Thirteenth floor

The levels of a multi-story building are numbered sequentially, from "basement", "one" or "ground" upwards. In some countries, the number 13 is considered unlucky and building owners will sometimes purposefully omit a floor so numbered.cite web|url=http://www.washingtonpost.com/wp-dyn/content/article/2007/08/18/AR2007081800890.html|title=The 13th Floor: A Ghost Story|last=Fleischman|first=Sid |publisher=The Washington Post Company|accessdate=2008-07-26] Hence, the 13th floor is given the number 14. Even landlords who are not themselves superstitious realize that the desirability of suites on a floor 13 might be compromised because of superstitious tenants, or commercial tenants who worry about losing superstitious customers. Based on an internal review of records, Dilip Rangnekar of Otis Elevators estimates that 85% of the buildings with their elevators do not have a named 13th floor. [cite web
url=http://realtytimes.com/rtpages/20020913_13thfloor.htm
title=Bottom Line Conjures Up Realty's Fear Of 13
last=Perkins
first=Broderick
publisher=Realty Times
date=2002-09-13
accessdate=2008-04-14] Also the disney ride The Twilight Zone Tower of Terror is known to have 13 floors, even though the dial on the elevator goes to 12. When on the elevator the doors have the numbers 13 on it, showing that the floor should not exist.

:"See sequence in OEIS for number series and graphs".

How it is done

Skipped

Most commonly, it is skipped altogether. The floor numbered 14 is in fact the thirteenth floor, and 13 is skipped altogether on the elevator console. Any calculations involving the height of a building based on the height of a floor will take this into account.

12A

Sometimes the floor is simply renumbered as "12a" or "12b"; this does not affect the numbers of the higher floors. [cite web
url=http://www.usatoday.com/travel/hotels/2007-03-08-13th-floor-usat_N.htm
title=Some hotels don't skip the 13th floor anymore
last=De Lollis
first=Barbara
publisher=USA Today
date=2007-03-07
accessdate=2008-04-13]

Special designations

Other buildings will often use names for certain floors to avoid giving a floor on the building the number 13 designation. One such example is the Radisson Hotel in Winnipeg, Manitoba, where the 13th floor is called the Pool floor.

Uninhabited

Sometimes, the floor is put to some other use (see conspiracy theories, below).

Letter M

Because the letter M is the 13th letter in the English alphabet, some people may use a letter M as a substitute for the floor numbered 13, such as 12, M, 14, and so forth. In Richmond, Virginia, the Monroe Park Towers has a 13th floor, but it is used for mechanical equipment and is only accessible from the freight elevator or the stairs. The M designation on the elevator buttons of the freight elevator can also be construed as meaning the "Mechanical" level in this particular building, or as a "Mezzanine" level.

Variant

, the predominant language for the country, and most other Chinese languages. A small number of buildings also follow the Western tradition of omitting the thirteenth floor, with the fifteenth floor immediately following the twelfth.

Although the Hanja for four and death are read identically in Korean, buildings in South Korea tend not to omit the fourth floor. However, newer buildings tend to label the fourth floor with the letter F, instead of the number 4.

Conspiracy theory

Some conspiracy theorists have suggested that the thirteenth floor in government buildings is not really missing, but actually contains top-secret governmental departments, or more generally that it is proof of something sinister or clandestine going on fact|date=August 2007. This implication is often carried over, implicitly or explicitly, into popular culture; for example in:
* the films "The Thirteenth Floor" and "Nightmare on the 13th Floor"
* the hidden research and development labs of Network 23 in the television program 'Max Headroom'
* the top-secret research and development division of The Hitchhiker's Guide to the Galaxy in the fifth book of the series, "Mostly Harmless"
* the computer game "Floor 13" by Virgin Interactive
* the sci-fi comedy Red Dwarf where "floor 13" referred to a secret brig which was several decks high.
* the book Company by Max Barry

It is widely believed that Canary Wharf's One Canada Square houses a physical plant room on its level 13 but this is just another example of undeserved notoriety on the part of the 13th floor. One Canada Square's plant areas are in its basements (Levels B3 to M1) and above Level 50 (Level M2). The floor directly above level 12 is level 14.Fact|date=May 2008

References

See also

*Fourth floor, unused mostly in Asian cultures
*Triskaidekaphobia
*13 (number)
*Storey
*Mechanical floor
*Thirteenth floor (disambiguation)