Skyscraper

A skyscraper is a tall building with many habitable floors. Most modern sources define skyscrapers as being at least 100 metres (328 ft) or 150 metres (492 ft) in height, though there is no universally accepted definition, other than being very tall high-rise buildings. Skyscrapers may host offices, hotels, residential spaces, and retail spaces. Skyscrapers are a common feature of large cities, especially in the Americas, Asia, and Australia, often due to a high demand for space and limited availability of land.

Skyscrapers first appeared in the United States at the end of the 19th century, especially in the cities of Chicago and New York City. One common feature of skyscrapers is having a steel frame that supports curtain walls. Modern skyscrapers often have a tubular structure, and are designed to act like a hollow cylinder to resist wind, seismic, and other lateral loads.

There are over seven thousand skyscrapers over 150 m (492 ft) in height worldwide, most of which were built in the 21st century. The tallest skyscraper in the world is the Burj Khalifa in Dubai, with a height of 828 m (2,717 ft). Skyscrapers are an increasingly global phenomenon, and can be found in at least 70 countries.

Definition

The word "skyscraper" started being used in the late 1800s for very tall buildings made with steel frames. People were amazed by these tall structures popping up in big cities like New York City, Philadelphia, Boston, Chicago, Detroit, and St. Louis.

The first building considered a skyscraper was the Home Insurance Building in Chicago, built in 1885. It had 10 stories and was 42 meters tall. Steel framing allowed architects to build even taller buildings, leading to the supertall skyscrapers we see today around the world. Different groups may have slightly different ideas about what counts as a skyscraper, but they all agree these are very tall, impressive structures.

What is the chief characteristic of the tall office building? It is lofty. It must be tall. The force and power of altitude must be in it, the glory and pride of exaltation must be in it. It must be every inch a proud and soaring thing, rising in sheer exaltation that from bottom to top it is a unit without a single dissenting line.

— Louis Sullivan's The Tall Office Building Artistically Considered (1896)

History

Precursors

The tallest structure in ancient times was the 146 m (479 ft) Great Pyramid of Giza in ancient Egypt, built in the 26th century BC. It stayed the tallest for thousands of years until the 160 m (520 ft) Lincoln Cathedral in England exceeded it in 1311. However, Lincoln Cathedral’s central spire later collapsed. The 555-foot (169 m) Washington Monument in the United States became the tallest in 1884, followed by the Eiffel Tower in France in 1889. None of these were truly habitable buildings like modern skyscrapers.

In ancient Rome, buildings called insulae reached up to ten stories high. In the Middle Ages, cities like Bologna had many tall towers, with the Asinelli Tower standing at 97.2 m (319 ft). The city of Shibam in Yemen is famous for its over 500 mudbrick tower houses, each 5 to 11 stories tall, built for protection.

Early skyscrapers

The safety elevator, invented by Elisha Otis in 1857, made tall buildings practical. The Home Insurance Building in Chicago, built from 1884 to 1885, was an early example using a steel frame instead of thick walls. This design became known as the “Chicago skeleton” and influenced future skyscrapers.

Skyscrapers began appearing in land-limited cities like New York and Chicago in the late 1800s. Height limits and fire safety rules later developed. In Europe, tall buildings were restricted to protect views of important landmarks like St Paul’s Cathedral in London.

Modern skyscrapers

Modern skyscrapers are built with steel or reinforced concrete frameworks and glass or stone curtain walls. They include mechanical systems like water pumps and elevators.

After World War II, skyscraper construction grew in many parts of the world, including Europe, Asia, Latin America, Africa, the Middle East, South Asia, and Oceania. Architects like Ludwig Mies van der Rohe helped shape modern skyscraper design with glass facades.

In the 1960s, innovations by engineers like Fazlur Rahman Khan allowed for new structural designs, such as the “tube” system, which made taller, more efficient buildings possible. Today’s skyscrapers focus on sustainability, using materials and designs that reduce environmental impact.

New York City and Chicago competed to build the tallest buildings in the 1920s and 1930s, with the Chrysler Building and Empire State Building claiming the title. The World Trade Center became the tallest in 1972 before being surpassed by the Willis Tower in Chicago. The Petronas Twin Towers in Malaysia later took the record.

Design and construction

The design and construction of skyscrapers focus on creating safe, tall buildings that can support their own weight, resist wind and earthquakes, and keep people comfortable inside. These buildings need strong frameworks to hold up all the floors and must have good ways to move people up and down, like elevators.

Skyscrapers often use a steel framework that allows walls to be made mostly of windows. This style began during the industrial age when materials like steel and concrete became easier to work with. Special designs, like tubular shapes, help skyscrapers reach even greater heights while using less material.

Elevators are key to skyscrapers, making it easy for people to travel between floors. Modern buildings sometimes use special elevator setups, like sky lobbies or double-deck elevators, to save space and carry more people. These designs help balance the need for height with the space needed for elevators.

Economic rationale

Skyscrapers are most often built in city centres where land is very valuable. When land is expensive, it makes more sense to build tall structures upward rather than spreading out, saving money while creating lots of space inside. This is why you see skyscrapers in big cities rather than smaller towns.

Because of the high cost of space in city centers, most people who rent rooms in skyscrapers are offices, shops, and hotels. Building very tall skyscrapers can also have some problems, like needing many elevators to move people quickly. To solve this, some skyscrapers have special floors called sky lobbies where people can switch to slower elevators to reach their floor.

Environmental impact

Further information: Bird-skyscraper collisions

Building a skyscraper needs lots of materials like steel, concrete, and glass. This takes a lot of energy and resources. Making a skyscraper also needs strong foundations and lots of electricity for things like pumping water, using elevators, and lighting rooms far from windows.

Skyscrapers can use energy wisely. They can use natural light, special designs to save energy, and even get power from the sun. Some famous skyscrapers, like the Empire State Building and The Gherkin in London, show how tall buildings can help the environment.

In the lower parts of a skyscraper, more space is needed for strong structures and services like elevators and pipes. As buildings get taller, they need more energy for things like elevators and cooling. But with smart planning, skyscrapers can use natural air flow and cooler temperatures at higher levels to save energy.

History of the tallest skyscrapers

Main articles: History of the tallest buildings in the world and List of tallest buildings

In the early 1900s, New York City became a key place for building very tall structures. With new technology, cities like New York and Chicago competed to build the tallest buildings. Many famous skyscrapers were built there, changing how we think about architecture.

Some important early skyscrapers include the E. V. Haughwout Building, which had the first passenger elevator, and the Home Insurance Building in Chicago, the first with a steel skeleton. The Singer Building and the Metropolitan Life Insurance Company Tower were also record-breakers in their time. Later, the Chrysler Building and the famous Empire State Building became icons of New York City.

In the 1970s, the World Trade Center towers stood as the tallest, until they were surpassed by the Sears Tower, now called the Willis Tower. Today, the tallest building is the Burj Khalifa in Dubai, which shows how skyscraper designs have evolved to reflect different cultures around the world.

Future developments

See also: List of visionary tall buildings and structures and List of future tallest buildings

People have proposed building very tall structures, such as the Burj Mubarak Al Kabir in Kuwait and Azerbaijan Tower in Baku. One building now being built, planned to be over one kilometre tall, is the Jeddah Tower.

Wooden skyscrapers

Main article: List of tallest wooden buildings

Architects have created designs for tall wooden buildings. In 2015, a 14-story housing project in Bergen, Norway called 'Treet' or 'The Tree' became the tallest wooden apartment building in the world. In 2016, an 18-story wooden building at the University of British Columbia in Canada named Brock Commons took that record.

There are plans for even taller wooden buildings. One idea is a 40-story building in Stockholm, Sweden called 'Trätoppen'. Another plan is for a 70-story building in Tokyo called the W350 Project, to be built by a company to celebrate its 350th anniversary in 2041. There is also a proposal for an 80-story wooden building in Chicago, Illinois called the River Beech Tower.

Wooden skyscrapers can be much lighter than concrete buildings and help reduce the amount of carbon in the air. They can be built using a special type of wood called cross-laminated timber (CLT), which makes the wood stronger and easier to put together.