§ 277. Occupancy permitted. Any building in any city of more than one
million persons which at any time prior to January first, nineteen
hundred seventy-seven was occupied for loft, commercial, institutional,
public, community facility or manufacturing purposes, may,
notwithstanding any other article of this chapter, or any provision of
law covering the same subject matter (except as otherwise required by
the local zoning law or resolution), be occupied in whole or in part for
joint living-work quarters for artists or general residential purposes
if such occupancy is in compliance with this article. Such occupancy
shall be permitted only if the following conditions are met and complied
with.

1. (a) The exterior walls of the building shall be non-combustible and
have a fire-resistive rating of at least three hours unless the exterior
wall or walls, measured on a horizontal plane perpendicular to said
exterior wall or walls, is a minimum of thirty feet distant in a direct
unobstructed line from another structure, except that a wet pipe
sprinkler system, with maximum sprinkler spacing of four feet, must be
provided along such wall or walls to protect exposed, unrated columns or
beams at the interior of the wall in non-fireproof buildings.

(b) Window openings in exterior walls shall conform with the
limitations of table 3-4 chapter twenty-six of the administrative code
of the city of New York, unless such windows are fire protected and
provided with either a minimum of one sprinkler head per window or
window automatic closing devices, acceptable to the department of
buildings.

2. The building (a) is of fireproof construction, as provided in
section one hundred one of this chapter, or is of class two
construction, as provided by the requirements of the building code and
regulations of the city of New York in effect prior to December sixth,
nineteen hundred sixty-eight; or

(b) if non-fireproof, does not exceed a height of six stories, and
eighty-five feet measured to the ceiling of the highest floor in a depth
of one hundred feet; or does not exceed a height of seven stories, and
eighty-five feet and a depth of one hundred feet and is wet sprinklered
throughout; and has a maximum floor area between the two hour rated
partitions constructed in accordance with section C26-504.2 of the
administrative code of the city of New York of:

(i) three thousand square feet; or

(ii) five thousand square feet if the building is six stories or less
in height and is fully wet sprinklered; or

(iii) five thousand square feet if the building is seven stories in
height and is fully wet sprinklered and has a stand pipe system; or

(iv) ten thousand square feet if the building is fully wet sprinklered
and has one hour rated ceilings.

(c) complies with the requirements of table 3-4 chapter twenty-six of
the administrative code of the city of New York for J-2 occupancy.

3. Any part of the building may be occupied for manufacturing and
commercial purposes (as permitted by local zoning law or resolution),
provided, however, that only the second story and below may be occupied
for uses listed as medium fire hazard in rules of the board of standards
and appeals implementing the labor law unless the entire building is wet
sprinklered; in addition, high fire hazard occupancies shall not be
permitted in any portion of the building.

4. All areas occupied for manufacturing or commercial purposes shall
be protected by an approved wet-pipe automatic sprinkler system. Such
wet-pipe automatic sprinkler system shall extend to and include public
hallways and stairways coincidentally serving residential occupancies.

5. All occupancies or tenancies shall be separated by a vertical fire
separation, extending to the underside of the floor above and having a
minimum fire-resistance rating of at least one hour and conform in all
respects with applicable zoning regulations. No separation shall be
required between the working and living portions of a joint living-work
quarters for artists.

6. The building (a) complies with all requirements imposed on old-law
tenements by sections two hundred twelve and two hundred sixteen of this
chapter and on converted dwellings by sections one hundred eighty-five,
one hundred eighty-six, one hundred eighty-eight, one hundred
eighty-nine, one hundred ninety, one hundred ninety-one and one hundred
ninety-four of this chapter, in addition to those provided in section
two hundred seventy-eight of this article and (b) complies with the
standards of lighting, ventilation, size of rooms, alcoves and balconies
contained in section C26-1205.0 through and including sections
C26-1205.5 and C26-1205.7 of the administrative code of the city of New
York, except as otherwise provided in paragraph (d) of subdivision seven
of this section.

7. Minimum light and air standards for joint living-work quarters for
artists or general residential portions of lofts or manufacturing and
commercial buildings altered to residential use shall comply with the
following:

(a) Portions of such buildings which are occupied exclusively as joint
living-work quarters for artists as permitted by local law shall comply
with the following:

(i) The minimum size of a joint living-work quarters for artists shall
be twelve hundred square feet of interior space, except as otherwise
authorized by the zoning resolution of the city of New York, for units
occupied for residential purposes on or before January first, nineteen
hundred eighty-five.

(ii) Joint living-work quarters for artists shall conform to the
standards for light and ventilation of sections C26-1205.0 through and
including section C26-1205.7 of the administrative code of the city of
New York.

(b) Portions of such buildings which are occupied exclusively as
residential units as permitted by local law shall comply with the
following:

(i) Every dwelling unit shall have one or more windows:

A. which open onto a street, a court with a dimension of fifteen feet
perpendicular to the windows and one hundred square feet minimum area
above a setback or a thirty foot rear yard; or

B. for corner lots or lots within one hundred feet of a corner, where
the minimum horizontal distance between such windows opening onto a rear
yard and the rear lot line is at least twenty feet; or

C. for interior lots, where the minimum horizontal distance between
such windows opening onto a rear yard and any wall opposite such windows
on the same or another zoning lot is at least twenty feet and not less
than a distance equal to one-third of the total height of such wall
above the sill height of such windows; but need not exceed forty feet;
or

D. for interior lots where the minimum horizontal distance between
such windows opening onto a rear yard and any wall opposite such windows
on the same or another zoning lot is at least fifteen feet and the
minimum size of such dwelling unit is twelve hundred square feet; or

E. in no event shall the distance between such windows and the rear
lot line be less than five feet; and

F. yards and courts may be existing or may be new in buildings seven
stories or less in height.

(ii) The minimum required ratio of window area opening onto a street,
rear yard, or court to the floor area of every living room shall:

A. be ten percent where the floor area of such living room is less
than five hundred square feet; or

B. decrease, by one percent for every one hundred square feet greater
than five hundred square feet of floor area of such living room, to a
minimum of five percent; and

C. in no event shall the distance between such window area and the
rear lot line be less than five feet; and

D. at least fifty percent of the required window area shall be
openable.

(c) Ventilation of spaces other than living rooms, including enclosed
work spaces for joint living-work quarters for artists shall be either
in accordance with this section or in accordance with the administrative
code of the city of New York.

(d) No building converted pursuant to this article shall be enlarged,
except where the underlying zoning district permits residential use.
Such an enlargement shall be in conformance with the bulk regulations
for conforming residential use for new construction and shall be in
conformance with the provisions of section twenty-six of this chapter.
No interior floor area enlargement shall be permitted except that a
mezzanine with a minimum headroom of seven feet shall be allowed within
individual dwelling units, provided that the gross floor area of such
mezzanine does not exceed one-third of the floor area contained within
such dwelling unit. No mezzanine shall be included as floor area for the
purpose of calculating the minimum required size of a living room or a
dwelling unit or for calculating floor area devoted to dwellings. For
the purpose of this article a mezzanine may be constructed above the
level of the roof of a building as long as the aggregate area of roof
structures does not exceed one-third of the total roof area and the roof
structures conform with applicable building code requirements.

(e) The kitchen located within dwelling units and having a floor area
of eighty square feet or more shall have natural ventilation as
prescribed in sections 27-749 and 27-750 of chapter twenty-seven of the
administrative code of the city of New York. Open kitchens shall be
considered as part of the adjacent space where forty percent of the area
of the separation between the spaces is open and without doors. If the
floor area of the combined space exceeds seven hundred fifty square
feet, a separate bedroom shall not be required. When the floor area is
less than eighty square feet the kitchenette shall be ventilated by
either of the following:

(i) Natural means complying with sections 27-749 and 27-750 of chapter
twenty-seven of the administrative code of the city of New York and
further that the windows shall have a minimum width of twelve inches, a
minimum area of three square feet, or ten percent of the floor area of
the space, whichever is greater and be so constructed that at least
one-half of their required area may be opened. When the space is
located at the top story, the window or windows may be replaced with a
skylight whose minimum width shall be twelve inches, whose minimum area
shall be four square feet or one-eighth of the floor area of the space,
whichever is greater and which shall have ventilation openings of at
least one-half of the required area of the skylight.

(ii) Mechanical means exhausting at least two cubic feet per minute of
air per square foot of floor area. Where doors are to be used to
separate the space, the lower portion of each door shall have a metal
grill containing at least forty-eight square inches of clean openings or
in lieu of such grill, two clear opening spaces may be provided, each of
at least twenty-four square inches, one between the bottom of each door
and the floor and the other between the top of each door and the head
jamb.

(f) When bathrooms and toilet rooms are ventilated by natural means,
the natural ventilation sources shall comply with sub-article 1205.0 of
chapter twenty-six of the administrative code of the city of New York
and shall have an unobstructed free area of at least five percent of the
floor area. In no case shall the net free area of the ventilation
sources be less than one and one-half square feet. When bathrooms and
toilet rooms are vented by mechanical means, individual vent shafts or
ducts constructed of non-combustible materials with a minimum cross
section area of one square foot shall be utilized, the exhaust system
shall be capable of exhausting at least fifty cubic feet per minute of
air. Means shall be provided for egress of air by louvers in doors, by
undercutting the door, or by transfer ducts, grills or other openings.
Toilet exhaust systems shall be arranged to expel air directly to the
outdoors.

(g) A single station smoke detector shall be installed immediately
outside each sleeping or bedroom area of each dwelling unit. Such device
shall be designed and installed so as to detect smoke and activate an
alarm, be reasonably free from false alarms and provide visible
indication that the alarm is energized. Such device shall be directly
connected to the lighting circuit of the dwelling or rooming unit with
no intervening wall switch and shall provide a warning signal clearly
audible in all sleeping quarters with intervening doors closed. Cord
connected installations or smoke detectors which rely exclusively on
batteries are not permissible. Such devices shall either be approved or
listed by an acceptable testing service or laboratory.

8. All openings from apartments leading into a public hall or corridor
shall be provided with fireproof doors and assemblies with the doors
self-closing. Partitions between apartments on each floor shall be one
hour fire rated partitions. All windows opening on fire escapes shall be
provided with wire glass, unless such windows are protected by a wet
pipe sprinkler head with a minimum of one head per window.

9. Such buildings, in regard to egress, shall comply with the
following:

(a) In a non-fireproof building there shall be:

(i) one independently enclosed stairway and a fire escape from each
dwelling unit; or

(ii) where the building is fully wet sprinklered and not in excess of
seventy-five feet in height and not exceeding five thousand square feet
in building area one independently enclosed stairway from each dwelling,
and an independently enclosed hallway, of one hour fire rating where
there are two or more tenants on a floor; or

(iii) a sprinklered enclosed hallway with access to two independently
enclosed stairs.

(b) In a fireproof building, there shall be:

(i) an enclosed hallway and two independently enclosed stairs; or

(ii) an enclosed hallway and one independently enclosed stair and a
screened exterior stair in conformance with section two hundred
sixty-eight of the labor law with all glazed openings thereon equipped
with wire glass; or

(iii) for buildings not exceeding seven stories or seventy-five feet
in height, egress conforming with the provisions of paragraph (a) of
this subdivision; or

(iv) egress conforming with the provisions of section one hundred two
of this chapter.

(c) No more than two dwelling units shall open directly to a stair
without an intervening enclosed hallway.

(d) Enclosed hallways shall have a one hour fire rating.

(e) Enclosed stairways shall be:

(i) one hour fire rated in non-fireproof buildings four stories or
less in height; or

(ii) one hour fire rated and sprinklered in non-fireproof buildings
six stories or less in height; or

(iii) one hour fire rated in non-fireproof, fully sprinklered
buildings seven stories in height; or

(iv) two hour fire rated in all other cases.

(f) The travel distance to the means of egress shall comply with

the administrative code of the city of New York.

(g) Wooden stairs permitted by section one hundred eighty-nine of this
chapter may be retained only if, in addition to meeting all of the
requirements set forth therein, they are within a fully wet-sprinklered
enclosure, and the stair and landing soffit are fire retarded,
notwithstanding any other provisions.

(h) Every required stair shall extend through the roof by a bulkhead,
except that a scuttle may be used if the dwelling does not exceed four
stories and except that no bulkhead or scuttle is required where the
roof is a peak roof with a pitch of more than fifteen degrees.

(i) Mezzanines shall be provided with a stair at least two feet six
inches wide terminating not more than twenty feet from an exit door or
fire escape, and all portions of such mezzanines shall be not more than
fifty feet from such exit door or fire escape.

10. In buildings in excess of two stories in height, stairways shall
be provided with skylights at least twenty square feet in area, glazed
with plain glass with a wire screen over and under and provided with
fixed or movable ventilators having a minimum open area of one hundred
forty-four square inches. In lieu of the skylight and ventilators, a
window of equal area may be provided with fixed louvers having a minimum
open area of one hundred forty-four square inches installed in or
immediately adjacent to the window.

11. Except as otherwise provided in this article, all shafts shall be
enclosed with incombustible material of two hour fire rating and comply
with the administrative code of the city of New York, provided, however,
existing shaft enclosures constructed in part of combustible material
may be retained if upgraded to obtain a two hour fire rating.

12. Every kitchen or kitchenette or cooking space in such building
shall comply with the requirements imposed on multiple dwellings erected
after April eighteenth, nineteen hundred twenty-nine by section
thirty-three of this chapter.

13. Such building shall comply with all requirements imposed on
multiple dwellings erected after April eighteenth, nineteen hundred
twenty-nine by title three of article three of this chapter.

14. All interior iron columns in unsprinklered buildings shall be
protected by materials or assemblies having a fire-resistive rating of
at least three hours. Where sprinklers are provided for an exterior wall
as provided in subdivision one of this section or in a fully wet
sprinklered building such columns shall be protected by two sprinkler
heads located eighteen inches or more away and each on opposite sides of
such column but no further than four feet. Such sprinklers shall be
provided at any interior column where fire protection is omitted in
non-fireproof buildings.

15. The elevator shafts in such buildings shall be enclosed with
incombustible material of two hour fire rating, except that existing
elevator shaft enclosures constructed in part of combustible material
may be retained if upgraded to obtain a two hour fire rating; and have
fireproof doors and assemblies with (a) the doors self-closing; or (b) a
vestibule the walls of which shall be of non-combustible material and
have a minimum two hour fire resistive rating, with self-closing
fireproof doors and be fire-stopped; or (c) where the elevator is
manually operated in fully sprinklered buildings have fireproof doors,
with approved interlock devices.

16. The requirements and standards prescribed in this section shall be
subject to variation in specific cases by the commissioner of buildings,
or the board of standards and appeals, of such city under and pursuant
to the provisions of paragraph two of subdivision b of section six
hundred forty-five and section six hundred sixty-six of the New York
city charter.