U.S. State and City Codes
This information was last updated in March 2022
International Building Code
(IBC 2018)
(IBC 2018)
3 Storeys
The US model building code is the International Building Code, which permits a single exit for R-2 residential occupanices up to 3 stories, with a max. of 4 dwelling units per floor. The building must also "be equipped throughout with an automatic sprinkler system."
The US model building code is the International Building Code, which permits a single exit for R-2 residential occupanices up to 3 stories, with a max. of 4 dwelling units per floor. The building must also "be equipped throughout with an automatic sprinkler system."
Seattle
6 Storeys
See Seattle Jurisdiction for more information.
New York City
6 Storeys
1021.2 Single Exits
Only one exit shall be required in buildings or from stories of buildings as described below:
1. Stories in buildings as described in Table 1021.2.
2. Buildings of Group R-3 occupancy.
3. Single-level buildings with the occupied space at the level of exit discharge provided that the story or space complies with Section 1015.1 as a space with one means of egress.
4. Buildings of Group R-2 occupancy where all of the following conditions are met:
5. Buildings of Group R-2 occupancy of construction Type I or II not exceeding six stories and not exceeding 2,000 square feet (186 m2) per story.
935 Pacific Street / Loadingdock5 Architecture
https://www.archdaily.com/20466/935-pacific-street-loadingdock5-architecture
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253 Pacific Street / James Cleary Architecture
https://www.archdaily.com/331062/253-pacific-street-james-cleary-architecture
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Switch Building / nArchitects
https://www.archdaily.com/4484/switch-building-narchitects
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1021.2 Single Exits
Only one exit shall be required in buildings or from stories of buildings as described below:
1. Stories in buildings as described in Table 1021.2.
2. Buildings of Group R-3 occupancy.
3. Single-level buildings with the occupied space at the level of exit discharge provided that the story or space complies with Section 1015.1 as a space with one means of egress.
4. Buildings of Group R-2 occupancy where all of the following conditions are met:
4.1. The building does not exceed four stories;
4.2. The building contains not more than three dwelling units per story;
4.3. The building is of construction Type I or II;
4.4. The building does not exceed 2,500 square feet (232 m2) per story;
4.5. Each dwelling unit has at least one window facing the street, or facing a lawful yard with open, unobstructed, and direct access to the street;
4.6. The stairway extends to the roof surface through a stairway bulkhead complying with Section 1509.2 provided the roof has a slope not steeper than 20 degrees (0.35 rad). In lieu of the stairway bulkhead, the stair may be constructed against the street wall with one window facing the street at every landing and access to the roof is provided via a scuttle with a stationary, noncombustible access ladder;
4.7. The stairway is enclosed in 2-hour fire-rated walls with all exit doors leading into the stairway having at least 11/2 -hour fire rating; and
4.8. The building shall be equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.2.
5. Buildings of Group R-2 occupancy of construction Type I or II not exceeding six stories and not exceeding 2,000 square feet (186 m2) per story.
New York City Examples
935 Pacific Street / Loadingdock5 Architecture
https://www.archdaily.com/20466/935-pacific-street-loadingdock5-architecture
253 Pacific Street / James Cleary Architecture
https://www.archdaily.com/331062/253-pacific-street-james-cleary-architecture
Switch Building / nArchitects
https://www.archdaily.com/4484/switch-building-narchitects
Philadelphia
3 Storeys
1006.3.3 Single Exits
A single exit or access to a single exit shall be permitted from any story or occupied roof where one of the following conditions exists:
1. The occupant load, number of dwelling units and common path of egress travel distance do not exceed the values in Table 1006.3.3(1) or 1006.3.3(2).
2. Rooms, areas and spaces complying with Section 1006.2.1 with exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit or access to a single exit.
3. Parking garages where vehicles are mechanically parked shall be permitted to have one exit or access to a single exit.
4. Group R-3 and R-4 occupancies shall be permitted to have one exit or access to a single exit.
5. Individual single-story or multistory dwelling units shall be permitted to have a single exit or access to a single exit from the dwelling unit provided that both of the following criteria are met:
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XS House / ISA
https://www.archdaily.com/931740/xs-house-isa
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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 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).
505.2.1 Area Limitation
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.
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 be not greater than two-thirds of the floor area of the room.
2. 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.
3. The aggregate area of a mezzanine within a dwelling unit that is located in a building equipped throughout with an approved 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:
El Chalet / ISA
https://www.archdaily.com/801736/el-chalet-isa
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1006.3.3 Single Exits
A single exit or access to a single exit shall be permitted from any story or occupied roof where one of the following conditions exists:
1. The occupant load, number of dwelling units and common path of egress travel distance do not exceed the values in Table 1006.3.3(1) or 1006.3.3(2).
2. Rooms, areas and spaces complying with Section 1006.2.1 with exits that discharge directly to the exterior at the level of exit discharge, are permitted to have one exit or access to a single exit.
3. Parking garages where vehicles are mechanically parked shall be permitted to have one exit or access to a single exit.
4. Group R-3 and R-4 occupancies shall be permitted to have one exit or access to a single exit.
5. Individual single-story or multistory dwelling units shall be permitted to have a single exit or access to a single exit from the dwelling unit provided that both of the following criteria are met:
5.1. The dwelling unit complies with Section 1006.2.1 as a space with one means of egress.
5.2. Either the exit from the dwelling unit discharges directly to the exterior at the level of exit discharge, or the exit access outside the dwelling unit's entrance door provides access to not less than two approved independent exits.
Philadelphia Examples
XS House / ISA
https://www.archdaily.com/931740/xs-house-isa
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 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).
505.2.1 Area Limitation
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.
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 be not greater than two-thirds of the floor area of the room.
2. 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.
3. The aggregate area of a mezzanine within a dwelling unit that is located in a building equipped throughout with an approved 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:
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 42 inches (1067 mm) in height, columns and posts; and
3.3. Exceptions to Section 505.2.3 shall not be permitted.
El Chalet / ISA
https://www.archdaily.com/801736/el-chalet-isa
Puerto Rico
4 stories
Boston
.
Chicago
Louisville