An advanced Definition of Height

How the building mass height is transforming the world's tallest buildings.

The Building Mass Height

This page defines the parameters and rationale for "building mass height" as the official height, a criterion for measuring tall buildings that combines the advantages of other methods. Using this standard, height rankings of tall buildings reflect common perceptions more accurately and enable more fairness in comparisons of cities and skylines. Building mass heights are used in the ranking of the world's tallest buildings.

Definition of the Building Mass Height

The height of a building is measured from the lowest point where it meets the ground to its highest architectural point integrated with the shape of the building enclosure.
Ornamental design elements count in the building mass height only when their form flows directly from the walls of the building, or when the roof tapers into them.
Source: Phorio
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Frequently asked

Why does it matter how building heights are measured?

Many people, for various reasons, want to compare buildings with each other - planners and neighborhood groups want benchmarks for allowable heights in their areas; architecture fans like to rank buildings in a skyline and compare skylines against each other; fans of heights and the media want to know the tallest buildings in various places or categories.

What about protruding planes, such as screen walls?

Screen walls, fins, parapets, and other vertical planes extending from the roof of a building are counted in its height, because they clearly extend its visual impact on the skyline and require more structural support than a simple spire. Unfortunately this opens a window for various forms of "cheating" to add height to a building, so a future refinement of this rule may address this problem if it becomes necessary.

Why don't antennas count in the definition?

They do count, but in a different category ("tip height") which is generally presented as a secondary method for ranking buildings. Utility equipment like antennas, lightning rods, flagpoles, signs, and satellite dishes do not count in the main height listing because they are essentially "furniture" that can be removed or replaced at any time. Only permanent parts of a building that belong to its design are counted.

How do you research building heights?

The only reliable sources for building heights are technical drawings and direct measurement. Technical drawings released in the early stages of planning and construction need to be re-checked after a building is topped out. Our researchers invest a lot of time visiting construction sites around the world, checking blueprints in architects' offices, or when necessary getting readings from involved companies through email and phone contacts. We always try to verify that the reading accounts for the correct base elevation.

Which buildings are affected by the new rule?

Although most smaller high-rises are not affected at all, this rule affects many very famous and prominent tall buildings. Based on their old rankings when their spires were counted, the following are the 10 tallest buildings to lose ranking as a result of this rule

What is the rule for the base of a building?

On flat ground there is little question where a height measurement should start, but when a building is built on sloping ground, or along a riverbank, or in an area with raised streets, then there are all kinds of possible interpretations. Basically speaking, buildings are measured from ground level in front of the lowest exposed entrance. However a street-level entrance is preferred to one facing a sunken plaza (which is considered an artificial lowering of the ground level).

Does this definition measure only tall buildings?

No, it's meant for all types of buildings. People will occasionally want to compare shorter buildings with the world's tallest, and any comparison makes sense only if there's a consistent standard of measurement. The sponsors of list in their own databases hundreds of thousands more buildings than are shown here, and the same rules apply regardless of height.

How can I help to drive further implementation of this definition?

If you, like many others, see this definition as the most logical and satisfying way to compare building heights, we welcome your help in spreading its implementation. You can use heights based on this rule in wikis; you can blog about our definition or share it in social media; or if you work in traditional media you can spread the word.

Is there a way to submit missing heights?

Yes, you can submit missing heights or you can join the community and enter the data yourself.

Architectural and Roof Heights vs. Building Mass Height

The construction booms of the last two decades have sparked several public controversies over the philosophical justifications of competing definitions of building heights.

On one side are people who insist that a building's height should be measured to its roof, because ornamental features like spires "cheat" - they add height without contributing mass, and cannot compare with the engineering achievement of extending habitable space high above the ground.

The other side argues that design elements like spires, finials, or statues must be counted because they make an impact on the skyline, and cannot always be easily separated from the forms of the buildings underneath. Furthermore, building heights (for churches or the Chrysler Building, for example) have included ornamental tops for centuries.

Both sides have valid arguments, but most "official" lists today take the second position by default (the old "architectural height"; see red diagram) leaving many people dissatisfied. Making matters worse, many of the newest skyscrapers have tall stick-like spires that look like antennas but are counted as architectural features because existing rules provide no other way. Even people who prefer to count spires have problems with this.

In order to rank buildings sensibly, it was therefore obvious that the best qualities of both systems had to be synthesized. The new definition (the new "building mass height"; see green diagram) is not so much a compromise intended to pacify both sides; rather, for those who love building statistics, it is a necessary way to eliminate the unacceptable and counter-intuitive cases produced by previous rules.

Rankings by building mass height have been introduced the first time in November 2013.

Spread the word

Let others know about this new height definition, so it can be more widely implemented. If you like what we are doing, recommend this site and talk about it on the web.

Other Height Standards

There are many other ways to measure building heights, and ideally all of them should be recorded to offer people a greater range of options. These include the height to the tip of a building, or the height of the highest occupied floor. These alternative definitions are beyond the scope of this project, but they can be seen at here Phorio Standards.

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