A large number of skyscrapers have spires built on the top, particularly in some cities like New York City, Dubai, Chicago, etc, in which buildings with spires are more commonly seen.
Many of these skyscrapers are among the tallest buildings in the world, like Burj Khalifa, One World Trade Center, Taipei 101.
So why spires are added on skyscrapers? Below are a few reasons for spires built atop the buildings.
1. Increase height
Adding spire is a cheaper way to increase height of the building, the cost for a skinny mast is much cheaper than solid concrete core and habitable floors.
Developers build skyscrapers is not only for its functionality, they also want their buildings higher than others, so that to show prestige and draw more attention.
The developer of Shanghai World Financial Center had ever intended to build spires atop the building to make it higher than Taipei 101, so that their building will become the tallest building in the world by any measurement by that time. However the plan was not permitted by the local authority due to the concern of aesthetic aspects.
In 2017, US Bank Tower‘s title of tallest building in Western America being replaced by Wilshire Grand Center is all because of the spire on the latter building.
2. Ornamental purpose
Most skyscrapers having spires installed on the top is for ornamental purpose. For many buildings, spire is a necessary architectural element, these skyscrapers will look weird once the spire is removed, for example, what would it be if Chrysler Building had no spire built on it? It would appear incomplete and kind of strange.
Other buildings, like Petronas Towers, Taipei 101, featuring spire at top is all because of the same reason.
3. Lightning rod
Besides the aesthetic purpose, spires can function as lightning rod, for this every tallest cathedral constructed in Middle Age has a distinctive spire built on the top.
However, being the lightning rod is not the main purpose of spires, today rods do not need to be built in the shape of a distinctive spire any more.
It can be seen that many tallest buildings in the world don’t have spire-like rods, they can still withstand lightning strikes, some noted representatives are Ping An Finance Center (a tower originally designed to have a spire, but removed later in response to the aviation law) Golden 117, Lotte World Tower.
Antennas and masts can be used for broadcasting radio waves or television signals. Buildings like Willis Tower and Empire State Building all have signal transmitters installed on their antennas.
Conclusion: Spire is an architectural element to make the building look more appealing, and usually be used to increase the height of buildings, and can also functions as lightning rod, though it’s not the main purpose.