The category includes apartment buildings with as few as two units, but does not include condos, which are typically privately owned. See how the new upzoning plan affects your neighborhood. The firm then met with the Planning Department to discuss potentially redeveloping the site to add housing atop what is currently a single-story commercial building housing the ice cream shop. The Planning Department, for its part, said development tends to occur on vacant commercial buildings and lots, not ones with profitable businesses that pay rent. For the amended plan, the same parameters apply but for buildings built before 1979 that have at least three units.