Mayor Michael Bloomberg on Monday launched a competition for developers to design a building with micro-units of no more than 300-square feet in Manhattan for the city’s expanding small-household population. …

Currently, regulations require new apartments be at least 450-square feet. There are currently 1 million studio and one-bedroom apartments in the city.

Many young people and professionals who flock to Manhattan resort to sharing larger apartments with others or renting illegally converted basement or cellar apartments, the mayor said. The mayor said appropriate housing is needed if the city wants to continue to reap the benefits young professionals provide.