In the next year, expectto see a lot of announcements from companies like Ollie, which manages and develops co-living apartments, in which renters double and triple up with roommates in share suites.

Ollie now operates two co-living apartment buildings with a total of 252 beds. The company has signed deals with developers to build another eight buildings that will include co-living apartments, including a new 40-story building in the Long Island City neighborhood of Queens, N.Y. Theres also a new building that pre-leasing 166 co-living beds that will open in Pittsburgh, Penn. this fall.

The secret behind Ollies co-living revolution is that co-living is not really revolutionary. Roommates already live together in apartments across the country. “Co-living is extremely prevalent in the informal housing market in New York City,” says Sarah Watson, deputy director with the Citizens Housing Planning Council, based in New York City.