high-rise

A high-rise residential apartment building in Hong Kong.

A high-rise is a tall building or structure. Normally, the function of the building is added, for example high-rise apartment building or high-rise offices. Compare: low-rise

High-rise buildings became possible with the invention of the elevator (lift) and cheaper, more abundant building materials. Buildings between 75 feet (23 m) and 491 feet (150 m) high are, by some standards, considered high-rises. Buildings taller than 492 feet (150 m) are classified as skyscrapers. The average height of a level is around 13 feet (4 m) high, thus a 79 foot (24 m) tall building would comprise 6 floors.

The materials used for the structural system of high-rise buildings are reinforced concrete and steel. Most American style skyscrapers have a steel frame, while residential tower blocks are usually constructed out of concrete.

Although there is no precise definition that is universally accepted, various bodies have tried to define what 'high-rise' means:

• The International Conference on Fire Safety in High-Rise Buildings defined a high-rise as "any structure where the height can have a serious impact on evacuation"
• The New Shorter Oxford English Dictionary defines a high-rise as "a building having many stories".
• Massachusetts General Laws define a high-rise as being higher than 70 feet (21 m).
• According to the building code of Hyderabad, India, a high-rise building is one with four floors or more, or one 15 meters or more in height.^[1]
• Most building engineers, inspectors, architects and similar professions define a high-rise as a building that is at least 75 feet (23 m) tall.
• Emporis Standards defines a high-rise as "A multi-story structure between 35-100 meters tall, or a building of unknown height from 12-39 floors."^[2]

High-rise structures pose particular design challenges for structural and geotechnical engineers, particularly if situated in a seismically active region or if the underlying soils have geotechnical risk factors such as high compressibility or bay mud. They also pose serious challenges to firefighters during emergencies in high-rise structures. New and old building design, building systems like the building standpipe system, HVAC systems (Heating, Ventilation and Air conditioning), fire sprinkler system and other things like stairwell and elevator evacuations pose significant problems.

History

High-rise apartment buildings had already appeared in antiquity: the insulae in ancient Rome and several other cities in the Roman Empire, some of which might have reached up to 10 or more stories,^[3] one reportedly having 200 stairs.^[4] Because of the destruction caused by poorly-built high-rise insulae collapsing,^[5] several Roman emperors, beginning with Augustus (r. 30 BC - 14 AD), set limits of 20-25 metres for multi-story buildings, but met with limited success,^[6][7] as these limits were often ignored despite the likelihood of taller insulae collapsing.^[8] The lower floors were typically occupied by either shops or wealthy families, while the upper stories were rented out to the lower classes.^[9] Surviving Oxyrhynchus Papyri indicate that seven-storey buildings even existed in provincial towns, such as in 3rd century AD Hermopolis in Roman Egypt.^[10]

In Arab Egypt, the initial capital city was Fustat. It housed many high-rise residential buildings, some seven stories tall that could reportedly accommodate hundreds of people. Al-Muqaddasi in the 10th century described them as resembling minarets, while Nasir Khusraw in the early 11th century described some of them rising up to 14 stories, with roof gardens on the top storey complete with ox-drawn water wheels for irrigating them.^[11][12][13] By the 16th century, Cairo also had high-rise apartment buildings where the two lower floors were for commercial and storage purposes and the multiple stories above them were rented out to tenants.^[14]

The skyline of many important medieval cities was dominated by large numbers of high-rising urban towers which fulfilled defensive, but also representative purposes. The residential Towers of Bologna numbered between 80 to 100 at a time, the largest of which still rise to 97.2 m. In Florence, a law of 1251 decreed that all urban buildings should be reduced to a height of less than 26 m, the regulation immediately put into effect.^[15] Even medium-sized towns such as San Gimignano are known to have featured 72 towers up to 51 m height.^[15]

The 16th century Yemeni city of Shibam is made up of over 500 tower houses,^[16] each one rising 5 to 11 storeys high,^[17] with each floor having one or two apartments.^[18] The city has the tallest mud buildings in the world, with some of them over 30 meters (100 feet) high.^[19]

Currently, the tallest high-rise apartment building in the world is Chicago's John Hancock Center, constructed under the supervision of Skidmore, Owings & Merrill and completed in 1969. The building has 100 stories and stands at 344 meters tall.^[20]

References

See also

Wikimedia Commons has media related to: High-rises

• Skyscraper
• Tower block
• Earthquake engineering
• Wind engineering