Tall buildings are becoming ever more prevalent in our cities, as demand for space in densely
populated urban areas increases and as engineering capabilities develop.
The terms “tall”, “high-rise” and “skyscraper” are often used interchangeably
when describing structures that are notable for their height - but there is in fact a
distinction between buildings which are tall and true “skyscrapers”.
Here we explain the difference.
There is no clear definition on what constitutes a “tall building” and it is to some extent subjective.
A 10-storey structure that is the tallest building in regional town or low rise city
for example, would easily become lost if it were placed in Chicago or Hong Kong.
Many groups class 50 metres (or 165 feet) as the threshold for a tall building, but
this is by no means a widely accepted rule.
In reality the term “tall building” is commonly used in our everyday language to
describe any structure that rises to a significant or noticeable height.
To qualify as a true “skyscraper”, a structure must be self-supporting and not require tension
cables or supports in order to remain standing.
In addition, habitable floor space must occupy at least 50% of the structure’s total height.
As a result, communication and observation towers - such as Tokyo’s Skytree
are not considered to be skyscrapers.
Finally “skyscrapers” must rise to a minimum height of 150 metres (or 492 feet).
While this used to be an exclusive club, there are now countless buildings around the world
that fall into this definition, and as engineering and construction techniques have continued
to develop, we’ve pushed the limits of building at height.
To distinguish these remarkable structures from other skyscrapers,
the Council on Tall Buildings and Urban Habitat have created two additional categories.
Supertall buildings rise to more than 300 metres (or 984 feet) in height.
Such towers used to be an exception, with only 22 schemes reaching this height in the 20th Century.
However, since 2000, the number of supertall buildings over 300 metres either completed or under
construction has risen to almost 300 at the time of filming.
Prominent examples include New York City’s 432 Park Avenue and 53 West 53rd Street…
...along with the KK100 Tower in Shenzhen, China.
The proliferation of schemes meeting the criteria for “supertall” has led to the creation
of the final and truly exclusive top tier category.
With just three towers worldwide at the time of filming, structures that reach the dizzying
height of more than 600 metres (or 1,969 feet) move into the class of “megatall”.
This rare classification is currently only applied to the 601 metre Abraj al Bait Tower in Saudi Arabia
which with a construction cost of over USD $15BN is the world’s most expensive skyscraper
...the 632 metre Shanghai Tower in China…
...and the world’s current tallest building, the 828 metre Burj Khalifa in the United Arab Emirates.
Further structures are of course set to enter this bracket in the years ahead - with the
most notable development at present being the Jeddah Tower in Saudi Arabia
a megatall structure
that is on course to break the 1 kilometre mark and become the world’s tallest building.
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