The provisions of this chapter control the height
and area of structures hereafter erected and additions to existing
structures.
New and existing buildings
shall be provided with approved address identification.
The address identification shall be legible and placed in a
position that is visible from the street or road fronting the
property. Address identification characters shall contrast with
their background. Address numbers shall be Arabic numbers
or alphabetical letters. Numbers shall not be spelled out. Each
character shall be a minimum of 4 inches (102 mm) high with
a minimum stroke width of 1⁄2 inch (12.7 mm). Where
required by the fire code official, address identification shall
be provided in additional approved locations to facilitate
emergency response. Where access is by means of a private
road and the building address cannot be viewed from the public
way, a monument, pole or other approved sign or means
shall be used to identify the structure. Address identification
shall be maintained.
The following terms are defined in Chapter
2:
AREA, BUILDING.
BASEMENT.
EQUIPMENT PLATFORM.
GRADE PLANE.
HEIGHT, BUILDING.
MEZZANINE.
AREA, BUILDING.
BASEMENT.
EQUIPMENT PLATFORM.
GRADE PLANE.
HEIGHT, BUILDING.
MEZZANINE.
Unless otherwise specifically modified in
Chapter 4 and this chapter, building height, number of stories
and building area shall not exceed the limits specified in Sections
504 and 506 based on the type of construction as determined
by Section 602 and the occupancies as determined by
Section 302 except as modified hereafter. Building height,
number of stories and
building area provisions shall be
applied independently. Each portion of a building separated
by one or more fire walls complying with Section 706 shall
be considered to be a separate building.
Buildings and
structures designed to house special industrial processes
that require large areas and unusual building heights to
accommodate craneways or special machinery and equipment,
including, among others, rolling mills; structural
metal fabrication shops and foundries; or the production
and distribution of electric, gas or steam power, shall be
exempt from the building height, number of stories and
building area limitations specified in Sections 504 and
506.
Two or more buildings on
the same lot shall be regulated as separate buildings or
shall be considered as portions of one building where the
building height, number of stories of each building and the
aggregate building area of the buildings are within the
limitations specified in Sections 504 and 506. The provisions
of this code applicable to the aggregate building
shall be applicable to each building.
Buildings of Type I construction
permitted to be of unlimited tabular building
heights and areas are not subject to the special requirements
that allow unlimited area buildings in Section 507
or unlimited building height in Sections 503.1.1 and 504.3
or increased building heights and areas for other types of
construction.
The height, in feet, and the number of stories
of a building shall be determined based on the type of construction,
occupancy classification and whether there is an
automatic sprinkler system installed throughout the building.
Exception: The building height of one-story aircraft hangars,
aircraft paint hangars and buildings used for the manufacturing
of aircraft shall not be limited where the
building is provided with an automatic sprinkler system or
automatic fire-extinguishing system in accordance with
Chapter 9 and is entirely surrounded by public ways or
yards not less in width than one and one-half times the
building height.
The height of unlimited
area buildings shall be designed in accordance with
Section 507.
The special provisions of Section
510 permit the use of special conditions that are
exempt from, or modify, the specific requirements of this
chapter regarding the allowable heights of buildings based
on the occupancy classification and type of construction,
provided the special condition complies with the provisions
specified in Section 510.
In a building containing mixed
occupancies in accordance with Section 508, no individual
occupancy shall exceed the height and number of story limits
specified in this section for the applicable occupancies.
The maximum height, in feet, of a
building shall not exceed the limits specified in Table 504.3.
For SI: 1 foot = 304.8 mm.
Note: UL = Unlimited; NS = Buildings not equipped throughout with an automatic sprinkler system; S = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
Exception: Towers, spires, steeples and other roof structures
shall be constructed of materials consistent with the
required type of construction of the building except where
other construction is permitted by Section 1510.2.5. Such
structures shall not be used for habitation or storage. The
structures shall be unlimited in height where of noncombustible
materials and shall not extend more than 20 feet
(6096 mm) above the allowable building height where of
combustible materials (see Chapter 15 for additional
requirements).
| OCCUPANCY CLASSIFICATION | TYPE OF CONSTRUCTION | |||||||||
| SEE FOOTNOTES | TYPE I | TYPE II | TYPE Ill | TYPE IV | TYPE V | |||||
| A | B | A | B | A | B | HT | A | B | ||
| A, B, E, F, M, S, U | NSb | UL | 160 | 65 | 55 | 65 | 55 | 65 | 50 | 40 |
| S | UL | 180 | 85 | 75 | 85 | 75 | 85 | 70 | 60 | |
| H-1, H-2, H-3, H-5 | NSc,d | UL | 160 | 65 | 55 | 65 | 55 | 65 | 50 | 40 |
| S | ||||||||||
| H-4 | NSc,d | UL | 160 | 65 | 55 | 65 | 55 | 65 | 50 | 40 |
| S | UL | 180 | 85 | 75 | 85 | 75 | 85 | 70 | 60 | |
| I-1 Condition 1, I-3 | NSd,e | UL | 160 | 65 | 55 | 65 | 55 | 65 | 50 | 40 |
| S | UL | 180 | 85 | 75 | 85 | 75 | 85 | 70 | 60 | |
| I-1 Condition 2, I-2 | NSd,f,e | UL | 160 | 65 | 55 | 65 | 55 | 65 | 50 | 40 |
| S | UL | 180 | 85 | |||||||
| I-4 | NSd,g | UL | 160 | 65 | 55 | 65 | 55 | 65 | 50 | 40 |
| S | UL | 180 | 85 | 75 | 85 | 75 | 85 | 70 | 60 | |
| R | NSd,h | UL | 160 | 65 | 55 | 65 | 55 | 65 | 50 | 40 |
| S13R | 60 | 60 | 60 | 60 | 60 | 60 | 60 | 60 | 60 | |
| S | UL | 180 | 85 | 75 | 85 | 75 | 85 | 70 | 60 | |
For SI: 1 foot = 304.8 mm.
Note: UL = Unlimited; NS = Buildings not equipped throughout with an automatic sprinkler system; S = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
- See Chapters 4 and 5 for specific exceptions to the allowable height in this chapter.
- See Section 903.2 for the minimum thresholds for protection by an automatic sprinkler system for specific occupancies.
- New Group H occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.5.
- The NS value is only for use in evaluation of existing building height in accordance with the International Existing Building Code.
- New Group I-1 and 1-3 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6. For new Group I-1 occupancies Condition 1, see Exception 1 of Section 903.2.6.
- New and existing Group I-2 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6 and Section 1103.5 of the International Fire Code
- For new Group I-4 occupancies, see Exceptions 2 and 3 of Section 903.2.6.
- New Group R occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.8.
The maximum number of stories
of a building shall not exceed the limits specified in Table
504.4.
Note: UL = Unlimited; NP = Not Permitted; NS = Buildings not equipped throughout with an automatic sprinkler system; S = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
| OCCUPANCY CLASSIFICATION | TYPE OF CONSTRUCTION | |||||||||
| SEE FOOTNOTES | TYPE I | TYPE II | TYPE III | TYPE IV | TYPE V | |||||
| A | B | A | B | A | B | HT | A | B | ||
| A-1 | NS | UL | 5 | 3 | 2 | 3 | 2 | 3 | 2 | 1 |
| S | UL | 6 | 4 | 3 | 4 | 3 | 4 | 3 | 2 | |
| A-2 | NS | UL | 11 | 3 | 2 | 3 | 2 | 3 | 2 | 1 |
| S | UL | 12 | 4 | 3 | 4 | 3 | 4 | 3 | 2 | |
| A-3 | NS | UL | 11 | 3 | 2 | 3 | 2 | 3 | 2 | 1 |
| s | UL | 12 | 4 | 3 | 4 | 3 | 4 | 3 | 2 | |
| A-4 | NS | UL | 11 | 3 | 2 | 3 | 2 | 3 | 2 | 1 |
| s | UL | 12 | 4 | 3 | 4 | 3 | 4 | 3 | 2 | |
| A-5 | NS | UL | UL | UL | UL | UL | UL | UL | UL | UL |
| s | UL | UL | UL | UL | UL | UL | UL | UL | UL | |
| B | NS | UL | 11 | 5 | 3 | 5 | 3 | 5 | 3 | 2 |
| s | UL | 12 | 6 | 4 | 6 | 4 | 6 | 4 | 3 | |
| E | NS | UL | 5 | 3 | 2 | 3 | 2 | 3 | 1 | 1 |
| s | UL | 6 | 4 | 3 | 4 | 3 | 4 | 2 | 2 | |
| F-1 | NS | UL | 11 | 4 | 2 | 3 | 2 | 4 | 2 | 1 |
| s | UL | 12 | 5 | 3 | 4 | 3 | 5 | 3 | 2 | |
| F-2 | NS | UL | 11 | 5 | 3 | 4 | 3 | 5 | 3 | 2 |
| s | UL | 12 | 6 | 4 | 5 | 4 | 6 | 4 | 3 | |
| H-1 | NSc,d | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | NP |
| S | ||||||||||
| H-2 | NSc,d | UL | 3 | 2 | 1 | 2 | 1 | 2 | 1 | 1 |
| S | ||||||||||
| H-3 | NSc,d | UL | 6 | 4 | 2 | 4 | 2 | 4 | 2 | 1 |
| S | ||||||||||
| H-4 | NSc,d | UL | 7 | 5 | 3 | 5 | 3 | 5 | 3 | 2 |
| S | UL | 8 | 6 | 4 | 6 | 4 | 6 | 4 | 3 | |
| H-5 | NSc,d | 4 | 4 | 3 | 3 | 3 | 3 | 3 | 3 | 2 |
| S | ||||||||||
| I-1 Condition 1 | NSd,e | UL | 9 | 4 | 3 | 4 | 3 | 4 | 3 | 2 |
| S | UL | JO | 5 | 4 | 5 | 4 | 5 | 4 | 3 | |
| I-1 Condition 2 | NSd,e | UL | 9 | 4 | 3 | 4 | 3 | 4 | 3 | 2 |
| S | UL | 10 | 5 | |||||||
| I-2 | NSd,f | UL | 4 | 2 | 1 | 1 | NP | 1 | 1 | NP |
| S | UL | 5 | 3 | |||||||
| I-3 | NSd,e | UL | 4 | 2 | 1 | 2 | 1 | 2 | 2 | 1 |
| S | UL | 5 | 3 | 2 | 3 | 2 | 3 | 3 | 2 | |
| I-4 | NSd,g | UL | 5 | 3 | 2 | 3 | 2 | 3 | 1 | 1 |
| S | UL | 6 | 4 | 3 | 4 | 3 | 4 | 2 | 2 | |
| M | NS | UL | 1 | 1 | 4 | 2 | 4 | 2 | 4 | 3 |
| S | UL | 12 | 5 | 3 | 5 | 3 | 5 | 4 | 2 | |
| R-1 | NSd,h | UL | 11 | 4 | 4 | 4 | 4 | 4 | 3 | 2 |
| S13R | 4 | 4 | 4 | 3 | ||||||
| S | UL | 12 | 5 | 5 | 5 | 5 | 5 | 4 | 3 | |
| R-2 | NSd,h | UL | 11 | 4 | 4 | 4 | 4 | 4 | 3 | 2 |
| S13R | 4 | 4 | 4 | 4 | 3 | |||||
| S | UL | 12 | 5 | 5 | 5 | 5 | 5 | 4 | 3 | |
| R-3 | NSd,h | UL | 11 | 4 | 4 | 4 | 4 | 4 | 3 | 3 |
| S13R | 4 | 4 | 4 | 4 | ||||||
| S | UL | 12 | 5 | 5 | 5 | 5 | 5 | 4 | 4 | |
| R-4 | NSd,h | UL | 11 | 4 | 4 | 4 | 4 | 4 | 3 | 2 |
| S13R | 4 | 4 | 4 | 3 | ||||||
| S | UL | 12 | 5 | 5 | 5 | 5 | 5 | 4 | 3 | |
| S-1 | NS | UL | 11 | 4 | 2 | 3 | 2 | 4 | 3 | 1 |
| S | UL | 12 | 5 | 3 | 4 | 3 | 5 | 4 | 2 | |
| S-2 | NS | UL | 11 | 5 | 3 | 4 | 3 | 4 | 4 | 2 |
| S | UL | 12 | 6 | 4 | 5 | 4 | 5 | 5 | 3 | |
| U | NS | UL | 5 | 4 | 2 | 3 | 2 | 4 | 2 | 1 |
| S | UL | 6 | 5 | 3 | 4 | 3 | 5 | 3 | 2 | |
Note: UL = Unlimited; NP = Not Permitted; NS = Buildings not equipped throughout with an automatic sprinkler system; S = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
- See Chapters 4 and 5 for specific exceptions to the allowable height in this chapter.
- See Section 903.2 for the minimum thresholds for protection by an automatic sprinkler system for specific occupancies.
- New Group H occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.5.
- The NS value is only for use in evaluation of existing building height in accordance with the International Existing Building Code.
- New Group I-1 and I-3 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6. For new Group I-1 occupancies, Condition 1, see Exception 1 of Section 903.2.6.
- New and existing Group I-2 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6 and Section 1103.5 of the International Fire Code.
- For new Group I-4 occupancies, see Exceptions 2 and 3 of Section 903.2.6.
- New Group R occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.8.
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 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. The clear height above and below the
mezzanine floor construction shall be not less than 7 feet
(2134 mm).
The aggregate area of a mezzanine
or mezzanines within a room shall be not greater than
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.
Where a room contains both a mezzanine and an equipment platform, the aggregate area of the two raised floor levels shall be not greater than two-thirds of the floor area of that room or space in which they are located.
Exceptions:
Where a room contains both a mezzanine and an equipment platform, the aggregate area of the two raised floor levels shall be not greater than two-thirds of the floor area of that room or space in which they are located.
Exceptions:
- 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 be not greater than twothirds of the floor area of the room.
- The aggregate area of mezzanines in buildings and structures of Type I or II construction shall be not greater than one-half of the floor 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 907.5.2.2.
A mezzanine shall be open and unobstructed
to the room in which such mezzanine is located
except for walls not more than 42 inches (1067 mm) in
height, columns and posts.
Exceptions:
Exceptions:
- 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.
- A mezzanine having two or more exits or access to exits is not required to be open to the room in which the mezzanine is located.
- 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 mezzanine area.
- In industrial facilities, mezzanines used for control equipment are permitted to be glazed on all sides.
- In occupancies other than Groups H and I, that are no more than two stories 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.
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 in accordance with Section
903. Equipment platforms shall not be a part of any mezzanine
and such platforms and the walkways, stairways,
alternating tread devices and ladders providing access to an
equipment platform shall not serve as a part of the means of
egress from the building.
The aggregate area of all equipment
platforms within a room shall be not greater than
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 505.2.1 and the combined aggregate
area of the equipment platforms and mezzanines shall
be not greater than two-thirds of the room in which they
are located.
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.
The floor area of a building shall be determined
based on the type of construction, occupancy classification,
whether there is an automatic sprinkler system
installed throughout the building and the amount of building
frontage on public way or open space.
Unlimited area buildings
shall be designed in accordance with Section 507.
The special provisions of Section
510 permit the use of special conditions that are
exempt from, or modify, the specific requirements of this
chapter regarding the allowable areas of buildings based
on the occupancy classification and type of construction,
provided the special condition complies with the provisions
specified in Section 510.
Basements need not be included in
the total allowable floor area of a building provided the
total area of such basements does not exceed the area permitted
for a one-story above grade plane building.
The allowable area of
a building shall be determined in accordance with the applicable
provisions of Sections 506.2.1 through 506.2.4 and
Section 506.3.
The
allowable area of a single-occupancy building with no
more than one story above grade plane shall be determined
in accordance with Equation 5-1:
where:
Note: UL = Unlimited; NP = Not permitted;
For SI: 1 square foot = 0.0929 m2. NS = Buildings not equipped throughout with an automatic sprinkler system; SI = Buildings a maximum of one story above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; SM = Buildings two or more stories above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
Aa = At + (NS × If)
(Equation 5-1)
where:
| Aa | = | Allowable area (square feet). |
| At | = | Tabular allowable area factor (NS, S1, or S13R value, as applicable) in accordance with Table 506.2. |
| NS | = | Tabular allowable area factor in accordance with Table 506.2 for nonsprinklered building (regardless of whether the building is sprinklered). |
| If | = | Area factor increase due to frontage (percent) as calculated in accordance with Section 506.3. |
| OCCUPANCY CLASSIFICATION |
SEE FOOTNOTES | TYPE OF CONSTRUCTION | ||||||||
| TYPE I | TYPE II | TYPE II | TYPE IV | TYPE V | ||||||
| A | B | A | B | A | B | HT | A | B | ||
| A-1 | NS | UL | UL | 15,500 | 8,500 | 14,000 | 8,500 | 15,000 | 11,500 | 5,500 |
| S1 | UL | UL | 62,000 | 34,000 | 56,000 | 34,000 | 60,000 | 46,000 | 22,000 | |
| SM | UL | UL | 46,500 | 25,500 | 42,000 | 25,500 | 45,000 | 34,500 | 16,500 | |
| A-2 | NS | UL | UL | 15,500 | 9,500 | 14,000 | 9,500 | 15,000 | 11,500 | 6,000 |
| S1 | UL | UL | 62,000 | 38,000 | 56,000 | 38,000 | 60,000 | 46,000 | 24,000 | |
| SM | UL | UL | 46,500 | 28,500 | 42,000 | 28,500 | 45,000 | 34,500 | 18,000 | |
| A-3 | NS | UL | UL | 15,500 | 9,500 | 14,000 | 9,500 | 15,000 | 11,500 | 6,000 |
| S1 | UL | UL | 62,000 | 38,000 | 56,000 | 38,000 | 60,000 | 46,000 | 24,000 | |
| SM | UL | UL | 46,500 | 28,500 | 42,000 | 28,500 | 45,000 | 34,500 | 18,000 | |
| A-4 | NS | UL | UL | 15,500 | 9,500 | 14,000 | 9,500 | 15,000 | 11,500 | 6,000 |
| S1 | UL | UL | 62,000 | 38,000 | 56,000 | 38,000 | 60,000 | 46,000 | 24,000 | |
| SM | UL | UL | 46,500 | 28,500 | 42,000 | 28,500 | 45,000 | 34,500 | 18,000 | |
| A-5 | NS | UL | UL | UL | UL | UL | UL | UL | UL | UL |
| S1 | ||||||||||
| SM | ||||||||||
| B | NS | UL | UL | 37,500 | 23,000 | 28,500 | 19,000 | 36,000 | 18,000 | 9,000 |
| S1 | UL | UL | 150,000 | 92,000 | 114,000 | 76,000 | 144,000 | 72,000 | 36,000 | |
| SM | UL | UL | 112,500 | 69,000 | 85,500 | 57,000 | 108,000 | 54,000 | 27,000 | |
| E | NS | UL | UL | 26,500 | 14,500 | 23,500 | 14,500 | 25,500 | 18,500 | 9,500 |
| S1 | UL | UL | 106,000 | 58,000 | 94,000 | 58,000 | 102,000 | 74,000 | 38,000 | |
| SM | UL | UL | 79,500 | 43,500 | 70,500 | 43,500 | 76,500 | 55,500 | 28,500 | |
| F-1 | NS | UL | UL | 25,000 | 15,500 | 19,000 | 12,000 | 33,500 | 14,000 | 8,500 |
| S1 | UL | UL | 100,000 | 62,000 | 76,000 | 48,000 | 134,000 | 56,000 | 34,000 | |
| SM | UL | UL | 75,000 | 46,500 | 57,000 | 36,000 | 100,500 | 42,000 | 25,500 | |
| F-2 | NS | UL | UL | 37,500 | 23,000 | 28,500 | 18,000 | 50,500 | 21,000 | 13,000 |
| S1 | UL | UL | 180,000 | 92,000 | 114,000 | 72,000 | 202,000 | 84,000 | 52,000 | |
| SM | UL | UL | 112,500 | 69,000 | 85,500 | 54,000 | 151,500 | 63,000 | 39,000 | |
| H-1 | NSc | 21,000 | 16,500 | 11,000 | 7,000 | 9.500 | 7,000 | 10,500 | 7,500 | NP |
| S1 | ||||||||||
| H-2 | NSc | 21,000 | 16,500 | 11,000 | 7,000 | 9.500 | 7,000 | 10,500 | 7,500 | 3,000 |
| S1 | ||||||||||
| SM | ||||||||||
| H-3 | NSc | UL | 60,000 | 26,500 | 14,000 | 17,500 | 13,000 | 25,500 | 10,000 | 5,500 |
| S1 | ||||||||||
| SM | ||||||||||
| H-4 | NSc,d | UL | UL | 37,500 | 17,500 | 28,500 | 17,500 | 36,000 | 18,000 | 6,500 |
| SI | UL | UL | 150,000 | 70,000 | 114,000 | 70,000 | 114,000 | 72,000 | 26,000 | |
| SM | UL | UL | 112,500 | 52,500 | 85,500 | 52,500 | 108,000 | 54,000 | 19,500 | |
| H-5 | NSc | UL | UL | 37,500 | 23,000 | 28,500 | 19,000 | 36,000 | 18,000 | 9,000 |
| S1 | UL | UL | IS0,000 | 92,000 | 114,000 | 76,000 | 144,000 | 72,000 | 36,000 | |
| SM | UL | UL | 112,500 | 69,000 | 85,500 | 57,000 | 108,000 | 54,000 | 27,000 | |
| I-1 | NSd,e | UL | 55,000 | 19,000 | 10,000 | 16,500 | 10,000 | 18,000 | 10,500 | 4,500 |
| S1 | UL | 220,000 | 76,000 | 40,000 | 66,000 | 40,000 | 72,000 | 42,000 | 18,000 | |
| SM | UL | 165,000 | 57,000 | 30,000 | 49,500 | 30,000 | 54,000 | 31,500 | 13,500 | |
| I-2 | NSd,f | UL | UL | 15,000 | 11,000 | 12,000 | NP | 12,000 | 9,500 | NP |
| S1 | UL | UL | 60,000 | 44,000 | 48,000 | NP | 48,000 | 38,000 | NP | |
| SM | UL | UL | 45,000 | 33,000 | 36,000 | NP | 36,000 | 28,500 | NP | |
| I-3 | NSd,e | UL | UL | 15,000 | 10,000 | 10,500 | 7,500 | 12,000 | 7,500 | 5,000 |
| S1 | UL | UL | 45,000 | 40,000 | 42,000 | 30,000 | 48,000 | 30,000 | 20,000 | |
| SM | UL | UL | 45,000 | 30,000 | 31,500 | 22,500 | 36,000 | 22,500 | 15,000 | |
| I-4 | NSd,g | UL | 60.500 | 26,500 | 13,000 | 23,500 | 13,000 | 25,500 | 18,500 | 9,000 |
| S1 | UL | 121,000 | 106,000 | 52,000 | 94,000 | 52,000 | 102,000 | 74,000 | 36,000 | |
| SM | UL | 181,500 | 79,500 | 39,000 | 70,500 | 39,000 | 76,500 | 55,500 | 27,000 | |
| M | NS | UL | UL | 21,500 | 12,500 | 18,500 | 12,500 | 20,500 | 14,000 | 9,000 |
| S1 | UL | UL | 86,000 | 50,000 | 74,000 | 50,000 | 82,000 | 56,000 | 36,000 | |
| SM | UL | UL | 64,500 | 37,500 | 55,500 | 37,500 | 61,500 | 42,000 | 27,000 | |
| R-1 | NSd,h | UL | UL | 24,000 | 16,000 | 24,000 | 16,000 | 20,500 | 12,000 | 7,000 |
| S13R | ||||||||||
| S1 | UL | UL | 96,000 | 64,000 | 96,000 | 64,000 | 82,000 | 48,000 | 28,000 | |
| SM | UL | UL | 72,000 | 48,000 | 72,000 | 48,000 | 61,500 | 36,000 | 21,000 | |
| R-2 | NSd,h | UL | UL | 24,000 | 16,000 | 24,000 | 16,000 | 20,500 | 12,000 | 7,000 |
| S13R | ||||||||||
| S1 | UL | UL | 96,000 | 64,000 | 96,000 | 64,000 | 82,000 | 48,000 | 28,000 | |
| SM | UL | UL | 72,000 | 48,000 | 72,000 | 48,000 | 61,500 | 36,000 | 21,000 | |
| R-3 | NSd,h | UL | UL | UL | UL | UL | UL | UL | UL | UL |
| S13R | ||||||||||
| S1 | ||||||||||
| SM | ||||||||||
| R-4 | NSd,h | UL | UL | 24,000 | 16,000 | 24,000 | 16,000 | 20,500 | 12,000 | 7,000 |
| S13R | ||||||||||
| S1 | UL | UL | 96,000 | 64,000 | 96,000 | 64,000 | 82,000 | 48,000 | 28,000 | |
| SM | UL | UL | 72,000 | 48,000 | 72,000 | 48,000 | 61,500 | 36,000 | 21,000 | |
| S-1 | NS | UL | 48,000 | 26,000 | 17,500 | 26,000 | 17,500 | 25,500 | 14,000 | 9,000 |
| S1 | UL | 192,000 | 104,000 | 70,000 | 104,000 | 70,000 | 102,000 | 56,000 | 36,000 | |
| SM | UL | 144,000 | 78,000 | 52,500 | 78,000 | 52,500 | 76,500 | 42,000 | 27,000 | |
| S-2 | NS | UL | 79,000 | 39,000 | 26,000 | 39,000 | 26,000 | 38,500 | 21,00 | 13,500 |
| S1 | UL | 316,000 | 156,000 | 104,000 | 156,000 | 104,000 | 154,000 | 84,000 | 54,000 | |
| SM | UL | 237,000 | 117,000 | 78,000 | 117,000 | 78,000 | 115,500 | 63,000 | 40,500 | |
| U | NS | UL | 35,500 | 19,000 | 8,500 | 14,000 | 8,500 | 18,000 | 9,000 | 5,500 |
| S1 | UL | 142,000 | 76,000 | 34,000 | 56,000 | 34,000 | 72,000 | 36,000 | 22,000 | |
| SM | UL | 106,500 | 57,000 | 25,500 | 42,000 | 25,500 | 54,000 | 27,000 | 16,500 | |
Note: UL = Unlimited; NP = Not permitted;
For SI: 1 square foot = 0.0929 m2. NS = Buildings not equipped throughout with an automatic sprinkler system; SI = Buildings a maximum of one story above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; SM = Buildings two or more stories above grade plane equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1; S13R = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2.
- See Chapters 4 and 5 for specific exceptions to the allowable height in this chapter.
- See Section 903.2 for the minimum thresholds for protection by an automatic sprinkler system for specific occupancies.
- New Group H occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.5.
- The NS value is only for use in evaluation of existing building area in accordance with the International Existing Building Code.
- New Group I-1 and I-3 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6. For new Group I-1 occupancies, Condition 1, see Exception 1 of Section 903.2.6.
- New and existing Group I-2 occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.6 and Section 1103.5 of the International Fire Code.
- New Group I-4 occupancies see Exceptions 2 and 3 of Section 903.2.6.
- New Group R occupancies are required to be protected by an automatic sprinkler system in accordance with Section 903.2.8.
The
allowable area of a mixed-occupancy building with no
more than one story above grade plane shall be determined
in accordance with the applicable provisions of Section
508.1 based on Equation 5-1 for each applicable occupancy.
For
a building containing Group H-2 or H-3 occupancies,
the allowable area shall be determined in accordance
with Section 508.4.2, with the sprinkler system
increase applicable only to the portions of the building
not classified as Group H-2 or H-3.
The
allowable area of a single-occupancy building with more
than one story above grade plane shall be determined in
accordance with Equation 5-2:
where:
No individual story shall exceed the allowable area (Aa) as determined by Equation 5-2 using the value of Sa = 1.
Aa = [At + (NS × If)] x Sa
(Equation 5-2)
where:
| Aa | = | Allowable area (square feet). |
| At | = | Tabular allowable area factor (NS, S13R or SM value, as applicable) in accordance with Table 506.2. |
| NS | = | Tabular allowable area factor in accordance with Table 506.2 for a nonsprinklered building (regardless of whether the building is sprinklered). |
| If | = | Area factor increase due to frontage (percent) as calculated in accordance with Section 506.3. |
| Sa | = | Actual number of building stories above grade plane, not to exceed three. For buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2, use the actual number of building stories above grade plane, not to exceed four. |
No individual story shall exceed the allowable area (Aa) as determined by Equation 5-2 using the value of Sa = 1.
Each
story of a mixed-occupancy building with more than one
story above grade plane shall individually comply with the
applicable requirements of Section 508.1. For buildings
with more than three stories above grade plane, the total
building area shall be such that the aggregate sum of the
ratios of the actual area of each story divided by the allowable
area of such stories, determined in accordance with
Equation 5-3 based on the applicable provisions of Section
508.1, shall not exceed three.
where:
Exception: For buildings designed as separated occupancies under Section 508.4 and equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2, the total building area shall be such that the aggregate sum of the ratios of the actual area of each story divided by the allowable area of such stories determined in accordance with Equation 5-3 based on the applicable provisions of Section 508.1, shall not exceed four.
Aa = [Aa + (NS × 1)]
(Equation 5-3)
where:
| Aa | = | Allowable area (square feet). |
| At | = | Tabular allowable area factor (NS, S13R or SM value, as applicable) in accordance with Table 506.2. |
| NS | = | Tabular allowable area factor in accordance with Table 506.2 for a nonsprinklered building (regardless of whether the building is sprinklered). |
| If | = | Area factor increase due to frontage (percent) as calculated in accordance with Section 506.3. |
Exception: For buildings designed as separated occupancies under Section 508.4 and equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.2, the total building area shall be such that the aggregate sum of the ratios of the actual area of each story divided by the allowable area of such stories determined in accordance with Equation 5-3 based on the applicable provisions of Section 508.1, shall not exceed four.
For
a building containing Group H-2 or H-3 occupancies,
the allowable area shall be determined in accordance
with Section 508.4.2, with the sprinkler system
increase applicable only to the portions of the building
not classified as Group H-2 or H-3.
Every building shall adjoin or have
access to a public way to receive an area factor increase based
on frontage. Area factor increase shall be determined in
accordance with Sections 506.3.1 through 506.3.3.
To qualify
for an area factor increase based on frontage, a building
shall have not less than 25 percent of its perimeter on a
public way or open space. 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.
To qualify for an
area factor increase based on frontage, the public way or
open space adjacent to the building perimeter shall have a
minimum distance (W) of 20 feet (6096 mm) measured at
right angles from the building face to any of the following:
where
- The closest interior lot line.
- The entire width of a street, alley or public way.
- The exterior face of an adjacent building on the same property.
W= (L1 × w1 + L2 × w2 + L3 × w3...)/F
(Equation 5-4)
where
| W | (Width: weighted average) = Calculated width of public way or open space (feet). |
|
| Ln | = | Length of a portion of the exterior perimeter wall. |
| wn | = | Width (≥ 20 feet) of a public way or open space associated with that portion of the exterior perimeter wall. |
| F | = | Building perimeter that fronts on a public way or open space having a width of 20 feet (6096 mm) or more. |
Exception: Where a building meets the requirements
of Section 507, as applicable, except for compliance
with the minimum 60-foot (18288 mm) public way or
yard requirement, and the value of W is greater than 30
feet (9144 mm), the value of W shall not exceed 60 feet
(18288 mm).
The area factor increase
based on frontage shall be determined in accordance with
Equation 5-5:
If = [ F/P - 0.25 ] W/30
(Equation 5-5)
where:
| If | = | Area factor increase due to frontage. |
| F | = | Building perimeter that fronts on a public way or open space having minimum distance of 20 feet (6096 mm). |
| P | = | Perimeter of entire building (feet). |
| W | = | Width of public way or open space (feet) in accordance with Section 506.3.2. |
The area of buildings of the occupancies and
configurations specified in Sections 507.1 through 507.12
shall not be limited. Basements not more than one story
below grade plane shall be permitted.
Accessory occupancies
shall be permitted in unlimited area buildings in accordance
with the provisions of Section 508.2, otherwise the
requirements of Sections 507.3 through 507.13 shall be
applied, where applicable.
Where Sections 507.3
through 507.13 require buildings to be surrounded and
adjoined by public ways and yards, those open spaces shall be
determined as follows :
- Yards shall be measured from the building perimeter in all directions to the closest interior lot lines or to the exterior face of an opposing building located on the same lot, as applicable.
- Where the building fronts on a public way, the entire width of the public way shall be used.
The public ways or yards of
60 feet (18288 mm) in width required in Sections 507.3,
507.4, 507.5, 507.6 and 507.12 shall be permitted to be
reduced to not less than 40 feet (12192 mm) in width provided
all of the following requirements are met:
- The reduced width shall not be allowed for more than 75 percent of the perimeter of the building.
- The exterior walls facing the reduced width shall have a fire-resistance rating of not less than 3 hours.
- Openings in the exterior walls facing the reduced width shall have opening protectives with a fire protection rating of not less than 3 hours.
The area of a
Group F-2 or S-2 building no more than one story in height
shall not be limited where the building is surrounded and
adjoined by public ways or yards not less than 60 feet (18288
mm) in width.
The area of a
Group A-4 building no more than one story above grade
plane of other than Type V construction, or the area of a
Group B, F, M or S building no more than one story above
grade plane of any construction type, shall not be limited
where 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 (18288 mm) in width.
Exceptions:
Exceptions:
- Buildings and structures of Type I or 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 507.4 and 903.3.1.1 and Chapter 32 of the International Fire Code.
- 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 both
of the following criteria are met:
- Exit doors directly to the outside are provided for occupants of the participant sports areas.
- The building is equipped with a fire alarm system with manual fire alarm boxes installed in accordance with Section 907.
Group A-1 and A-2 occupancies of other than
Type V construction shall be permitted within mixed
occupancy buildings of unlimited area complying with
Section 507.4, provided all of the following criteria are
met:
- Group A-1 and A-2 occupancies are separated from other occupancies as required for separated occupancies in Section 508.4.4 with no reduction allowed in the fire-resistance rating of the separation based upon the installation of an automatic sprinkler system.
- Each area of the portions of the building used for Group A-1 or A-2 occupancies shall not exceed the maximum allowable area permitted for such occupancies in Section 503.1.
- Exit doors from Group A-1 and A-2 occupancies shall discharge directly to the exterior of the building.
The area of a Group B, F, Mor S
building no more than two stories above grade plane sha11
not be limited where 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 (18288 mm) in width.
The
area of a Group A-3 building no more than one story above
grade plane, 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 provided all of the following criteria are
met:
- The building shall not have a stage other than a platform.
- The building shall be equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
- The building shall be surrounded and adjoined by public ways or yards not less than 60 feet (18288 mm) in width.
The area of a Group A-3 building of Type III or IV construction,
with no more than one story above grade plane and
used as a place of religious worship, community hall, dance
hall, exhibition hall, gymnasium, lecture hall, indoor swimming
pool or tennis court, shall not be limited provided all of
the following criteria are met:
- The building shall not have a stage other than a platform.
- The building shall be equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
- 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 1012 to the street or grade level.
- The building shall be surrounded and adjoined by public ways or yards not less than 60 feet (18288 mm) in width.
The aggregate floor area of
Group H occupancies located in an unlimited area building
shall not exceed 10 percent of the area of the building or
the area limitations for the Group H occupancies as specified
in Section 506 based on the perimeter of each Group
H floor area that fronts on a public way or open 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 Section 506.
Liquid use, dispensing and mixing rooms
having a floor area of not more than 500 square feet
(46.5 m2) need not be located on the outer perimeter
of the building where they are in accordance with
the International Fire Code and NFPA 30.
Liquid storage
rooms having a floor area of not more than 1,000
square feet (93 m2) need not be located on the outer
perimeter where they are in accordance with the
International Fire Code and NFPA 30.
Spray paint booths
that comply with the International Fire Code need
not be located on the outer perimeter.
Except as provided
for in Section 507.8.1.1, Group H occupancies shall
be located on the perimeter of the building. In Group H-2
and H-3 occupancies, not less than 25 percent of the
perimeter of such occupancies shall be an exterior wall.
Group H occupancies
shall be separated from the remainder of the unlimited area
building and from each other in accordance with Table
508.4.
| OCCUPANCY | A,E | I-1a, I-3, I-4 | I-2 | Ra | F-2, S-2b, U | Be, F-1, M, S-1 |
H-1 | H-2 | H-3, H-4 | H-5 | ||||||||||
| S | NS | S | NS | S | NS | S | NS | S | NS | S | NS | S | NS | S | NS | S | NS | S | NS | |
| A,E | N | N | 1 | 2 | 2 | NP | 1 | 2 | N | 1 | 1 | 2 | NP | NP | 3 | 4 | 2 | 3 | 2 | NP |
| I-1a, I-3, I-4 | - | - | N | N | 2 | NP | 1 | NP | 1 | 2 | 1 | 2 | NP | NP | 3 | NP | 2 | NP | 2 | NP |
| I-2 | - | - | - | - | N | N | 2 | NP | 2 | NP | 2 | NP | NP | NP | 3 | NP | 2 | NP | 2 | NP |
| Ra | - | - | - | - | - | - | N | N | 1c | 2c | 1 | 2 | NP | NP | 3 | NP | 2 | NP | 2 | NP |
| F-2, S-2b, U | - | - | - | - | - | - | - | - | N | N | 1 | 2 | NP | NP | 3 | 4 | 2 | 3 | 2 | NP |
| Be, F-1, M, S-1 | - | - | - | - | - | - | - | - | - | - | N | N | NP | NP | 2 | 3 | 1 | 2 | 1 | NP |
| H-1 | - | - | - | - | - | - | - | - | - | - | - | - | N | NP | NP | NP | NP | NP | NP | NP |
| H-2 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | N | NP | 1 | NP | 1 | NP |
| H-3, H-4 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 1d | NP | 1 | NP |
| H-5 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | N | NP |
| S | = | Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1. |
| NS | = | Buildings not equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1. |
| N | = | No separation requirement. |
| NP | = | Not permitted. |
- See Section 420.
- The required separation from areas used only for private or pleasure vehicles shall be reduced by 1 hour but not to less than 1 hour.
- See Section 406.3.4.
- Separation is not required between occupancies of the same classification.
- See Section 422.2 for ambulatory care facilities.
For two-story, unlimited area
buildings, Group H occupancies shall not be located more
than one story above grade plane unless permitted based
on the allowable height and number of stories and feet as
specified in Section 504 based on the type of construction
of the unlimited area building.
The area of a Group B, F, H-5, M or S building no more
than two stories above grade plane shall not be limited where
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 (18288 mm) in width, provided all of the following
criteria are met:
- Buildings containing Group H-5 occupancy shall be of Type I or II construction.
- Each area used for Group H-5 occupancy shall be separated from other occupancies as required in Sections 415.11 and 508.4.
- Each area used for Group H-5 occupancy shall not exceed the maximum allowable area permitted for such occupancies in Section 503.1 including modifications of Section 506.
Exception: Where the Group H-5 occupancy
exceeds the maximum allowable area, the Group H-5 shall be subdivided into areas that are separated by
2-hour fire barriers.
The area of a Group H-2 aircraft
paint hangar no more than one story above grade plane
shall not be limited where such aircraft paint hangar complies
with the provisions of Section 412.6 and is surrounded and
adjoined by public ways or yards not less in width than one
and one-half times the building height.
The area of a Group E building
no more than one story above grade plane, of Type II, IIIA or
IV construction, shall not be limited provided all of the following
criteria are met:
- 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 1022.
- The building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
- The building is surrounded and adjoined by public ways or yards not less than 60 feet (18288 mm) in width.
In buildings of Type II construction,
the area of a motion picture theater located on the
first story above grade plane shall not be limited where 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 (18288 mm) in width.
The area of covered and open mall buildings and
anchor buildings not exceeding three stories in height that
comply with Section 402 shall not be limited.
Each portion of a building shall be individually
classified in accordance with Section 302.1. Where a
building contains more than one occupancy group, the building
or portion thereof shall comply with the applicable provisions
of Section 508.2, 508.3 or 508.4, or a combination of
these sections.
Exceptions:
- Occupancies separated in accordance with Section 510.
- Where required by Table 415.6.2, areas of Group H- 1, H-2 and H-3 occupancies shall be located in a detached building or structure.
- Uses within live/work units, complying with Section 419, are not considered separate occupancies.
Accessory occupancies
shall be individually classified in accordance with
Section 302.1. The requirements of this code shall apply to
each portion of the building based on the occupancy classification
of that space.
The allowable height
and number of stories of the building containing accessory
occupancies shall be in accordance with Section 504 for
the main occupancy of the building.
The allowable area of
the building shall be based on the applicable provisions of
Section 506 for the main occupancy of the building.
Aggregate accessory occupancies shall not occupy more
than 10 percent of the floor area of the story in which they
are located and shall not exceed the tabular values for nonsprinklered
buildings in Table 506.2 for each such accessory
occupancy.
No separation is
required between accessory occupancies and the main
occupancy.
Exceptions:
- Group H-2, H-3, H-4 and H-5 occupancies shall be separated from all other occupancies in accordance with Section 508.4.
- Group I-1, R-1, R-2 and R-3 dwelling units and sleeping units shall be separated from other dwelling or sleeping units and from accessory occupancies contiguous to them in accordance with the requirements of Section 420.
Buildings or portions of
buildings that comply with the provisions of this section shall
be considered as nonseparated occupancies.
Nonseparated occupancies
shall be individually classified in accordance with
Section 302.1. The requirements of this code shall apply
to each portion of the building based on the occupancy
classification of that space. In addition, the most restrictive
provisions of Chapter 9 that apply to the nonseparated
occupancies shall apply to the total nonseparated occupancy
area. Where nonseparated occupancies occur in a
high-rise building, the most restrictive requirements of
Section 403 that apply to the nonseparated occupancies
shall apply throughout the high-rise building.
The allowable
building area and height of the building or portion
thereof shall be based on the most restrictive allowances
for the occupancy groups under consideration for the type
of construction of the building in accordance with Section
503.1.
No separation is required between
nonseparated occupancies.
Exceptions:
- Group H-2, H-3, H-4 and H-5 occupancies shall be separated from all other occupancies in accordance with Section 508.4.
- Group I-1, R-1, R-2 and R-3 dwelling units and sleeping units shall be separated from other dwelling or sleeping units and from other occupancies contiguous to them in accordance with the requirements of Section 420.
Buildings or portions of
buildings that comply with the provisions of this section shall
be considered as separated occupancies.
Separated occupancies
shall be individually classified in accordance with Section
302.1. Each separated space shall comply with this code
based on the occupancy classification of that portion of the
building.
In each story, the building
area shall be such that the sum of the ratios of the
actual building area of each separated occupancy divided
by the allowable building area of each separated occupancy
shall not exceed 1.
Each separated occupancy
shall comply with the building height limitations based on
the type of construction of the building in accordance with
Section 503.1.
Exception: Special provisions of Section 510 shall permit
occupancies at building heights other than provided
in Section 503.1.
Individual occupancies shall be separated
from adjacent occupancies in accordance with Table
508.4.
Required separations shall be
fire barriers constructed in accordance with Section
707 or horizantal assemblies constructed in accordance
with Section 711, or both, so as to completely separate
adjacent occupancies.
Incidental uses located within single occupancy
or mixed occupancy buildings shall comply with the
provisions of this section. Incidental uses are ancillary functions
associated with a given occupancy that generally pose a
greater level of risk to that occupancy and are limited to those
uses listed in Table 509.
For SI: 1 square foot = 0.0929 m2, 1 pound per square inch (psi) = 6.9 kPa, 1 British thermal unit (Btu) per hour = 0.293 watts,
1 horsepower = 746 watts, 1 gallon = 3.785 L, 1 cubic foot = 0.0283 m3.
Exception: Incidental uses within and serving a dwelling unit are not required to comply with this section.
| ROOM OR AREA | SEPARATION AND/OR PROTECTION |
| Furnace room where any piece of equipment is over 400,000 Btu per hour input | 1 hour or provide automatic sprinkler system |
| Rooms with boilers where the largest piece of equipment is over 15 psi and 10 horsepower | 1 hour or provide automatic sprinkler system |
| Refrigerant machinery room | 1 hour or provide automatic sprinkler system |
| Hydrogen fuel gas rooms, not classified as Group H | 1 hour in Group B, F, M, S and U occupancies; 2 hours in Group A, E, l and R occupancies. |
| Incinerator rooms | 2 hours and provide automatic sprinkler system |
| Paint shops, not classified as Group H, located in occupancies other than Group F | 2 hours; or 1 hour and provide automatic sprinkler system |
| In Group E occupancies, laboratories and vocational shops not classified as Group H | 1 hour or provide automatic sprinkler system |
| In Group I-2 occupancies, laboratories not classified as Group H | 1 hour and provide automatic sprinkler system |
| In ambulatory care facilities, laboratories not classified as Group H | 1 hour or provide automatic sprinkler system |
| Laundry rooms over 100 square feet | 1 hour or provide automatic sprinkler system |
| In Group I-2, laundry rooms over 100 square feet | 1 hour |
| Group I-3 cells and Group I-2 patient rooms equipped with padded surfaces | 1 hour |
| In Group I-2, physical plant maintenance shops | 1 hour |
| In ambulatory care facilities or Group I-2 occupancies, waste and linen collection rooms with containers that have an aggregate volume of 10 cubic feet or greater |
1 hour |
| In other than ambulatory care facilities and Group I-2 occupancies, waste and linen collection rooms over 100 square feet |
I hour or provide automatic sprinkler system |
| In ambulatory care facilities or Group I-2 occupancies, storage rooms greater than 100 square feet | 1 hour |
| Stationary storage battery systems having a liquid electrolyte capacity of more than 50 gallons for flooded lead-acid, nickel cadmium or VRLA, or more than 1,000 pounds for lithium-ion and lithium metal polymer used for facility standby power, emergency power or uninterruptable power supplies |
1 hour in Group B, F, M, S and U occupancies; 2 hours in Group A, E, I and R occupancies. |
Incidental uses shall not be
individually classified in accordance with Section 302.1.
Incidental uses shall be included in the building occupancies
within which they are located.
Incidental uses shall not occupy
more than 10 percent of the building area of the story in
which they are located.
The incidental uses listed
in Table 509 shall be separated from the remainder of the
building or equipped with an automatic sprinkler system, or
both, in accordance with the provisions of that table.
Where Table 509 specifies a fireresistance-
rated separation, the incidental uses shall be
separated from the remainder of the building by a fire barrier
constructed in accordance with Section 707 or a horizantal
assembly constructed in accordance with Section
711, or both. Construction supporting I-hour fire barriers
or horizontal assemblies used for incidental use separations
in buildings of Type IIB, IIIB and VB construction is
not required to be fire-resistance rated unless required by
other sections of this code.
Where Table 509 permits an automatic
sprinkler system without a fire barrier, the incidental
uses shall be separated from the remainder of the
building by construction capable of resisting the passage
of smoke. The walls shall extend from the top of the foundation
or floor assembly below to the underside of the
ceiling that is a component of a fire-resistance-rated floor
assembly or roof assembly above or to the underside of the
floor or roof sheathing, deck or slab above. Doors shall be
self- or automatic-closing upon detection of smoke in
accordance with Section 716.5.9.3. Doors shall not have
air transfer openings and shall not be undercut in excess of
the clearance permitted in accordance with NFPA 80.
Walls surrounding the incidental use shall not have air
transfer openings unless provided with smoke dampers in
accordance with Section 710.8.
Storage rooms in consumer fireworks
(1.4G) facilities used for the retail sale of consumer
fireworks shall be designed and constructed in accordance
with the code for the manufacture, transportation,
storage, and retail sales of fireworks and
pyrotechnic articles, NFP A 1124, as referenced by the
Michigan fireworks safety act, 2011 PA 256, MCL
28.451 to 28.471.
R408.30441
R408.30441
The provisions in Sections 510.2 through
510.9 shall permit the use of special conditions that are
exempt from, or modify, the specific requirements of this
chapter regarding the allowable building heights and areas of
buildings based on the occupancy classification and type of
construction, provided the special condition complies with
the provisions specified in this section for such condition and
other applicable requirements of this code. The provisions of
Sections 510.2 through 510.8 are to be considered independent
and separate from each other.
A building
shall be considered as separate and distinct buildings for
the purpose of determining area limitations, continuity of fire
walls, limitation of number of stories and type of construction
where all of the following conditions are met:
- The buildings are separated with a horizantal assembly having a fire-resistance rating of not less than 3 hours.
- The building below the horizontal assembly is of Type IA construction.
- Shaft, stairway, ramp and escalator enclosures through
the horizantal assembly shall have not less than a 2-
hour fire-resistance rating with opening protectives in
accordance with Section 716.5.
Exception: Where the enclosure walls below the horizontal assembly have not less than a 3-hour fireresistance rating with opening protectives in accordance with Section 716.5, the enclosure walls extending above the horizontal assembly shall be permitted to have a I-hour fire -resistance rating, provided:
- The building above the horizontal assembly is not required to be of Type I construction;
- The enclosure connects fewer than four stories; and
- The enclosure opening protectives above the horizontal assembly have a fire protection rating of not less than 1 hour.
- The building or buildings above the horizontal assembly shall be permitted to have multiple Group A occupancy uses, each with an occupant load of less 300, or Group B, M, R or S occupancies.
- The building below the horioantal assembly shall be protected throughout by an approved automatic sprinkler system in accordance with Section 903.3.1.1, and shall be permitted to be any occupancy allowed by this code except Group H.
- The maximum building height in feet (mm) shall not exceed the limits set forth in Section 504.3 for the building having the smaller allowable height as measured from the grade plane.
A Group S-2 enclosed parking
garage with not more than one story above grade plane and
located below a Group S-2 open parking garage shall be classified
as a separate and distinct building for the purpose of
determining the type of construction where all of the following
conditions are met:
- The allowable area of the building shall be such that the sum of the ratios of the actual area divided by the allowable area for each separate occupancy shall not exceed 1.
- The Group S-2 enclosed parking garage is of Type I or II construction and is at least equal to the fire-resistance requirements of the Group S-2 open parking garage.
- The height and the number of tiers of the Group S-2 open parking garage shall be limited as specified in Table 406.5.4.
- The floor assembly separating the Group S-2 enclosed parking garage and Group S-2 open parking garage shall be protected as required for the floor assembly of the Group S-2 enclosed parking garage. Openings between the Group S-2 enclosed parking garage and Group S-2 open parking garage, except exit openings, shall not be required to be protected.
- The Group S-2 enclosed parking garage is used exclusively for the parking or storage of private motor vehicles, but shall be permitted to contain an office, waiting room and toilet room having a total area of not more than 1,000 square feet (93 m2) and mechanical equipment rooms incidental to the operation of the building.
Where a maximum one
story above grade plane Group S-2 parking garage, enclosed
or open, or combination thereof, of Type I construction or
open of Type IV construction, with grade entrance, is provided
under a building of Group R, the number of stories to
be used in determining the minimum type of construction
shall be measured from the floor above such a parking area.
The floor assembly between the parking garage and the
Group R above shall comply with the type of construction
required for the parking garage and shall also provide a fire resistance
rating not less than the mixed occupancy separation
required in Section 508.4.
The height limitation for buildings of Type IIIA
construction in Groups R-1 and R-2 shall be increased to six
stories and 75 feet (22860 mm) where the first floor assembly
above the basement has a fire-resistance rating of not less
than 3 hours and the floor area is subdivided by 2-hour fireresistance
-rated fire walls into areas of not more than 3,000
square feet (279 m2).
The height limitation for buildings of Type IIA construction
in Groups R-1 and R-2 shall be increased to nine
stories and 100 feet (30480 mm) where the building is separated
by not less than 50 feet (15240 mm) from any other
building on the lot and from lot lines, the exits are segregated
in an area enclosed by a 2-hour fire-resistance-rated fire wall
and the first floor assembly has a fire- resistance rating of not
less than 11⁄2 hours.
Open parking garages constructed under Groups A, I,
B, M and R shall not exceed the height and area limitations
permitted under Section 406.5. The height and area of the
portion of the building above the open parking garage shall
not exceed the limitations in Section 503 for the upper occupancy.
The height, in both feet and stories, of the portion of
the building above the open parking garage shall be measured
from grade plane and shall include both the open parking
garage and the portion of the building above the parking
garage.
Fire barriers constructed in
accordance with Section 707 or horizontal assemblies constructed
in accordance with Section 711 between the parking
occupancy and the upper occupancy shall correspond
to the required fire-resistance rating prescribed in Table
508.4 for the uses involved. The type of construction shall
apply to each occupancy individually, except that structural
members, including main bracing within the open
parking structure, which is necessary to support the upper
occupancy, shall be protected with the more restrictive
fire-resistance-rated assemblies of the groups involved as
shown in Table 601. Means of egress for the upper occupancy
shall conform to Chapter 10 and shall be separated
from the parking occupancy by fire barriers having not
less than a 2-hour fire-resistance rating as required by
Section 707 with self-closing doors complying with Section
716 or horizontal assemblies having not less than a 2-
hour fire-resistance rating as required by Section 711,
with self-closing doors complying with Section 716.
Means of egress from the open parking garage shall comply
with Section 406.5.
Group B or M occupancies located below
a Group S-2 open parking garage of a lesser type of construction
shall be considered as a separate and distinct building
from the Group S-2 open parking garage for the purpose of
determining the type of construction where all of the following
conditions are met:
- The buildings are separated with a horizontal assembly having a fire-resistance rating of not less than 2 hours.
- The occupancies in the building below the horizontal assembly are limited to Groups B and M.
- The occupancy above the horizontal assembly is limited to a Group S-2 open parking garage.
- The building below the horizontal assembly is of Type
IA construction.
Exception:
The building below the horizontal assembly shall be permitted to be of Type IB or II construction, but not less than the type of construction required for the Group S-2 open parking garage above, where the building below is not greater than one story in height above grade plane. - The height and area of the building below the horizontal assembly does not exceed the limits set forth in Section 503.
- The height and area of the Group S-2 open parking garage does not exceed the limits set forth in Section 406.5. The height, in both feet and stories, of the Group S-2 open parking garage shall be measured from grade plane and shall include the building below the horizontal assembly.
- Exits serving the Group S-2 open parking garage discharge directly to a street or public way and are separated from the building below the horizontal assembly by 2-hour fire barriers constructed in accordance with Section 707 or 2-hour horizontal assemblies constructed in accordance with Section 711, or both.
Where two or more buildings are provided above the horizontal
assembly separating a Group S-2 parking garage or building
below from the buildings above in accordance with the
special provisions in Section 510.2, 510.3 or 510.8, the buildings
above the horizontal assembly shall be regarded as separate
and distinct buildings from each other and shall comply
with all other provisions of this code as applicable to each
separate and distinct building.