International Building Code Section 506


International Building Code 506.1

GENERAL BUILDING HEIGHTS AND AREAS

General. The areas limited by Table 503 shall be permitted
to be increased due to frontage (If) and automatic sprinkler
system protection (Is) in accordance with the following:
(Equation 5-1)
where:
Aa = Allowable area per story (square feet).
At = Tabular area per story in accordance with Table 503
(square feet).
If = Area increase factor due to frontage as calculated in
accordance with Section 506.2.
Is = Area increase factor due to sprinkler protection as calculated
in accordance with Section 506.3.

International Building Code 506.1.1

Basements. A single basement that is not a story
above grade plane need not be included in the total allowable
area, provided such basement does not exceed the area
permitted for a building with no more than one story above
grade plane.

International Building Code 506.2

Frontage increase. Every building shall adjoin or have
access to a public way to receive an area increase for frontage.
Where a building has more than 25 percent of its perimeter on a
public way or open space having a minimum width of 20 feet
(6096 mm), the frontage increase shall be determined in accordance
with the following:
(Equation 5-2)
where:
I f = Area increase due to frontage.
F = Building perimeter that fronts on a public way or open
space having 20 feet (6096 mm) open minimum width
(feet).
P = Perimeter of entire building (feet).
W = Width of public way or open space (feet) in accordance
with Section 506.2.1.

International Building Code 506.2.1

Width limits. “W” must be at least 20 feet (6096
mm). Where the value ofWvaries along the perimeter of the
building, the calculation performed in accordance with
Equation 5-2 shall be based on the weighted average of each
portion of exteriorwall and open space where the value ofW
is greater than or equal to 20 feet (6096 mm). Where W
exceeds 30 feet (9144 mm), a value of 30 feet (9144 mm)
shall be used in calculating the weighted average, regardless
of the actual width of the open space.
Exception: The quantity ofWdivided by 30 shall be permitted
to be a maximum of 2 when the building meets all
requirements of Section 507 except for compliance with
the 60-foot (18 288 mm) publicway or yard requirement,
as applicable.

International Building Code 506.2.2

Open space limits. Such open space shall be either
on the same lot or dedicated for public use and shall be
accessed from a street or approved fire lane.

International Building Code 506.3

Automatic sprinkler system increase. Where a building
is equipped throughout with an approved automatic sprinkler
system in accordance with Section 903.3.1.1, the area
limitation in Table 503 is permitted to be increased by an additional
200 percent (Is = 2) for buildings with more than one
story above grade plane and an additional 300 percent (Is = 3)
for buildings with no more than one story above grade plane.
These increases are permitted in addition to the height and
story increases in accordance with Section 504.2.
Exception: The area limitation increases shall not be permitted
for the following conditions:
1. The automatic sprinkler system increase shall not
apply to buildings with an occupancy in Use Group
H-1.
2. The automatic sprinkler system increase shall not
apply to the floor area of an occupancy in Use Group
H-2 or H-3. For mixed-use buildings containing such
occupancies, the allowable area shall be calculated in
accordance with Section 508.3.3.2, with the sprinkler
increase applicable only to the portions of the building
not classified as Use Group H-2 or H-3.
3. Fire-resistance rating substitution in accordance with
Table 601, Note e.

International Building Code 506.4

Area determination. The maximum area of a building
with more than one story above grade plane shall be determined
by multiplying the allowable area of the first story (Aa),
as determined in Section 506.1, by the number of stories above
grade plane as listed below:
1. For buildings with two stories above grade plane, multiply
by 2;
2. For buildings with three or more stories above grade
plane, multiply by 3; and
3. No story shall exceed the allowable area per story (Aa), as
determined in Section 506.1, for the occupancies on that
story.
Exceptions:
1. Unlimited area buildings in accordance with
Section 507.
2. The maximum area of a building equipped
throughout with an automatic sprinkler system
in accordance with Section 903.3.1.2 shall be
determined by multiplying the allowable area
per story (Aa), as determined in Section 506.1,
by the number of stories above grade plane.

International Building Code 506.4.1

Mixed occupancies. In buildings with mixed occupancies,
the allowable area per story (Aa) shall be based on
the most restrictive provisions for each occupancy when the
mixed occupancies are treated according to Section 508.3.2.
When the occupancies are treated according to Section
508.3.3 as separated occupancies, the maximum total building
area shall be such that the sum of the ratios for each such
area on all floors as calculated according to Section
508.3.3.2 shall not exceed 2 for two-story buildings and 3
for buildings three stories or higher.

International Building Code 507.10

Motion picture theaters. In buildings of Type II construction,
the area of a one-story motion picture theater shall
not be limited when the building is provided with an automatic
sprinkler system throughout in accordance with Section
903.3.1.1 and is surrounded and adjoined by public ways or
yards not less than 60 feet (18 288 mm) in width.

International Building Code 507.1

General. The area of buildings of the occupancies and
configurations specified herein shall not be limited.

International Building Code 507.11

Covered mall buildings and anchor stores. The area
of covered mall buildings and anchor stores not exceeding
three stories in height that comply with Section 402.6 shall not
be limited.

International Building Code 507.2

Nonsprinklered, one story. The area of a one-story,
Group F-2 or S-2 building shall not be limited when the building
is surrounded and adjoined by publicways or yards not less
than 60 feet (18 288 mm) in width.

International Building Code 507.3

Sprinklered, one story. The area of a one-story, Group
B, F, M or S building or a one-story Group A-4 building, of
other than Type V construction, shall not be limited when the
building is provided with an automatic sprinkler system
throughout in accordance with Section 903.3.1.1 and is surrounded
and adjoined by public ways or yards not less than 60
feet (18 288 mm) in width.
Exceptions:
1. Buildings and structures of Type I and II construction
for rack storage facilities that do not have access by
the public shall not be limited in height, provided that
such buildings conform to the requirements of Sections
507.2 and 903.3.1.1 and NFPA 230.
2. The automatic sprinkler system shall not be required
in areas occupied for indoor participant sports, such
as tennis, skating, swimming and equestrian activities
in occupancies in Group A-4, provided that:
2.1. Exit doors directly to the outside are provided
for occupants of the participant sports areas;
and
2.2. The building is equipped with a fire alarm system
with manual fire alarm boxes installed in
accordance with Section 907.
3. Group A-1 and A-2 occupancies of other than TypeV
construction shall be permitted, provided:
3.1. All assembly occupancies are separated from
other spaces as required for separated uses in
Section 508.3.3.4 with no reduction allowed
in the fire-resistance rating of the separation
based upon the installation of an automatic
sprinkler system;
3.2. Each Group A occupancy shall not exceed the
maximum allowable area permitted in Section
503.1; and
3.3. All required exits shall discharge directly to
the exterior.

International Building Code 507.4

Two story. The area of a two-story, Group B, F, M or S
building shall not be limited when the building is equipped
throughout with an automatic sprinkler system in accordance
with Section 903.3.1.1, and is surrounded and adjoined by public
ways or yards not less than 60 feet (18 288 mm) in width.

International Building Code 507.5

Reduced open space. The permanent open space of 60
feet (18 288 mm) required in Sections 507.2, 507.3, 507.4,
507.6 and 507.10 shall be permitted to be reduced to not less
than 40 feet (12 192 mm), provided the following requirements
are met:
1. The reduced open space shall not be allowed for more
than 75 percent of the perimeter of the building.
2. The exterior wall facing the reduced open space shall
have a minimum fire-resistance rating of 3 hours.
3. Openings in the exterior wall facing the reduced open
space shall have opening protectives with a minimum
fire protection rating of 3 hours.

International Building Code 507.6

Group A-3 buildings. The area of a one-story, Group
A-3 building used as a place of religious worship, community
hall, dance hall, exhibition hall, gymnasium, lecture hall,
indoor swimming pool or tennis court of Type II construction
shall not be limited when all of the following criteria are met:
1. The building shall not have a stage other than a platform.
2. The building shall be equipped throughout with an automatic
sprinkler system in accordance with Section
903.3.1.1.
3. The assembly floor shall be located at or within 21 inches
(533 mm) of street or grade level and all exits are provided
with ramps complying with Section 1010.1 to the
street or grade level.
4. The building shall be surrounded and adjoined by public
ways or yards not less than 60 feet (18 288 mm)in width.

International Building Code 507.7

Group H occupancies. Group H-2, H-3 and H-4 occupancies
shall be permitted in unlimited area buildings containing
Group F and S occupancies, in accordance with Sections
507.3 and 507.4 and the limitations of this section. The aggregate
floor area of the Group H occupancies located at the perimeter
of the unlimited area building shall not exceed 10
percent of the area of the building nor the area limitations for
the Group H occupancies as specified in Table 503 as modified
by Section 506.2, based upon the percentage of the perimeter
of each GroupHfire area that fronts on a street or other unoccupied
space. The aggregate floor area of Group H occupancies
not located at the perimeter of the building shall not exceed 25
percent of the area limitations for the Group H occupancies as
specified in Table 503. Group H fire areas shall be separated
from the rest of the unlimited area building and from each other
in accordance with Table 508.3.3 For two-story unlimited area
buildings, the Group H fire areas shall not be located above the
first story unless permitted by the allowable height in stories
and feet as set forth in Table 503 based on the type of construction
of the unlimited area building.

International Building Code 507.8

Aircraft paint hangar. The area of a one-story, Group
H-2 aircraft paint hangar shall not be limited where such air-
craft paint hangar complies with the provisions of Section
412.4 and is entirely surrounded by public ways or yards not
less in width than one and one-half times the height of the
building.

International Building Code 507.9

Group E buildings. The area of a one-story Group E
building of Type II, IIIA or IV construction shall not be limited
when the following criteria are met:
1. Each classroom shall have not less than two means of
egress, with one of the means of egress being a direct exit
to the outside of the building complying with Section
1018.
2. The building is equipped throughout with an automatic
sprinkler system in accordance with Section 903.3.1.1.
3. The building is surrounded and adjoined by public ways
or yards not less than 60 feet (18 288 mm) in width.