Excerpt: "With the scarcity of affordable housing in the city and with many New Yorkers already living in makeshift apartments, some housing advocates are calling for a new approach. They want the city to legalize at least some of these units by waiving certain laws, as the Bloomberg administration did last year to test so-called micro-units. Smaller than the current 450-square-foot minimum for studios, such micro-units are planned for a Manhattan building scheduled to open in 2015 in a pilot project.