International Building Code Section 505

International Building Code 505.5.2

GENERAL BUILDING HEIGHTS AND AREAS

Fire suppression. Where located in a building
that is required to be protected by an automatic sprinkler
system, equipment platforms shall be fully protected by
sprinklers above and below the platform, where required by
the standards referenced in Section 903.3.

International Building Code 505.1

General. A mezzanine or mezzanines in compliance
with Section 505 shall be considered a portion of the story
below. Such mezzanines shall not contribute to either the building
area or number of stories as regulated by Section 503.1. The
area of the mezzanine shall be included in determining the fire
area defined in Section 702. The clear height above and below
the mezzanine floor construction shall not be less than 7 feet
(2134 mm).

International Building Code 505.2

Area limitation. The aggregate area of a mezzanine or
mezzanines within a room shall not exceed one-third 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 and
structures of Type I or II construction for special
industrial occupancies in accordance with Section
503.1.1 shall not exceed two-thirds of the area of the
room.
2. The aggregate area of mezzanines in buildings and
structures of Type I or II construction shall not exceed
one-half of the area of the room in buildings and
structures equipped throughout with an approved
automatic sprinkler system in accordance with Section
903.3.1.1 and an approved emergency
voice/alarm communication system in accordance
with Section 907.2.12.2.

International Building Code 505.3

Egress. Each occupant of a mezzanine shall have access
to at least two independent means of egress where the common
path of egress travel exceeds the limitations of Section 1014.3.
Where a stairway provides a means of exit access from a mezzanine,
the maximum travel distance includes the distance traveled
on the stairway measured in the plane of the tread nosing.
Accessible means of egress shall be provided in accordance
with Section 1007.
Exception: A single means of egress shall be permitted in
accordance with Section 1015.1.

International Building Code 505.4

Openness. A mezzanine shall be open and unobstructed
to the room in which such mezzanine is located except forwalls
not more than 42 inches (1067 mm) high, columns and posts.
Exceptions:
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 does not exceed 10.
2. A mezzanine having two or more means of egress is
not required to be open to the room in which the mezzanine
is located if at least one of the means of egress
provides direct access to an exit from the mezzanine
level.
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 does not exceed 10 percent of the mezzanine
area.
4. In industrial facilities, mezzanines used for control
equipment are permitted to be glazed on all sides.
5. In other than Groups H and I occupancies no more
than two stories in height above grade plane and
equipped throughout with an automatic sprinkler system
in accordance with Section 903.3.1.1, a mezzanine
having two or more means of egress shall not be
required to be open to the room in which the mezzanine
is located.

International Building Code 505.5

Equipment platforms. Equipment platforms in buildings
shall not be considered as a portion of the floor below.
Such equipment platforms shall not contribute to either the
building area or the number of stories as regulated by Section
503.1. The area of the equipment platform shall not be included
in determining the fire area. Equipment platforms shall not be a
part of any mezzanine and such platforms and the walkways,
stairs and ladders providing access to an equipment platform
shall not serve as a part of the means of egress from the building.

International Building Code 505.5.1

Area limitations. The aggregate area of all equipment
platforms within a room shall not exceed two-thirds of
the area of the room in which they are located. Where an
equipment platform is located in the same room as a mezzanine,
the area of the mezzanine shall be determined by Section
505.2 and the combined aggregate area of the
equipment platforms and mezzanines shall not exceed
two-thirds of the room in which they are located.

International Building Code 505.5.3

Guards. Equipment platforms shall have guards
where required by Section 1013.1.