14B-5-505  Mezzanines and equipment platforms.
The provisions of Section 505 of IBC are adopted by reference with the following modifications:
1.   Revise Section 505.2 to read:
505.2 Mezzanines.
A mezzanine or mezzanines in compliance with Section 505.2 shall be considered a portion of the story below. Such mezzanines shall not contribute to the number of stories above grade plane as regulated by Section 503.1. The area of the mezzanine shall be included in determining the building area and the fire area. The clear height above and below the mezzanine floor construction shall be not less than 7 feet (2134 mm).”
2.   Revise Section 505.2.1 to read:
505.2.1 Area limitation.
The aggregate area of a mezzanine or mezzanines within a room shall be not greater than twenty percent of the floor area of that room or space in which they are located. The enclosed portion of a room shall not be included in a determination of the floor area of the room in which the mezzanine is located. In determining the allowable mezzanine area, the area of the mezzanine shall not be included in the floor area of the room.
Exceptions:
1.   The aggregate area of mezzanines in buildings of Type I or II construction for special industrial occupancies in accordance with Section 503.1.1 shall be not greater than two-thirds of the floor area of the room.
2.   [Reserved.]
3.   The aggregate area of a mezzanine within a dwelling unit that is located in a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2 shall not be greater than one-half of the floor area of the room, provided that both:
3.1.   Except for enclosed closets and bathrooms, the mezzanine shall be open to the room in which such mezzanine is located.
3.2.   The opening to the room shall be unobstructed except for walls not more than 48 inches (1219 mm) in height, columns and posts.”
3.   Revise Section 505.2.1.1 by replacing “two-thirds” with “one-half.”
4.   Revise the exceptions to Section 505.2.3 to read:
"1.   In Group B, F, M and S occupancies in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, mezzanines or portions thereof are not required to be open to the room in which the mezzanines are located, provided that the occupant load of the aggregate area of the enclosed space is not greater than 10.
2.   [Reserved.]
3.   Mezzanines or portions thereof are not required to be open to the room in which the mezzanines are located provided that the aggregate floor area of the enclosed space is not greater than 10 percent of the allowable mezzanine area.
4.   In industrial facilities, mezzanines used for control equipment are permitted to be glazed on all sides.
5.   [Reserved.]
6.   Mezzanines in accordance with Exception 3 to Section 505.2.1."
5.   Revise Section 505.3 by replacing “stories” with “stories above grade plane.”
6.   Revise Section 505.3.1 by replacing “two-thirds” with “one-half.”
(Amend Coun. J. 2-19-20, p. 14473, Art. II, § 17)