I can’t remember which thread on the forum, but someone said something like “We can’t have high towers all over the place, because apartments in them cost too much!”
It reminded me of something I read somewhere years ago that the cost per floor of a building on the same plot of land is higher for low buildings, then gets lower as they get higher to a certain point, and then get higher again.
Decades ago it was about six floors, because that is about as high as you can get without needing elevators. They added huge costs to the building, but were the only way to make money from higher floors.
Once elevator technology got cheaper, then the limiting cost was structural things like concrete strength, dealing with high winds and earthquakes, etc.
Now it seems it’s back to elevators and fire safety measures. The taller the building, the more elvators needed… until the whole bottom floor of the building is purely elevators.
Anyway, at the moment it seems the cost per floor stabilises at about 35-45 floors. After that, it gets more expensive per floor of a building to build higher, and then the economics don’t work out. So if you’re going to build an apartment block in a city and want the highest population density for the lowest cost per apartment, you should aim for about 40 floors. A 5 floor building will cost less to build in total, but over time the developer/city will make more from 40 floors. Above that the extra technicalities and costs make it not-worth-it.
Sources:
"At that point, the costs of providing an additional floor becomes greater. For example, the cost of adding the 51st floor is more than the cost of adding the 41st floor. Where that turning point is remains an open question, and, as I will show below, it seems to be different in different cities.
The economic theory of skyscrapers says that the profit maximizing developer keeps adding floors until the revenue of the last floor just equals the cost of providing it. One floor less means leaving money on the table since the revenue from another floor will be greater than the cost. Building one floor above the profit maximizing height means losing money since the cost of the last floor was greater than the revenue is generates."
https://www.degruyter.com/downloadpdf/j/remav.2015.23.issue-1/remav-2015-0002/remav-2015-0002.pdf
“When comparing optimal building heights derived from the two measures of investment effectiveness (profit and rate of return), one needs to remember that because the cost of the development and the income it can generate are related to each other, the rate of return indicates the optimum height earlier than maximum profit does. In other words, a building height obtained by maximizing the rate of return will be lower than one established by maximizing the profit - hRR<hprofit (Fig. 7).”