Why do We Build Taller Buildings
May 05, 2017
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traffic
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urban geography
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urban sprawl
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water
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why build higher
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why we build
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For years in the western world.
It was thought to be blasphemous to build higher than the a church spire.
The stories of the old testament warned against reaching too close to the heavens.
The builders of the tower of Babel declared: “Come, let us build us a city and a tower with its top in the heavens. And let us make a name for ourselves, lest we be scattered upon the face of the whole earth”
But god punished them for building a monument to humanity and not to God by confusing their language so they could no longer work together.
This story is used as the source of our world’s languages for the religious and some still use it as an argument against our modern world, but it has interesting undertones for the
development of our cities.
For centuries the church spire remained as the focal point of most western cities.
The Trinity Church was the largest building in New York until 1890 when the New York World Building was completed.
This marked an end to the Cathedral dominated skylines of many cities across the world.
Those church spires served as a symbol of piety, but The New York World Building’s height allowed Joseph Pulitzer to expand his growing business without having to find a large swath of land on the outskirts of the city.
Growing taller served a practical purpose and it still does in many cases.
It’s that demand for space that truly drives up the average height of buildings in cities.
Cities like Hong Kong do not have any supertall buildings, but the average height of buildings in Hong Kong is among the highest in the world and that is largely driven by the lack of space available.
Hong Kong is confined by the sea on one side and the Chinese border on the other while having a very mountainous landscape.
There isn’t a huge amount of land to build on.
This forced buildings to grow taller to accommodate the city's population.
When Hong Kong needed to expand their International Airport there was little space available.
Instead they decided to level two islands outside the city to create a new artificial Island, where the new airport is now located.
This project added 1% to the total surface area of Hong Kong.
When space is limited humans are forced to get inventive to cope, but in many cities across the world space is not an issue and these cities usually decide to expand outwards.
This is called urban sprawl and it’s been a topic of debate lately, with calls to stop this decentralisation of cities.
Urban sprawl requires little micro-management of resources, you simply continue to expand current utilities and roads and approve buildings on cheaper undeveloped land.
It’s an easy solution to a growing population, but it creates many problems of it’s own and is completely unsustainable as populations grow.
You cannot simply keep expanding the city and allowing those problems to escalate.
It has huge environmental and social impacts.
One of the most obvious, which my friend Wendover Productions spoke about in his last post, was an increasing commute time.
With an increasing city diameter the distances we have to cover to reach the city centre increases and it is incredibly difficult to serve all of these far flung suburban neighbourhoods with adequate public transport.
This results in a city dependant on the car, our least efficient form of transport.
This not only has a social impact, as long commute times are one of highest and most controllable factors that affect our happiness, but The average American spends 17,600 minutes
behind the wheel a year, much of that is spent in gridlock traffic, that’s equivalent to spending almost an extra 37 days at your traditional 8 hour 9 to 5 job, but it also has a direct
impact on pollution and air quality in the city too.
That’s 17,600 minutes of a car polluting the environment.
Reducing a city's dependence on cars reduces our carbon footprint on this world.
Urban sprawl affects our environment in other ways too.
Spreading our cities creates water distribution problems.
Here in Ireland it is thought that up to 50% of the treated water is lost through pipe leakage and that problem is not unique to Ireland.
In 2010 it was reported that 3.3 billion litres of water was being wasted in the England and Wales through pipe leakage.
Reducing the sprawl reduces the length of pipes needed and thus reduces the chances of leakages and the problem can be attenuated further by creating buildings with self sustaining
water supplies.
This is becoming a growing trend and consideration among engineers.
LEED or Leadership in Energy and Environmental Design is one of the most popular green building certifications used world wide.
It rates how resource efficient buildings are in their construction, energy use and water use.
The Taipei 101 was awarded LEED’s highest certification with a platinum certificate.
It achieved this with it’s own dedicated water management systems and low-flow water fixtures.
This design ideology helped the Taipei 101 to decrease it’s potable water consumption by at least 30% compared to the average building consumption, saving about 28 million liters
of potable water annually.
When you also consider that in America landscape irrigation is estimated to account for nearly one third of all residential water use, totaling nearly 9 billion gallons of water per day.
It would be vastly more sustainable for a world where water is in ever increasing demand to create cities where we have a larger percentage of LEED certified high rise residential buildings.
This goes beyond just environmental impacts, there are a number of socio-economic motivations to creating more high rise buildings too.
I pointed out that the urban sprawl results in longer commutes and the roads and public transportation needed to facilitate those commutes are not free.
They need to be maintained and built with your tax money and while building up is more costly, that cost and risk is usually incurred on private contractors and the costs of building up starts to decline once you reach a certain height.
To build a skyscraper there are a number fixed costs, but many of these costs do not increase with the height of the building.
Fixed costs like the cost of land, legal fees and design costs can be offset by building higher.
If the building is built on a 100 square metre plot of land and the building has 40 stories, each floor only takes up 2.5 square metres of land.
That has obvious economic advantages, especially when you consider design and material costs only start to go up when you reach around the 40th floor and that critical height is
likely to go up as technology improves.
Buildings like the Burj Khalifa may be just exuberant displays of wealth, but they do serve as technology demonstrators.
For 25 years the tallest building in the world was the Sears Tower, now known as the Willis Tower.
It uses a bundled tube structure, which maximises the amount floor space, but if we scale this building to the size of the Burj Khalifa.
It’s floor space would be dominated by structural elements and the interior would have no natural light.
As mentioned in my last post, the buttressed core of the Burj Khalifa provides the structural integrity needed to reach these heights, while maximizing both the window access and usable space.
This is vital knowledge and experience to have to allow building heights to keep growing while keeping costs down.
So you may be thinking why aren’t there more high rises buildings.
If there are all these benefits there must be reasons that we aren’t building more of them.
So they primary reason we aren’t building higher is because of city planning and regulatory problems.
Take New York’s growth in the early 20th century as an example, building heights were growing and many were unhappy with it.
At the time 5th Avenue was filled with stately mansions, homes to the wealthy families of New York like the Carnegies and Rockefellers.
They worried that unless building heights were restricted, 5th avenue would turn into a dark cannon, overshadowed by these towering behemoths.
These worries led to 1916 zoning resolution which allowed buildings to grow in height, but restricted their width as they grew.
This is one of the primary reasons so many buildings in New York built during that era taper towards their top.
It was a measure to prevent buildings from blocking the sunlight below, but the regulation had loop holes and architects quickly exploited them.
Between 1916 and 1960 the city’s zoning code was amended 2500 times.
The 1961 Zoning Resolution brought in strict rules and introduced a new floor to area ratio rule that restricted buildings heights according to the district they were.
The floor to area ratio set how much floor space could be built on a plot of land.
A floor to area ratio of 2 means you can build a 2 story building on your full plot or a 4 story building on half your plot.
R1, R2 and R3 districts are low density zones like Staten Island and the Jamaica Estates in Queens and they have a floor to area ratio of 0.5.
Where as major thoroughfares in Manhattan are R9 and R10 districts which have floor to area ratios of 7.5 and 10 respectively.
This floor to area ratio rule put pressure on designers to allocate more space to open plazas or other public spaces around the building to faciltate a taller tower, whereas the 1916 zoning laws resulted in tiered buildings that started right on the sidewalk.
The 1961 zoning code encouraged privately owned public space to ease the density and claustrophobia of a high rise city and I think we can all agree that is a move in the right
direction.
Zoning regulations like this are important to prevent brainless growth that destroy a city’s character, but sometimes they are overzealous and prevent modernisation altogether.
Take Washington DCs zoning code that has been in place for over 100 years with little change.
The Height of Buildings act of 1910 prevents any building beyond 40 metres in height.
That is incredibly restrictive and it has resulted in a city where the tallest structure is a giant stone obelisk and this thing.
Even with a relatively small population, Washington has some of the worst traffic in the US.
A study released this year by INRIX found that the people of Washington waste an average of 75 hours per year in traffic.
That means their journeys take 75 hours more than if there was no congestion.
They were second only to Los Angeles, who waste an average of 81 hours a year in traffic.
LA is often singled out as the key example of this problem of unchecked outward growth.
It was a key theme in the movie “Her”, where the car dominated urban sprawl of the present is juxtaposed with a vision of a glossy, clean, high rise future for LA.
The main character Theodore lives in a highly developed downtown LA.
He lives in a high rise building and works in a high rise building.
He’s able to walk between them and cars seem to have ceased to exist,he instead uses the extensive metro system to get around.
The movie even designed a futuristic subway map of LA.
To create this vision of the future, the producers digitally enhanced the cities existing skyline.
While also mixing in shots from present day LA with numerous shots from Shanghai’s Pudong district, like this pedestrian sky bridge which allowed Spike Jonze to film Theodore wandering through the urban jungle without having the cars at street level interfering with the illusion of a city that has transcended the need for personal transport.
That transformative change seems implausible and not likely in the near future, but cities can undergo metamorphosis when money and regulations are not an issue.
Take the mid-19th century renovation of Paris as an example.
Paris was once described by one of it’s residents as “an immense workshop of putrefaction, where misery, pestilence and sickness work in concert, where sunlight and air rarely
penetrate.
A terrible place where plants shrivel and perish, and where, of seven small infants, four die during the course of the year.”
This is an incredibly stark description of Paris, when present day Paris is often fawned over for it’s wide boulevards, amazing architecture and extensive public transport system.
Paris of old was plagued with problems caused by the outdated planning of it’s medieval past.
Paris was in need of renovation and Napolean III made it possible by giving the money and power needed to Baron Haussmann.
He transformed these narrow streets and old dilapidated buildings into spacious boulevards.
(Rue de Rivoli)
He revamped all of these streets in red and created two new parks for the cities residents.
Napolean III and Haussmann helped transform Paris into the charming city of light that 16 million tourists now visit every year.
But it may be time to start rethinking Paris’ city planning once again.
The lack of housing in central Paris has caused prices to raise so high that only the rich can afford it.
Forcing the working class families of Paris to the outskirts of the city.
Creating huge disparity of wealth between the centre and outskirts.
This map shows the concentration of social housing as a percentage of total residences, with the largest percentages being located furthest from the city centre and even now
these people are being forced further outside the city limits as gentrification occurs.
Paris is no stranger to revolts of the working class with notable riots in 1968, 2006 and just this year Paris saw more riots as new labour laws were passed giving employers more
power to increase working hours, decrease holidays and decrease pay.
The lack of affordable housing compounds these social problems and the main cause of these prices is Parisians unwillingness to build over existing buildings.
During Haussmann's renovation of paris height restrictions on buildings were raised from 16.5 to 19 metres, but the transformation of Paris took place in a time where elevators
did not exist.
In 1967 the height restrictions were lifted and the Montparnasse Tower was constructed soon after.
A building that is loathed by Parisians.
It sticks out from the surrounded buildings like a sour thumb.
There is a fine line between progress and regression.
Paris renovated to rid itself of the claustrophobic narrow streets of the past, building higher without thought will bring it right back to that.
The construction of this building resulted in the height restriction being reduced to 25 metres for central Paris.
France is a heavily regulated country and when it’s rulers decide they don’t want change, change will not occur.
But one part of Paris proves that modern high rise buildings can be introduced without destroying the character of the city.
La Défense is Europe’s largest purpose built business district housing 180,000 daily workers.
La Défense proves that skyscrapers can be incorporated into the historic background of Paris without destroying it’s charm, but La Défense is a financial district.
It was built to create office space and houses just 25,000 permanent residents.
There is little motivation to build high rise buildings to reduce housing prices as it is cheaper to push people to the outskirts of the city.
Paris is not alone in these problems, London has been criticised for the same problems and Vice News made an excellent documentary about the effects of this gentrification of working class neighbourhood.
There is no easy way of balancing preservation and growth, but we need to put our countries leaders under more pressure to consider this and not just follow the cheap easy route,
because the problems will only get worse as our populations grow.
If we allowed those height restrictions to stop us from building on 5th Avenue, the world would have been deprived of iconic buildings like the Empire State and Flat Iron Buildings.
Great cities are not static, they constantly change and move with the times.
The greatest of our modern cities like New York and Singapore function because their height enables a huge number of people to work and live on a small piece of land.
That is something our world is going to need going forward as our populations continue to grow.
Thanks for reading.
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