Of course there are. That's not what I meant. It's not like you're forbidden from building a basement just because you don't have to have one. But basements are a helluva lot more expensive than a second-story, and they're less marketable (lack of sunlight, for example). But where it freezes, the foundation of the home must be below the frost line. In NYC, for example, that's four feet . . . and the foundation has to go deeper than that. And many places get a lot colder than NYC. So they build basements there as a matter of course, not just because someone wants a basement.