Florence has no shortage of stunningly preserved historic homes—but a modern residence carved from a former theater tower, complete with a glass-bottom indoor swimming pool suspended in midair, is something else entirely.
When architect Stefano Tozzi set out to find a home more than a decade ago, he had one priority: sweeping views across the city. However, his broker insisted he look at an unusual option in the city’s bohemian Santo Spirito neighborhood, a cavernous space in…

