N.Y. MDW Law § 11

§ 11. Dwellings damaged or moved. 1. If a multiple dwelling be damaged\nby fire or other cause to the extent of two-thirds or more of its value\nat the time of such damage exclusive of the value of the foundation,\nsuch dwelling shall not be repaired or rebuilt except in conformity with\nthe provisions of this chapter relative to dwellings erected after April\neighteenth, nineteen hundred twenty-nine.\n 2. If any non-fireproof stair in any multiple dwelling be damaged by\nfire or other cause to such extent that such stair or the first flight\nthereof above the entrance story is required to be rebuilt, such stair\nto the extent that it is required to be rebuilt shall be fire-retarded\nthroughout.\n 3. If any dwelling be moved from one lot to another, such dwelling\nshall thereupon be made to conform to all the provisions of this chapter\nrelative to light, ventilation, fire protection and egress of a dwelling\nerected after April eighteenth, nineteen hundred twenty-nine, but no\nframe building of any kind whatsoever shall be moved so as to be placed\nupon the same lot with any multiple dwelling, nor shall any multiple\ndwelling be moved so as to be placed upon the same lot with any frame\nbuilding.\n