(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 the room.
(2) Wherever walls or other portions of a structure face a window of any room and the obstructions are located less than three feet (914 mm) from the window and extend to a level above that of the ceiling of the room, the 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.
(B) 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 a minimum of 25 square feet (2.33 m2). The exterior glazing area shall be based on the total floor area being served.
(C) Common halls and stairways. Every common hall and stairway in residential occupancies, other than in one- and two-family dwellings, shall be lighted at all times with at least a 60-watt standard incandescent light bulb for each 200 square feet (19 m2) of floor area or equivalent illumination; provided that, the spacing between lights shall not be greater than 30 feet (9,144 mm). 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 foot candle (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.
(Adopted 10-11-2016)