(2) When the lot of such a multiple dwelling does not run through from street to street and there is a difference in level exceeding twenty feet between the highest point of the curb in front of the dwelling and the lowest point of the curb on a street directly in the rear of the dwelling which street is within one hundred twenty-five feet of the rear line of the lot, a room below the level of the highest point of the curb in front of the dwelling may be used for living purposes provided such room opens upon a yard or a court adjoining a yard. The floor of any such room shall be at least six inches above the level of every part of every yard and court upon which such room opens and of the curb on the street in the rear of such dwelling and also of all intervening ground between the rear street and the rear lot line. Every such room shall be at least nine feet high from finished floor to finished ceiling. The required dimensions of a yard, or of a court adjoining a yard, on which such a room opens in any dwelling subject to the provisions of this sub-paragraph, shall be determined by the height of such dwelling measured from the lowest point of such yard or court.
(3) In any portion of a multiple dwelling arranged for living purposes below the curb level under authority of either of the sub-paragraphs above there shall be no wood beams, wood lintels or other wood structural members, nor shall any wood or other inflammable material be used in any partitions, furrings or ceilings. 2. Every multiple dwelling erected after April eighteenth, nineteen hundred twenty-nine, whenever the department shall deem it necessary, shall have all walls below the ground level and all cellar or lower floors damp-proofed and water-proofed. Such damp-proofing and water-proofing shall run throughout the cellar or other lowest floor and through and up the walls as high as the ground level. 3. Every cellar and basement in every multiple dwelling shall be properly lighted and ventilated to the satisfaction of the department. 4. In every multiple dwelling the cellar walls and ceilings, except in rooms occupied as provided in paragraph f of subdivision one or in subdivision six, shall either be constructed of light-colored material or be thoroughly whitewashed or painted a light color by the owner, and shall be so maintained. Such whitewash or paint shall be renewed whenever necessary, as may be determined and required by the department. 5. Notwithstanding any provisions of this section or of subdivision five of section three hundred, an apartment or room in a cellar which was occupied for living purposes at any time on or after October first, nineteen hundred fifty-two may thereafter continue to be occupied for such purposes until July first, nineteen hundred sixty-seven, in accordance with the conditions imposed by subdivision five of section two hundred sixteen. 6. An apartment in a cellar or basement of any multiple dwelling may be used for living purposes provided all of the following conditions are complied with: a. Such apartment has at least one half of its height and all of its window surfaces above every part of an "adequate adjacent space." Such "adequate adjacent space" shall be open to the sky, shall be properly drained to the satisfaction of the department, and shall be a continuous surface area outside the dwelling not less than thirty feet in its least dimension and abutting at same level, or directly below, every part of the exterior walls of such apartment and of every other apartment on the same floor. Such "adequate adjacent space" shall include only space which is located on the same lot or plot as the dwelling or on a street or public place or space. b. Every living room of such apartment is everywhere at least eight feet high from the floor to the ceiling in dwellings erected after July first, nineteen hundred fifty-seven, and seven feet in dwellings erected prior thereto. c. All parts of the exterior walls of the dwelling which are below ground level and on the same floor as such apartment or above such floor are dampproof to the satisfaction of the department and the floor of such apartment is dampproof and waterproof. d. The yard and every court of the dwelling containing such apartment are adequately drained to the satisfaction of the department. e. If any part of the apartment is below the "adequate adjacent space" referred to in paragraph a of this subdivision, all ceilings, walls and partitions of such apartment are fire-retarded or the rooms and spaces within such apartment are protected by a sprinkler system to the satisfaction of the department. f. Such apartment and every part of the floor on which it is situated meet all of the requirements which would be in effect for such floor if none of the rooms thereon were used for living purposes. g. Such apartment complies with all of the requirements for apartments in the same dwelling which are not in a cellar or basement. h. The floor on which such apartment is situated, if a cellar, shall nevertheless be counted as a story for the purpose of all requirements except those relating to the height of the dwelling.