high rise

A tower block, high-rise, apartment tower, residential tower, apartment block, block of flats, or office tower is a tall building, as opposed to a low-rise building and is defined differently in terms of height depending on the jurisdiction. It is used as a residential, office building, or other functions including hotel, retail, or with multiple purposes combined. Residential high-rise buildings are also known in some varieties of English, such as British English, as tower blocks and may be referred to as MDUs, standing for multi-dwelling units. A very tall high-rise building is referred to as a skyscraper.

High-rise buildings became possible to construct with the invention of the elevator (lift) and with less expensive, more abundant building materials. The materials used for the structural system of high-rise buildings are reinforced concrete and steel. Most North American-style skyscrapers have a steel frame, while residential blocks are usually constructed of concrete. There is no clear difference between a tower block and a skyscraper, although a building with forty or more stories and taller than is generally considered a skyscraper.

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. Studies are often required to ensure that pedestrian wind comfort and wind danger concerns are addressed. In order to allow less wind exposure, to transmit more daylight to the ground and to appear more slender, many high-rises have a design with setbacks.

Apartment buildings have technical and economic advantages in areas of high population density, and have become a distinctive feature of housing accommodation in virtually all densely populated urban areas around the world. In contrast with low-rise and single-family houses, apartment blocks accommodate more inhabitants per unit of area of land and decrease the cost of municipal infrastructure.

Definition

Various bodies have defined "high-rise":

*Emporis defines a high-rise as "A multi-story structure between tall, or a building of unknown height from 12–39 floors."
*According to the building code of Hyderabad, a high-rise building is one with four floors or more, or or more in height.
*The ''New Shorter Oxford English Dictionary'' defines a high-rise as "a building having many storeys".
*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"
*In the U.S., the National Fire Protection Association defines a high-rise as being higher than , or about seven stories.
*Most building engineers, inspectors, architects and similar professionals define a high-rise as a building that is at least 75 feet tall.

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 ten or more stories, one reportedly having 200 stairs. Because of the destruction caused by poorly built high-rise ''insulae'' collapsing, several Roman emperors, beginning with Augustus (r. 30 BC – 14 AD), set limits of for multi-story buildings, but met with limited success, as these limits were often ignored despite the likelihood of taller ''insulae'' collapsing. The lower floors were typically occupied by either shops or wealthy families, while the upper stories were rented out to the lower classes. Surviving Oxyrhynchus Papyri indicate that seven-story buildings even existed in provincial towns, such as in third century AD Hermopolis in Roman Egypt.Papyrus Oxyrhynchus 2719, in: Katja Lembke, Cäcilia Fluck, Günter Vittmann: ''Ägyptens späte Blüte. Die Römer am Nil'', Mainz 2004, , p. 29

In Arab Egypt, the initial capital city of Fustat 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 story complete with ox-drawn water wheels for irrigating them. 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.

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 and 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.Werner Müller: "dtv-Atlas Baukunst I. Allgemeiner Teil: Baugeschichte von Mesopotamien bis Byzanz", 14th ed., 2005, , p. 345 Even medium-sized towns such as San Gimignano are known to have featured 72 towers up to 51 m in height.

The Hakka people in southern China have adopted communal living structures designed to be easily defensible in the forms of Weilongwu (围龙屋) and Tulou (土楼), the latter are large, enclosed and fortified earth building, between three and five stories high and housing up to 80 families. The oldest still standing tulou dates back from the 14th century.

High rises were built in the Yemeni city of Shibam in the 16th century. The houses of Shibam are all made out of mud bricks, but about five hundred of them are tower houses, which rise five to sixteen stories high, with each floor having one or two apartments.Old Walled City of Shibam
UNESCO World Heritage Centre This technique of building was implemented to protect residents from Bedouin attacks. While Shibam has existed for around two thousand years, most of the city's houses date from the 16th century. The city has the tallest mud buildings in the world, some more than 30 meters (100 feet) high. Shibam has been called "one of the oldest and best examples of urban planning based on the principle of vertical construction" or "Manhattan of the desert".

The engineer's definition of high-rise buildings comes from the development of fire trucks in the late 19th century. Magirus had shown the first cogwheel sliding ladder in 1864. The first turntable ladder drawn by horses was developed in 1892 which had a length of 25 meters. The extension ladder was motorized by Magirus in 1904. The definition of a maximum of 22 meters for the highest floor was common in the building regulations at the time and it is still so today in Germany. The common height for turntable ladders did later go to 32 meters (100 feet), so that 30 meter is a common limit in some building regulations today, for example in Switzerland. Any building that exceeds the height of the usual turntable ladders in a city must install additional fire safety equipment, so that these high-rise buildings have a different section in the building regulations in the world.

Currently, the tallest high-rise apartment building in the world is the Central Park Tower on Billionaires' Row in Midtown Manhattan, towering at .

Modern development

The residential tower block with its typical concrete construction are a familiar feature of Modernist architecture. Influential examples include Le Corbusier's "housing unit" his ''Unité d'Habitation'', repeated in various European cities starting with his ''Cité radieuse'' in Marseille (1947–52), constructed of ''béton brut'', rough-cast concrete, as steel for framework was unavailable in post-war France. Residential tower blocks became standard in housing urban populations displaced by slum clearances and "urban renewal".
High-rise projects after World War II typically rejected the classical designs of the early skyscrapers, instead embracing the uniform international style; many older skyscrapers were redesigned to suit contemporary tastes or even got demolished - such as New York's Singer Building, once the world's tallest skyscraper. However, with the movements of Postmodernism, New Urbanism, and New Classical Architecture, that established since the 1980s, a more classical approach came back to global skyscraper design, that is popular today.

Other contemporary styles and movements in highrise design include organic, sustainable, neo-futurist, structuralist, high-tech, deconstructivist, blob, digital, streamline, novelty, critical regionalist, vernacular, Neo Art Deco, and neohistorist, also known as revivalist.

Asia

Residential tower complexes are common in Asian countries such as China, India, Bangladesh, Indonesia, Taiwan, Singapore, Japan, Pakistan, Iran and South Korea, as urban densities are very high. In Singapore and urban Hong Kong, land prices are so high that a large portion of the population lives in high-rise apartments. In fact, over 60% of Hong Kong residents live in apartments, many of them condominiums. Of them in 2020, 2,112,138 were identified residents of public housing, which is 28% of the total population.

Sarah Williams Goldhagen (2012) celebrated the work of innovative architecture firms such as WOHA (based in Singapore), Mass Studies (based in Seoul), Amateur Architecture Studio (based in Hangzhou, China), and the New York City-based Steven Holl in the transformation of residential towers into "vertical communities" or "vertical cities in the sky" providing aesthetic, unusually designed silhouettes on the skyline, comfortable private spaces and attractive public spaces. None of these "functional, handsome, and humane high-rise residential buildings" are affordable housing.

China

The 2012 Pritzker Prize was awarded to Chinese architect Wang Shu. Among his winning designs is the Vertical Courtyard Apartments, six 26-story towers by his architectural firm Amateur Architecture Studio built in Hangzhou. "These towers were designed to house two-story apartments, in which every inhabitant would enjoy “the illusion of living on the second floor”, accomplished by folding concrete floor planes (like “bamboo mats,” claims the firm), so that every third story opens into a private courtyard. In the larger towers, the two-story units are stacked slightly askew, adding to the visual interest of the variegated façades (Goldhagen 2012)."

Japan

Housing in Japan includes various traits coming from different eras. The word '' danchi'' now either means an employer-provided housing or has a meaning similar to " projects". For modern hi-rises, there are two borrowed words to make a distinction:
* "''Apaato''" (アパート）is used to describe a rather small apartment, initially made to be rented
* a large, modern apartment would usually be referred to as a "''Mansion''" (マンション). The "mansion" nickname is used for both residential towers and its individual condominium apartments (for being spacy enough to compare to detached houses).

South Korea

In South Korea, the tower blocks are called Apartment Complex (). The first residential towers began to be built after the Korean War. The South Korean government needed to build many apartment complexes in the cities to be able to accommodate the citizens. In the 60 years since, as the population increased considerably, tower blocks have become more common. This time, however, the new tower blocks integrated shopping malls, parking systems, and other convenient facilities.

Samsung Tower Palace in Seoul, South Korea, is the tallest apartment complex in Asia.

In Seoul, approximately 80 percent of its residents live in apartment complexes which comprise 98 percent of recent residential construction. Seoul proper is noted for its population density, eight times greater than Rome, though less than Manhattan and Paris. Its metropolitan area is the densest in the OECD.

Europe

Central and Eastern Europe

Although some Central and Eastern European countries during the interwar period, such as the Second Polish Republic, already started building housing estates that were considered to be of a very high standard for their time, many of these structures perished during the Second World War.

In the Eastern Bloc, tower blocks were constructed in great numbers to produce plenty of cheap accommodation for the growing postwar populations of the USSR and its satellite states. This took place mostly in the 1950s, 1960s and 1970s of the 20th century, though in the People's Republic of Poland this process started even earlier due to the severe damages that Polish cities sustained during World War II. Throughout the former Eastern Bloc countries, tower blocks built during the Soviet years make up much of the current housing estates and most of them were built in the specific socialist realist style of architecture that was dominant in the territories east of the Iron Curtain: blocky buildings of that era are colloquially known as Khrushchyovka. In Romania, the mass construction of standardized housing blocks began in the 1950s and 1960s with the outskirts of the cities, some of which were made up of slums. Construction continued in the 1970s and 1980s, under the systematization programme of Nicolae Ceaușescu, which consisted largely of the demolition and reconstruction of existing villages, towns, and cities, in whole or in part, in order to build blocks of flats (''blocuri''), as a result of increasing urbanization following an accelerated industrialization process. In Czechoslovakia (now the Czech Republic and Slovakia), panelák building under communism resulted from two main factors: the postwar housing shortage and the ideology of communist Czechoslovak leaders.

In Eastern European countries, opinions about these buildings vary greatly, with some deeming them as eyesores on their city's landscape while others glorify them as relics of a bygone age. Since the dissolution of the Soviet Union, and especially in the late 1990s and early 2000s, many of the former Eastern Bloc countries have begun construction of new, more expensive and modern housing. The Śródmieście borough of Warsaw, the capital of Poland, has seen the development of an array of skyscrapers. Russia is also currently undergoing a dramatic buildout, growing a commercially shaped skyline. Moreover, the ongoing changes made to postwar housing estates since the 2000s in former communist countries vary - ranging from simply applying a new coat of paint to the previously grey exterior to thorough modernization of entire buildings.

In the European Union, among former communist states, a majority of the population lives in flats in Latvia (65.1%), Estonia (63.8%), Lithuania (58.4%), Czech Republic (52.8%), and Slovakia (50.3%) (, data from Eurostat). However, not all flat dwellers in Eastern Europe live in communist era blocks of flats; many live in buildings constructed after the fall of communism, and some in buildings surviving from the era before communism.

Western Europe

In Western Europe, there are fewer high-rise buildings because of the historic city centres. In the 1960s, developers began demolishing older buildings to replace them with modern high-rise buildings.

In Brussels there are numerous modern high-rise buildings in the Northern Quarter business district. The government of Belgium wants to recreate Washington, D.C. on a small scale.

=Great Britain

=

Tower blocks were first built in the United Kingdom after the Second World War, and were seen as a cheap way to replace 19th-century urban slums and war-damaged buildings. They were originally seen as desirable, but quickly fell out of favour as tower blocks attracted rising crime and social disorder, particularly after the collapse of Ronan Point in 1968.

Although Tower blocks are controversial and numerous examples have been demolished, many still remain in large cities. Due to lack of proper regulation, some tower blocks present a significant fire risk and even though there have been efforts to make them more safe, modern safety precautions can be prohibitively expensive to retrofit. The Grenfell Tower fire in 2017 was partly caused by council ignorance, as a local action group complained to the council about the fire hazards of the tower several years before the incident, yet remedial work had not been carried out. This fire further made tower blocks less desirable to British residents.

There are old high-rise buildings built in the 1960s and 1970s in areas of London such as Tower Hamlets, Newham, Hackney, and virtually any area in London with council housing. Some new high-rises are being built in areas such as Central London, Southwark, and Nine Elms. In East London, some old high-rises are being gentrified and new high-rises that previously didn't exist are also being built in areas like Stratford, London and Canary Wharf.

=Ireland

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;Republic of Ireland
The majority of residential high rise buildings in the Republic of Ireland were concentrated in the suburb of Ballymun, Dublin. The Ballymun Flats were built between 1966 and 1969: seven 15-story towers, nineteen 8-story blocks and ten 4-story blocks. These were the "seven towers" referred to in the U2 song "Running to Stand Still". They have since been demolished. Inner Dublin flat complexes, typically of 4-5 storeys include Sheriff Street (demolished), Fatima Mansions (demolished and redeveloped), St Joseph's Gardens (demolished; replaced by Killarney Court flat complex), St Teresa's Gardens, Dolphin House, Liberty House, St Michael's Estate (8 storeys) and O'Devaney Gardens and a lot more mainly throughout the north and south inner city of Dublin. Suburban flat complexes were built exclusively on the northside of the city in Ballymun, Coolock and Kilbarrack. These flats were badly affected by a heroin epidemic that hit working-class areas of Dublin in the 1980s and early 90s.

Residential tower blocks were previously uncommon outside of Dublin, but during the era of the Celtic Tiger the largest cities such as Dublin, Cork, Limerick and Galway witnessed new large apartment building, although their heights have generally been restricted. Some large towns such as Navan, Drogheda, Dundalk and Mullingar have also witnessed the construction of many modern apartment blocks.

;Northern Ireland
Tower blocks in Northern Ireland were never built to the frequency as in cities on the island of Great Britain, but taller high rises are generally more common than in the Republic of Ireland. Most tower blocks and flat complexes are found in Belfast although many of these have been demolished since the 1990s and replaced with traditional public housing units. The mid-rise Divis flats complex in west Belfast was built in between 1968 and 1972. It was demolished in the early 1990s as the residents demanded new houses due to mounting problems with the flats. Divis Tower, built separately in 1966, still stands, however; and in 2007 work began to convert the former British Army base at the top two floors into new dwellings. Divis Tower was for several decades Ireland's tallest residential building, having since being surpassed by the privately owned Obel Tower in the city centre. In the north of the city, the iconic seven-tower complex in the New Lodge remains, although so too the problems that residents face, such as poor piping and limited sanitation. Farther north, the four tower blocks in Rathcoole dominate the local skyline, while in south Belfast, the tower blocks in Seymour Hill, Belvoir & Finaghy