asian countries, some buildings (especially hospitals) may lack floors numbered 4, 14, 24, etc., due to the similarity in pronunciation between the words "four" and "death" in the respective languages. Some governments frown on the practice of skipping floor numbers and even building numbers.
In Hong Kong, the British numbering system is now generally used, in English and Chinese alike. In some older residential buildings, however, the floors are identified by signs in Chinese characters that say "二樓" ("2 floor") at the floor just above ground, as in the North American system. For those buildings, the Chinese phrase "三樓" or its English equivalent "3rd floor" may refer either to the storey three levels above ground (as in the modern numbering), which is actually labeled "四樓" ("4 floor"); or to the storey with the sign "三樓" ("3 floor"), which is only two levels above ground. This confusing state of affairs has led, for example, to numerous errors in utility billing. To avoid ambiguity, business forms often ask that storey numbers in address fields be written as accessed from a lift.
In some Chinese and Taiwanese buildings (typically high-rises), the 4th floor is actually omitted or skipped, with the floor above the third numbered as the fifth and so on. This is due to the Chinese word for "four" being very phonetically similar (though not exact homonyms in most dialects due to their intonations) to the word for "dead" or "die". Also for this reason, apartments on the 4th floor in Asian countries such as Taiwan have traditionally been cheaper to rent. This cultural superstition can be considered a form of tetraphobia.
In most of the world, elevator buttons for storeys above the ground level are usually marked with the corresponding numbers. In many countries, modern elevators also have Braille numbers—often mandated by law.
In countries that use the European system, the ground floor is either marked 0, or with the initial letter of the local word for ground floor (G, E etc.), successive floors are then marked 1, 2 etc. However, even when the ground floor button is marked with a letter, some digital position indicators may show 0 when the lift / elevator is on that floor. If the building also contains floors below ground, negative numbers are common. This then gives a conventional numbering sequence -2, -1, 0, 1, 2, 3, ...
Example: in Polish language there is a clear distinction: parter means ground floor, piętro means floor above parter, usually with ordinal: 1. piętro, 2. piętro etc., therefore parter is the zeroth piętro. Older elevators in Poland have button P for ground floor (parter) and S for basement (suterena). Elevators installed since 1990 have 0 for parter and -1, -2 ... for underground floors.
North American scheme
In countries that use the North American system, where "floor 1" is the same as "ground floor", the corresponding button may be marked either with 1, or with a letter, as in the European scheme. In either case, the next button will be labeled 2. In buildings that have both a "1st floor" and a "ground floor", they may be labeled 1 and G; or M (for "Main") and LM (for "Lower Main"). M may also be used to designate a mezzanine level, when it is not counted as a separate floor in the building's numbering scheme.
In modern signage, at least in North America, a five-pointed star (★) additionally appears beside the button for the "main entry" floor. In the United States, the five-pointed star marking is mandated by Title III of the Americans with Disabilities Act (ADA), as described in Section 4.10.12(2) of the ADA Accessibility Guidelines for Buildings and Facilities (ADAAG).
The numbering of levels below ground is also quite varied, even within the same country. In English-speaking countries, the first level below ground may be labelled B for "Basement", LL for "Lower Level" or "Lower Lobby", C for "Cellar", D for "Dungeon" in few buildings, or, in the case of the Andy Warhol Museum in Pittsburgh, U for "Underground". In British department stores, LG for "Lower Ground" is commonly encountered, as the term "basement" is considered inappropriate for their image.
If there is more than one basement, the next level down may be marked SB for "Sub-Basement". The lower levels may also be numbered B1, B2, etc.. Negative numbers are sometimes used −1 for the first level below ground, −2 for the second one, etc..
Elevator buttons may also be labeled according to their main function. In English-speaking countries, besides the common L for "Lobby", one may find P for "Pool" or "Parking" (and P1, P2, etc. for multiple parking floors), S for "Skyway", R for "Restaurant" or Roof, PH for "Penthouse", OD for "Observation Deck", etc.. In some US buildings, the label G on the elevator may stand for the building's "Garage", which need not be located on the "Ground" floor.
One hotel in Toronto marks the first six floors as A, M, MM, C, H, and 1 (for "Arcade", "Main", "Main Mezzanine", "Convention", "Health Club", and "1st floor"). The North Carolina Museum of Art, whose entrance is on the third floor up, has the floors lettered C, B, A (the main floor), and O (for "Office"). The Festival Walk mall in Hong Kong has floors labelled LG2 and LG1 ("Lower Ground 2" and "1"), G ("Ground"), and UG ("Upper Ground").
Romania uses Roman numerals for floor numbers in postal addresses, but Arabic numerals in all but the oldest elevators.
In modern buildings, especially large ones, room or apartment numbers are usually tied to the floor numbers, so that one can figure out the latter from the former. Typically one uses the floor number with one or two extra digits appended to identify the room within the floor. For example, room 215 could be the 15th room of floor 2 (or 5th room of floor 21), but to avoid this confusion one dot is sometimes used to separate the floor from the room (2.15 refers to 2nd floor, 15th room and 21.5 refers to 21st floor, 5th room) or a leading zero is placed before a single-digit room number (i.e. the 5th room of floor 21 would be 2105). Letters may be used, instead of digits, to identify the room within the floor—such as 21E instead of 215. Often odd numbers are used for rooms on one side of a hallway, even numbers for rooms on the other side.
An offset may be used to accommodate unnumbered floors. For example, in a building with floors labeled G, M, 1, 2, ..., 11 and 12, the 4th room in each of those floors could be numbered 104, 114, 124, 134, ..., 224, and 234, respectively — with an offset of 11 in the floor numbers. This trick is sometimes used to make the floor number slightly less obvious, e.g. for security or marketing reasons.
In Portugal, the rule (official standard) is:
- In buildings with only two sides, all the apartments are marked as Esq. (Esquerdo = Left) or Dto. (Direito = Right). So we have C/V Esq. (Underground Floor Left), R/C Esq. (Ground Floor Left), 1º. Esq (1st Floor Left), etc.; and C/V Dto. (Underground Floor Right), R/C Dto. (Ground Floor Right) 1º. Dto. (1st Floor Right), etc.
- Buildings with more than two apartments per floor, are marked with letters, clockwise within each deck. So apartment 8º-D (not 8D) means the 8th floor (hence the character "º" meaning ordinal number), apartment D (counting in clockwise direction, for those who are in the floor entrance). But a very common form for buildings with three apartments per floor is, Esq.-Frt./Fte. (Frente, en: Front - for the apartment located between left and right)-Dto.
These two rules, universally adopted, made many things easy, namely for blind people, who don't need to ask where is the apartment "X".
- ^ 
- ^ Rick Steves' Europe through the back door 2011
- ^ Politikens Nudansk Ordbog 15. edition ISBN 87-567-2107-9, see sal.
- ^ 
- ^ Perkins, Broderick (2002-09-13). "Bottom Line Conjures Up Realty's Fear Of 13". Realty Times. http://realtytimes.com/rtpages/20020913_13thfloor.htm. Retrieved 2008-04-14.
- ^ ADA Accessibility Guidelines for Buildings and Facilities (ADAAG), Section 4.10: Elevators
- ^ But P also stands for Parterre in some countries; http://onlinedictionary.datasegment.com/word/parterre.
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