Insula (building)

In Roman architecture, an insula (Latin for "island", pl.: insulae) was one of two things: either a kind of apartment building, or a city block. This article deals with the former definition, that of a type of apartment building.

Insulae housed most of the urban citizen population of ancient Rome's massive population ranging from 800,000 to 1 million inhabitants in the early imperial period. Residents of an insula included ordinary people of lower- or middle-class status (the plebeians) and all but the wealthiest from the upper-middle class (the equites).

The traditional elite and the very wealthy lived in a domus, a large single-family residence, but the two kinds of housing were intermingled in the city and not segregated into separate neighborhoods. The ground-level floor of the insula was used for tabernae, shops and businesses, with living spaces above. Like modern apartment buildings, an insula might have a name, usually referring to the owner of the building. The owners of these buildings were typically wealthy Romans, often of senators and those of similar rank. It was also possible for an insula to be owned by several people, such as Cicero, who owned a one-eighth share of an insula and presumably took in one-eighth of its revenue. The inhabitants of the insula paid rent to secure their accommodation.