There are millions and millions of buildings on our planet. Human beings have been building these sky-kissing buildings for thousands of years. Our common sense tells us that all of these started with a foundation on the ground and grew upward. Surprisingly, there is one building that defies our common sense and began construction from top to bottom. The Plaza de Colón in Madrid, Spain is home to a twin building called “El Enchufe” that translates to “The Plug” as it resembles a giant electrical plug.
The formal name of the plug is “Torres de Colón” or Columbus Towers. Some call it the ugliest building in Madrid for its funny-looking top and a facade made of copper and smoked glass. Whether the locals like it or not, the building constructed in 1976 is considered an icon in the city’s skyline, mostly for its unusual construction from top to bottom.
The Torres de Colón began with two central pillars on a concrete footing and then the topmost floor was raised and hung with steel cables. Each of the next floors was individually constructed and gradually added to the building like beads to a string. The plug-like structure at the top was the last one to be added. The unusual method saves time and cost while eliminating the need for moving workers, materials, and equipment from floor to floor.
The technique is quite unusual and is not widely known, but many other buildings have been constructed this way already. One of them is the Central Bank of Ireland in Dublin and the Standard Bank Centre in Johannesburg, South Africa. Three others in Poland were also built from top to bottom. One of them known as Trzonolinowiec in Wroclaw is often called “hanging man.” The cities of Gdansk and Katowice each hold one of these buildings, and so does the Bulgarian city of Sofia.
Suspending floors from steel cables is not the only way of constructing these ‘top to bottom’ buildings. The industrial city of Magnitogorsk in Russia experimented with a technique where the floors were constructed and then fixed in place with the top floors. Netherlands attempted a variation of this technique called the Jackblock.
According to the American Society of Civil Engineers,
“In the Jackblock construction, the top story of a building is constructed at ground level on a large number of jacks. It is then jacked up an amount equal to its exact height, and another is built underneath it. What is now a two-story block is jacked up another level and the third floor and walls built underneath. These three floors are jacked up, and so it goes until the building has reached its exact height. It is then anchored to the foundations.”
Who cares whether it is built from bottom to top or top to bottom. All that matters is the final structure on the ground. What do you say?
