What factors determine how tall the buildings in a city will be?

Question

What are the conditions that determine the types of buildings that will be dominant in a city (e.g. skyscrapers, several-story buildings, houses, etc.)?

I guess these conditions include history (how old the city is), location, whether it becomes a trade/business center, etc.

If I try to take example from the real world, I seem to not be able to determine what leads to e.g. a city with lots of skyscrapers.

Seismic activity and climate seem to have little to do with this, considering cities like Tokyo, San Francisco, Sydney and New York. It looks there is not a big cultural factor, because most of the cities with a lot tall buildings are in North America and eastern Asia (but not Europe). Obviously, when the space is not enough buildings will tend to be taller (e.g. Hong Kong). There seems like in North America more eastern cities have larger areas with several-story buildings, while most western cities have a downtown with skyscrapers and houses everywhere else.

I would suppose that older cities will have less very tall buildings, because there is usually less free space for such buildings and making skyscrapers was not possible until the XX century. My other guess is that the development of the tertiary sector (services) will favor gathering people more densely.

It appears that there are so many factors that it's hard to extract a general rule in order to determine what is plausable.

Answer 1

Economics determines the need for skyscrapers and geology determines how high they can go.

The growth of skyscrapers was driven by the desire of corporations to house their staffs in close proximity to the financial hub (The harbour in NYC, railing stock yards in Chicago, for example). The rising demand for limited amounts of land made it imperative to pack as much office space into a small footprint, hence skyscrapers.

Geology makes the other part of the equation. Skyscrapers need a solid footing, so if the bedrock is close to the surface, building the foundation is easy. IF the bedrock is deep, then much more expensive foundations need to be built, or a much shorter skyscraper has to be built. The New York city skyline can be used to gauge to depth of the bedrock:

Now since the need to have lots of office workers packed together is no longer a driving condition behind business, the need to build skyscrapers has become much lower. Modern corporations tend to create a "business campus" instead of a tower, and most modern towers tend to be "prestige projects". Modern technology also means that considerations like the bedrock depth can be circumvented; the Burj Khalifa only exists because the UAE has ridiculous amounts of money to spend and could afford to inject millions of cubic metres of grout into the sand to "build" the foundation for the monster.

Answer 2

The general rule is economics.

Cheap space usually will get low buildings. Low buildings cost less. If any building is done at all.

Expensive space will get higher buildings. Why? Yield and demand. High yield means that you can afford to invest a lot of money. High demand means that it is possible to create a lot of flooring and still sell or rent it out.

The centre of large cities is where you find both. And this is where you find skyscrapers, as well.

The cities with the strongest economy will have the tallest buildings because this is where the largest spending and earning power is.

That being said, there are regulations as well which usually will limit the height a building can have. Sometimes bad underground will lead to foundation problems which either keeps buildings lower or will require larger investment when creating high rises. This last factor does not have a major effect as these days geotechnical engineering allows for buildings above 100 meters in height even on the worst soil. The London Shard is a nice example.

References:
http://www.popularmechanics.com/technology/design/g1705/21-tallest-buildings-in-the-world/
http://www.citylab.com/housing/2016/06/should-dublin-build-higher/485078/
https://en.wikipedia.org/wiki/Geotechnical_engineering#Foundations
http://eandt.theiet.org/magazine/2011/09/vertical-city.cfm

Answer 3

I agree with @Bookeater that basically economic is the main factor on the average height of the building. The cost of tall building VS the cost of space. However, while this is the major factor, I would also like to add that there were also some other factor affecting the height of the building.

One famous example is the building height limitation in Kowloon City disctrict of Hong Kong before 1997. Height limitation is set as there was an airport nearby and the building cannot be too tall or it would crash with the landing planes. It was once a famous sight seeing place to have planes feel like flying right above your head, but now the limitation is gone when the airport is moved to other place in 1997.

During Qing dynasty in ancient China, buildings in Beijing cannot be taller than the tallest building in the palace. The height limitation is set as the emperor thinks that he should be the greatest and having a taller building then the palace is a humiliation.

So sometimes money and technology is not the only limitation to the height of the building.

Answer 4

One factor is purely cosmetic. Take Washington DC. Washington DC is an old city, at least in America. Its not that they can’t build skyscrapers, it is just that DC limits the height of buildings, as not to detract from the monuments. There are plenty of skyscrapers literally right next to DC in Maryland in Virginia.

Answer 5

I'd say the two determining factors are profitability and cost, resources can be imported, population affects land value but a large population will not in of itself cause tall buildings. Location is a factor but only insofar as it affects cost, building tall earthquake resistant buildings is expensive.

Nobody builds a skyscraper just for the sake of it, unless perhaps they're filthy rich and conceited and even then the construction of the skyscraper has turned a profit because the skyscraper itself is what's being sold. But normally a skyscraper is built to take advantage of high land value, the more expensive it is to rent office space or rent/buy apartments in the area the more money can be spent on the construction of the skyscraper and the more profitable a larger building will be.

Answer 6

So, no one here has really mentioned materials and construction technology. I did some quick googling to see if the internet had anything readily available.

I found this

Its focused primarily on current technology and states that a building with a footprint like the Burj Khalifa (which looks similar to a 'Y') could be constructed at least to the height of Mt. Everest, most likely significantly taller.

The two considerations the article has for practical limits that haven't been addressed are:

1.Human comfort (some people might not be comfortable being over 1 km in the air and looking out a window)

2.Elevators/Transport Technology (moving large amounts of people up and down in an efficient manner is hard and gets harder with more floors)

Another concern expressed is that (in general) as the building gets taller, the base gets wider (like a mountain). If this is a solid building, this leads to large amounts of the building having no access to natural light.

If you wanted to do research on the heights of buildings in various cities on Earth, I think you could check out the Council on Tall Buildings and Urban Habitat

One final note - I grew up in San Diego and I know the downtown there has had a height restriction for a long time due to the fact that the airport is downtown. So the existence of some other infrastructure may limit the height of buildings as well.

Answer 7

Here ya go, in ascending order of importance;

• Location Like you said Seismic activity is an important factor, but not as much as you think, California is right on the fault line, but you still see skyscrapers. Though an area no where near the fault line but on unstable ground is unlikely to have them.
• Resources Even if an area has a massive population, if they lack resources then they cannot build skyscrapers.
• Population This is the most important factor. A city with a large population is extremely likely to have skyscrapers, if the above conditions are met.

Answer 8

Supplementary answer. Yes, economics decides. But an underlying question is why do people want to cluster in the centre of a large city rather than spreading out over a wider area of cheaper low-rise offices? Especially if the city is on a plain with no geographic constraint on spreading?

The answer is almost certainly a desire to get more people within walking distance of each other than is possible with low-rise. Historically, decisions of great financial or political import need rapid on call access to a wide pool of skills, and face to face meetings between the participants. Telephones did not suffice to obviate this. Face to face is felt necessary to judge conviction and sincerity and to build trust.

But in the 21st century, will high-definition video conferencing suffice? The jury is out. It may be that the latest city centre skyscrapers will be the last, as obsolete as the ostentatiously attractive stone facades of the administrative centres of the 18th and 19th century imperial capitals. If so, important city centres of the 22nd century may be largely virtual constructs!

Answer 9

Well theoretically if you'll have enough or an unlimited base area there are no limits for the height of a building. For example you could build in a pyramid form, as high as you like, as long as you have enough material, time and workers etc..

As in reality one rarely has unlimited base area, rarely enough time or material the most important limitation would be the pressure resistance of the used material. Because wind and storms may play a role and also...

An other issue is the weight of the building, so it might sink at a certain level, if the underground isn't strong enough.

Beside all of this a skyscraper must also be able to lift more than itself.

Some specialists say that it is (actually) possible to build a building which might reach 1.5 km (twice as high as the actual highest building on earth Burj Khalifa), but then one needs to question the need or use of that? ecological and environmental Issues etc.

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On the other hand I don't think that geology plays a minor role, as I remember that in one of the documentaries I watched on TV in the 90's there was a problem due to the underground of the skyscrapers in Frankfurt am Main, so in cases they need to add some to add some levels on a special side to prevent some of them to loose it balance. But unfortunately I couldn't find any backup for this.

Answer 10

You build your imaginary world and ask others about how tall your buildings are going to be? Ok, I will tell you about an ideal world (ideal means an optimal real world rather than crazy, wasteful, imaginary one).

In real world we need density to save resources and enhance the labor separation. You save the energy, communication roads, pipes, transportaion, everything by factor of tens if compare with urban sprawl and make the dense city is the only sustainable solution. It is like 3D routing in silicon chip building: it is much faster and more efficient when you do not scatter the resources over the wide areas but place them all into one small chip, as dense as possible. It is even suffers of overheating because of excess of waste heat. You won't need any heaters in the Northern countries, which try to urban sprawl after american life style in the countries like Estonia today, if you populate people densely enough.

Now, consider the extremes. One one hand, you have everything flat and tool long roads and communications. It is an urpan sprawl and the ultimate inefficiency and waste of resources. Now, consider you pack everything into a one tall building. This will suffer from the same problem. You actually lose in density when have one single skyscraper. There must be an optimum in the middle where density (and efficiency) is maximal. It is either a cube or a sphere, the object which has the maximal volume with minimal surface area. Consider an ideal city, which is a single building with all shops, manufacturing and residential areas inside. If you have N people, you will pack them into say N*M square meter building (M square meters for each). Let's have 2 meter floors. This means that the volume is going to be 2*N*M cubic meter building. Take a cubic root of that number to compute the length, width and height of your building. The height, that you asked for, will be equal to the horizontal size of your building. It makes no sense to make too tall and slim buildings. Your city must be just as high as it is wide.