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These data on house sizes come with a number of caveats: Different countries lump houses into different categories—Denmark, for instance, tracks the sizes of “cottages” in addition to those of other residential structures, and Redfin’s and Zillow’s figures vary based on whether they account for townhouses, condos, and the like. Some countries include only people’s primary residences in their analyses. And comparisons get further muddled by the fact that different countries have different levels of urbanization and density.

But that variance in density, in a way, is the point: Even in the absence of a uniform, universal system of measurement, America is in the top tier, globally, when it comes to the size of its citizens’ living spaces. The country attained this status in the past half century or so as a result of its peculiar history, culture, and economics.

It’s not that the U.S. has large houses because it has more land than other countries do. “People intuitively often think that this is the explanation … because America is such a big country,” Hirt told me. “Well, this is true, but Russia is a big country. Kazakhstan is a big country. Space itself doesn’t really make people do one thing or another.”

Government policies, however, do. As Hirt explains in her book Zoned in the USA: The Origins and Implications of American Land-Use Regulation, the dictates of government have for the past century effectively steered Americans toward living in detached single-family homes—the formal term for a prototypical stand-alone house with a yard.

“[A] nation of homeowners, of people who own a real share in their own land, is unconquerable,” Franklin D. Roosevelt said in 1942. Of course, it doesn’t necessarily follow that a nation of homeowners must own big houses, but a slew of policies—from the creation of the Federal Housing Administration in 1934 to the zoning mandates of individual towns and cities—fueled the growth of suburbs, and in turn the growth of the houses of which they were composed.

Many houses in postwar suburbs—such as those in the famous preplanned Levittowns—were actually quite modest, at roughly 850 square feet, says Dolores Hayden, a former professor of architecture and American studies at Yale. But over the course of the 20th century, government policy, the invention of cheaper, mass-produced building materials, marketing by home builders, and a shift in how people regarded their houses—not just as homes, but as financial assets—encouraged ever larger houses.

In the realm of house sizes, Europe is a common point of comparison to the United States, because things have played out very differently in the two regions (and because comprehensive data on house sizes in other parts of the world is harder to come by). One key difference is that America’s period of suburban expansion (which, it’s worth noting, largely excluded whole categories of Americans) coincided with the uptake of the automobile and the development of a more connected network of highways. Being able to drive farther from a city center meant cheaper land, which meant more space and bigger houses. “Partially why the Europeans really cannot yet reach—if that’s a good thing—our levels of being spread out is because they began driving later,” Hirt said.