World's tallest structures

There is much debate as to the ranking of the World's tallest structures, chiefly depending on the criteria used for selecting the structures admissible to the list.

In particular, there is debate about whether:

• guy-wire-supported structures can be counted
• only habitable height counts
• roof-top antennass can be counted towards height of inhabitable buildings
• observation galleries on communication towers make them into inhabitable buildings
• structures under construction can be included in the list
• structures rising out of water should have their below-water height included

Table of contents

1 The World's tallest structures (of any sort) 2 The World's tallest structures (not supported by guy-ropes) 3 The World's tallest habitable buildings 4 Historical height records 5 Proposed record-breaking structures 6 Related articles 7 External references

The World's tallest structures (of any sort)

The tallest currently-standing structure is the KVLY-TV mast in North Dakota, at 629m (2,063 feet). It is a transmission antenna, consisting of a bare metal structure supported by guy-wires. There was once a taller such mast, the Warszawa radio mast near Warsaw, Poland at 645m (2,115 feet), but it collapsed in 1991.

The World's tallest structures (not supported by guy-ropes)

The Petronius Platform stands 610m (2,100 feet) tall, making it the tallest freestanding structure in the world. However, as this oil and natural gas platform is partially supported by buoyancy, some critics feel the below-water height should not be accounted for. The CN Tower in Toronto stands 553.33m (1,815 feet) tall, making it the tallest freestanding structure on land.

The World's tallest habitable buildings

The Council on Tall Buildings and Urban Habitat has defined four categories in which the "world's tallest building" can be measured:

1. Height to the structural or architectural top (including spires, but excluding antennas).
2. Height to the highest occupied floor.
3. Height to the top of the roof.
4. Height to the top of antenna.

The height is measured from the sidewalk level of the main entrance.

As of October 17, 2003, Taipei 101 in Taipei, Taiwan leads in the first category with 508m (1,667ft), and in the third category with 448m (1,470ft). The first was formerly held by the Petronas Towers in Kuala Lumpur, Malaysia with 452m (1,483 feet). The second category is held by the Sears Tower in Chicago, with 435m (1,431 feet): when Taipei 101 is occupied in 2004, it will claim this category with an occupied floor at 438 m (1,437 ft). The third category was formerly held by the Sears Tower with 442m (1,445 feet).

The Sears Tower in Chicago also leads in the fourth category with 529m (1736ft), previously held by New York City's World Trade Center until its destruction in 2001; its antenna included, it measured 536m (1,758 feet). The World Trade Center became the world's tallest buildings to be demolished - indeed, its site entered the record books twice on September 11, 2001, in that category, replacing the Singer Building, which once stood a block from the WTC site.

The CN Tower is excluded from these categories because it is not a "habitable building", which is defined as a frame structure made with floors and walls throughout.

Historical height records

Name	Type	TopFloor	Roof	Top	Antenna	Floors	Year	Records
Warszawa radio mast	Guyed radio mast	-	-	-	645m	-	1974-1991	1974-1991: Historical tallest structure
KVLY-TV mast	Guyed radio mast	-	-	-	629m	-	1963-	1991- now: Tallest structure
Petronius Platform	Deepwater oil rig	-	-	610m	-	-	1998-	1998- now: Tallest non-guyed structure
CN Tower	Communications tower	457m	-	-	553m	-	1976-	1976-now: Tallest freestanding land structure 1976-now: Highest number of stair landings (147)
Taipei 101	Office highrise	438m	448m	508m	-	101	2004-	2003- now: Tallest floor 2003- now: Tallest roof 2003- now: Tallest top
Sears Tower	Office highrise	435m	443m	443m	529m	108	1973-	1973-2003: Tallest floor 1973-2003: Tallest roof 1973-1998: Tallest top 2001- now: Tallest antenna 2001- now: Highest # of floors
One World Trade Center	Office highrise	417m	417m	417m	536m	110	1972-2001	1972-1973: Tallest floor 1972-1973: Tallest roof 1972-1973: Tallest top 1972-2001: Tallest antenna 1972-2001: Highest # floors
Petronas Twin Towers	Office highrise	?	?	452m	-	88	1998-	1998-2003: Tallest top
Empire State Building	Office highrise	381m	?	?	449m	102	1931-	1931-1972: Tallest floor 1931-1972: Tallest roof 1931-1972: Tallest top 1931-1972: Tallest antenna 1931-1972: Highest # floors

Proposed record-breaking structures

A Solar tower that has been proposed in Australia would be 1 km (0.62 miles) tall. Engineering feasibility has been demonstrated to the satisfaction of consulting engineers, and construction is a matter of financial viability.

The International Financial Center in Shanghai, China was proposed for completion in 2007, but has been put on hold pending evaluation of soil stability. The current on-going project for the world's tallest is Union Square Phase 7 in Hong Kong, also scheduled for completion in 2007.

Related articles

• Skyscrapers
• List of skyscrapers
• List of World's Tallest Structures
• 50 tallest buildings in the U.S
• World's biggest and largest buildings

External references

• Guinness Book of World Records
• http://www.infoplease.com/ipa/A0001338.html
• http://www.high-rises.co.uk/worlds_tallest.html
• http://www.skyscraperpage.com/index.php
• http://www.skyscrapers.com/
• http://www.xs4all.nl/~hnetten/tallest.html
• http://www.civl.port.ac.uk/comp_prog/weird/tallest.html
• http://www.soyouwanna.com/site/toptens/buildings/buildings.html