Researchers Figure Out How Many Buildings Are on Earth

How many buildings are on our planet? Roughly 2.75 billion, as captured by a team from the Technical University of Munich. They've rolled out the most detailed 3D map of Earth's buildings to date, offering a new tool for researchers, urban planners, and disaster response teams. The map, dubbed the GlobalBuildingAtlas, includes nearly a billion more buildings than the largest previous database and captures structures in regions often overlooked in global mapping efforts, including Africa, South America, and rural zones, per a press release.

Per their paper published in Earth System Science Data, the team's work is the "first open dataset to offer high-quality, consistent, and complete building data in 2D and 3D form at the individual building level on a global scale." The models were based on satellite images. From a technical perspective, the 3D models have a 3-by-3-meter resolution, which the release describes as "30 times finer than data from comparable databases." Essentially all (97%) of the buildings are provided as Level of Detail 1 (LoD1) models, which capture the basic shape and height of each structure. While these aren't the most detailed versions possible, they're detailed enough to be useful for large-scale analysis and planning.

TUM professor Xiaoxiang Zhu, who led the work, says the database introduces a new way to measure housing and infrastructure: building volume per capita, which Zhu defines as "a measure of housing and infrastructure that reveals social and economic disparities." Some interesting details from the paper:

• Asia tops the list with an estimated 1.22 billion buildings. "This reflects both the continent's large population and the extensive urban development across countries such as China, India, and those in Southeast Asia," the researchers write.
• Africa is second with approximately 540 million buildings, then Europe (403 million), North America (295 million), South America (264 million), and Oceania (14 million).
• Africa may be second in building count, but its total building area is much lower, at 38 billion meters squared. It's topped by Asia (218 billion m2), Europe (138 billion m2), and North America (79 billion m2). South America and Oceania have 28 billion m2 and 5 billion m2, respectively.
• Side note: The paper points out the UN has estimated there are 4 billion buildings globally; the researchers believe the true number is between 2.64 billion and 2.97 billion buildings.