A. 
Habitable spaces.
(1) 
Every habitable space shall have at least one window of approved size facing directly to the outdoors or to a court. The minimum total glazed area for every habitable space shall be 8% of the floor area of such room. Wherever walls or other portions of the structure face a window of any room and such obstructions are located less than three feet from the window and extend to a level above that of the ceiling of the room, such window shall not be deemed to face directly to the outdoors nor to a court and shall not be included as contributing to the required minimum total window area for the room.
(2) 
Exception. Where natural light for rooms or spaces without exterior glazing areas is provided through an adjoining room, the unobstructed opening to the adjoining room shall be at least 8% of the floor area of the interior room or space, but not less than 25 square feet. The exterior glazing area shall be based on the total floor area being served.
B. 
Lighting fixtures. Every public hall, interior stairway, toilet room, kitchen, bathroom, laundry room, boiler room, and furnace room shall contain at least one electric lighting fixture.
C. 
Common halls and stairways. Every common hall and stairway in residential occupancies, other than in one-family dwellings, shall be lighted at all times with at least a 60-watt standard incandescent light bulb for each 200 square feet of floor area or equivalent illumination, provided that the spacing between lights shall not be greater than 30. In other than residential occupancies, means of egress, including exterior means of egress, stairways shall be illuminated at all times the building space served by the means of egress is occupied with a minimum of one footcandle (11 lux) at floors, landings and treads.
D. 
Other spaces. All other spaces shall be provided with natural or artificial light sufficient to permit the maintenance of sanitary conditions, and the safe occupancy of the space and utilization of the appliances, equipment and fixtures.
E. 
Alternative devices. In lieu of the means for natural light and ventilation herein prescribed, artificial light or mechanical ventilation complying with the International Building Code shall be permitted.
A. 
Habitable spaces.
(1) 
Every habitable space shall have at least one openable window. The total openable area of the window in every room shall be equal to at least 45% of the minimum glazed area required in § 21.401A.
(2) 
Exception. Where rooms and spaces without openings to the outdoors are ventilated through an adjoining room, the unobstructed opening to the adjoining room shall be at least 8% of the floor area of the interior room or space, but not less than 25 square feet. The ventilation openings to the outdoors shall be based on a total floor area being ventilated.
B. 
Bathrooms and toilet rooms. Every bathroom and toilet room shall comply with the ventilation requirements for habitable spaces as required by § 21.402A, except that a window shall not be required in such spaces equipped with a mechanical ventilation system. Air exhausted by a mechanical ventilation system from a bathroom or toilet room shall discharge to the outdoors and shall not be re-circulated.
C. 
Cooking facilities.
(1) 
Unless approved through the certificate of occupancy, cooking shall not be permitted in any rooming unit or dormitory unit, and a cooking facility or appliance shall not be permitted to be present in a rooming unit or dormitory unit.
(2) 
Exception: where specifically approved in writing by the code official.
D. 
Process ventilation. Where injurious, toxic, irritating or noxious fumes, gases, dusts or mists are generated, a local exhaust ventilation system shall be provided to remove the contaminating agent at the source. Air shall be exhausted to the exterior and not be re-circulated to any space.
E. 
Clothes dryer exhaust. Clothes dryer exhaust systems shall be independent of all other systems and shall be exhausted to the exterior.
A. 
Privacy. Dwelling units, hotel units, rooming units and dormitory units shall be arranged to provide privacy and be separate from other adjoining spaces.
B. 
Minimum room widths. A habitable room, other than a kitchen, shall not be less than seven feet in any plan dimension. Kitchens shall have a clear passageway of not less than three feet between counterfronts and appliances or countefronts and walls.
C. 
Minimum ceiling heights.
(1) 
Habitable spaces, hallways, corridors, laundry areas, bathrooms, toilet rooms and habitable basement areas shall have a clear ceiling height of not less than seven feet.
(2) 
Exceptions.
(a) 
In one- and two-family dwellings, beams or girders spaced not less than four feet on center and projecting not more than six inches below the required ceiling height.
(b) 
Basement rooms in one- and two-family dwellings occupied exclusively for laundry, study or recreation purposes, having a ceiling height of not less than six feet eight inches with not less than six feet four inches of clear height under beams, girders, ducts and similar obstructions.
(c) 
Rooms occupied exclusively for sleeping, study or similar purposes and having a sloped ceiling over all or part of the room, with a clear ceiling height of at least seven feet over not less than one-third of the required minimum floor area. In calculating the floor area of such rooms, only those portions of the floor area with a clear ceiling height of five feet or more shall be included.
D. 
Bedroom requirements. Every bedroom shall comply with the following requirements:
(1) 
Area for sleeping purposes. Every bedroom occupied by one person shall contain at least 75 square feet of floor area, and every bedroom occupied by more than one person shall contain at least 50 square feet of floor area for each occupant thereof.
(2) 
Access from bedrooms.
(a) 
Bedrooms shall not constitute the only means of access to other bedrooms or habitable spaces and shall not serve as the only means of egress from other habitable spaces.
(b) 
Exception: units that contain fewer than two bedrooms.
(3) 
Water closet accessibility. Every bedroom shall have access to at least one water closet and one lavatory without passing through another bedroom. Every bedroom in a dwelling unit shall have access to at least one water closet and lavatory located in the same story as the bedroom or an adjacent story.
(4) 
Prohibited occupancy. Kitchens and non-habitable spaces shall not be used for sleeping purposes.
(5) 
Other requirements. Bedrooms shall comply with the light, ceiling, height, ventilation, room area, plumbing, water-heating requirements, heating facilities, electrical receptacle requirements, smoke detectors and emergency escape provisions of this code.
E. 
Overcrowding. Dwelling units shall not be occupied by more occupants than permitted by the minimum area requirements of Table 404.5.
Table 404.5
Minimum Area Requirements
Space
Minimum Area in Square Feet
1-2 Occupants
3-5 Occupants
6 or More Occupants
Living Room (a b)
No requirements
120
150
Dining Room (a b)
No requirements
80
100
Kitchen (b)
50
50
60
Bedrooms
Shall comply with § 21.403D(1)
NOTES:
a.
See § 21.403E(2) for combined living room/dining room spaces.
b.
See § 21.403E(1) for limitations on determining the minimum occupancy area for sleeping purposes.
(1) 
Sleeping area. The minimum occupancy area required by § 21.403E shall not be included in a sleeping area in determining the minimum occupancy area for sleeping purposes. All sleeping areas shall comply with § 21.403.
(2) 
Combined spaces. Combined living room and dining room spaces shall comply with the requirements of § 21.403E if the total area is equal to that required for separate rooms and if the space is located so as to function as a combination living room/dining room.
F. 
Efficiency unit. Nothing in this section shall prohibit an efficiency living unit from meeting the following requirements:
(1) 
A unit occupied by not more than two occupants shall have a clear floor area of not less than 220 square feet. A unit occupied by three occupants shall have a clear floor area of not less than 320 square feet. These required areas shall be exclusive of the areas required by Subsection F(2) and (3) of this section.
(2) 
The unit shall be provided with a kitchen sink, cooking appliance and refrigeration facilities, each having a clear working space of not less than 30 inches in front. Light and ventilation conforming to this code shall be provided.
(3) 
The unit shall be provided with a separate bathroom containing a water closet, lavatory, and bathtub or shower.
(4) 
The maximum number of occupants shall be two.
G. 
Food preparation. All spaces to be occupied for food preparation purposes shall contain suitable space and equipment to store, prepare and serve foods in a sanitary manner. There shall be adequate facilities and services for the sanitary disposal of food wastes and refuse, including facilities for temporary storage.