the scale and ambition of skyscrapers leads many of us to view them as permanent fixtures on a city skylines but for all their size and presence these huge structures are in fact just as replaceable as anything else we built so what do you do with buildings this bake
when they reach the end of their lives how do you demolish them in the middle of such heavily developed and densely populated areas to date only a handful of towers taller than 150 meters have ever been intentionally destroyed the process is highly complex specialists and fraught with challenges
in a world that is constructing more tall buildings than ever before and with several structures now slated for demolition to make way for even larger towers this is how the disposed of a skyscraper skyscrapers are a highly effective way of creating space in dense city centers but with
life spans ranging from fifty to a hundred years many no longer provide the right type of space needed in a modern metropolis now an increasing number of tall buildings around the world are being earmarked for demolition clearing the way for even larger developments in New York City the
216 meter 270 Park Avenue recently became the tallest skyscraper ever to be intentionally demolished making way for JPMorgan Chase's new 70-story structure when we think about the demolition of a building many of us imagine wrecking balls and dramatic implosions but while these methods may be the quickest way
to destroy large structures like stadiums or casinos their use within built-up heavily populated areas is challenging and the effects of noise dust citizen safety and proximity to other built assets prohibits their use rather than coming down in a matter of seconds the removal of a skyscraper is in
fact a carefully planned process that is carried out piece by piece much like the construction of the building but in Reverse it's perhaps easier to think of the process as deconstruction rather than demolition [Music] while skyscraper disposal can take a few different forms the primary method sees contractors
and engineers start from the top of a structure and work their way down once the relevant demolition plans and permits are approved contractors must first contain and remove any harmful materials or substances such as asbestos to avoid contaminating the surrounding area with internal stripout works underway the building
becomes enclosed in scaffolding and netting to minimize the impact of noise dust and debris on the public and neighboring properties while this can take the form of a complete enclosure like that which went up around Sydney's 188 meter EMP tower during its partial demolition in 2019 the sheer
scale of 270 Park Avenue sees the disposal process broken up into four phases levels 16:29 and 41 of the structure have been stripped out and modified into bracing floors supporting the scaffolding for each section of the tower above as each section is fully enclosed internal fixtures services and
eventually the building's windows are removed leaving only the concrete and steel superstructure remaining this process is repeated for each section of the tower the method of moving waste material from the top of the building down to street level varies between disposal projects but contractors tend to use chutes
and wastes for non structural waste minimizing the time that cranes are needed on-site with windows and cladding removed and the tower stripped to its core superstructure small excavators and handheld tools are used to break up the concrete floor slabs and steel framing this process is steadily repeated level
by level until the skyscraper is no more though there are alternatives to this methods such as this creative demolition in Japan where all work is contained within a hydraulic framework the principles remain much the same while tearing down an entire skyscraper could be seen as wasteful it's important
to note that landfill costs account for a large proportion of a demolition contracts as such every effort is made to reduce the amount of waste material that is sent to landfill by reusing and recycling waste as far as possible to date 270 Park Avenue has reportedly diverted over
90% of its waste away from landfill putting it well ahead of leads highest standards set for demolition projects the cost and effort required to fully dispose of a skyscraper makes it a significant undertaking and the process is seen as a last resort amongst developers though more skyscrapers are
set to be demolished as urban populations expand building adaptation is becoming an increasingly attractive alternative to demolition this process sees skyscrapers significantly altered for new uses while retaining the bulk of their super structures New York City's Woolworth Building had its upper floors converted to luxury residential apartments when
the towers structure prevented it from offering the open-plan offices that large companies required while in Sydney the redundant EMP tower will retain over 60% of its original structure as it transforms into key quarter Tower a 216 metre sustainable skyscraper if you enjoyed this video and would like to
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