N.Y.C. Admin. Code § BC 508: Section BC 508: Mixed Use and Occupancy

508.1 General.

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 Sections 508.2, 508.3 or 508.4, or a combination of these sections.

Exceptions:

1. Occupancies separated in accordance with Section 510.

2. 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.

3. Where identified in Table 509, rooms or spaces shall be treated as incidental uses.

4. Where not identified in Table 509, mechanical and/or electrical equipment rooms shall be permitted to be classified as the occupancy within which they are located, or at the option of the applicant, classified as Group F-2 occupancy in accordance with Section 306.3.

5. Commercial kitchens classified as Group F-2 need not be separated by fire separations from adjoining dining spaces, provided that the conditions of Items 5.1, 5.2, and 5.3 are met:

5.1. The cooking equipment is vented directly to the outdoors;

5.2. A draft curtain of noncombustible material, at least 24 inches (609 mm) down from the ceiling, is provided to separate the opening between the cooking facilities and the dining spaces; and

5.3. A fire protection system is installed and located as set forth in Item 5.3.1 or 5.3.2.

5.3.1. A fire protection system in accordance with Sections 903 and 904 is installed within the cooking facilities. Additionally, sprinkler heads protecting the opening between the cooking facilities and the dining spaces shall be located within 24 inches (609 mm) of the curtain on the cooking facilities side; or

5.3.2. A fire protection system in accordance with Section 903 is located along any opening between the cooking facilities and the dining space on the cooking facilities side, with sprinkler heads located within 24 inches (609 mm) of the opening and, if the opening is more than 60 inches (1524 mm) wide, the sprinkler heads are spaced not more than 48 inches (1219 mm) on center.

Where the conditions of Items 5.1, 5.2, and 5.3 cannot be satisfied, such commercial kitchen shall be separated from adjoining dining spaces in accordance with Table 508.4, footnote f.

508.2 Accessory occupancies.

Accessory occupancies are those occupancies that are ancillary to the main occupancy of the building or portion thereof. Accessory occupancies shall comply with the provisions of Sections 508.2.1 through 508.2.4.

508.2.1 Occupancy classification.

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.

508.2.2 Allowable building height.

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.

508.2.3 Allowable building area.

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 building 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.

Exceptions:

1. The following accessory occupancies are permitted to occupy more than 10 percent of the floor area of the story in which they are located:

1.1. Accessory assembly areas having a floor area less than 750 square feet (69.7 m

2

).

1.2. Assembly areas that are accessory to Group E occupancies.

1.3. Accessory religious educational rooms and religious auditoriums with occupant loads of less than 100.

2. Rooms or spaces within Group H-2, H-3, H-4 or H-5 occupancy shall not be considered accessory occupancies and shall be treated as separated occupancies.

508.2.4 Separation of occupancies.

No separation is required between accessory occupancies and the main occupancy.

Exceptions:

1. Group H-2, H-3, H-4 and H-5 occupancies shall be separated from all other occupancies in accordance with Section 508.4.

2. Separated tenancies in accordance with the requirements of Section 510.10.

508.3 Nonseparated occupancies.

Buildings or portions of buildings that comply with the provisions of this section shall be considered as nonseparated occupancies.

508.3.1 Occupancy classification.

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.

508.3.2 Allowable building area and height.

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.

508.3.3 Separation.

No separation is required between nonseparated occupancies.

Exceptions:

1. Group H-2, H-3, H-4 and B-5 occupancies shall be separated from all other occupancies in accordance with Section 508.4.

2. Separated tenancies in accordance with Section 510.10.

3. Commercial kitchens shall be separated in accordance with Section 508.1, Exception 5.

508.4 Separated occupancies.

Buildings or portions of buildings that comply with the provisions of this section shall be considered as separated occupancies.

Table 508.4 Required Separation of Occupancies (Hours)

Occupancy

A, E

I-1

a

, I-3, I-4

I-2

Ra

F-2, S-2

b

, U

B

c

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

S

NS

S

NS

S

NS

A, E

N

N

1

2

2

NP

1

2

N

f

1

f

1

2

1

2

1

2

1

2

NP

NP

3

4

2

3

2

NP

I-1

a

, I-3, I-4

–

–

N

N

2

NP

1

NP

1

2

1

2

1

2

1

2

1

2

NP

NP

3

NP

2

NP

2

NP

I-2

–

–

–

–

N

N

2

NP

2

NP

2

NP

2

NP

2

NP

2

NP

NP

NP

3

NP

2

NP

2

NP

R

a

–

–

–

–

–

–

N

N

1

c

2

c

1

2

1

2

1

2

1

2

NP

NP

3

NP

2

NP

2

NP

F-2, S-2

b

, U

–

–

–

–

–

–

–

–

N

N

1

2

1

2

1

2

1

2

NP

NP

3

4

2

3

2

NP

B

e

–

–

–

–

–

–

–

–

–

–

N

N

2

3

1

2

2

3

NP

NP

2

3

1

2

1

NP

F-1

–

–

–

–

–

–

–

–

–

–

–

–

N

N

2

3

2

3

NP

NP

2

3

1

2

1

NP

M

–

–

–

–

–

–

–

–

–

–

–

–

–

–

N

N

2

3

NP

NP

2

3

1

2

1

NP

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

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

1

d

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.

a. See Section 420.

b. The required separation from areas used only for private or pleasure vehicles shall be reduced by 1 hour but to not less than 1 hour.

c. See Section 406.3.4.

d. Separation is not required between occupancies of the same classification.

e. See Section 422.2 for ambulatory care facilities.

f. A commercial kitchen in Group F-2 that does not comply with Section 508.1, Exception 5 shall be separated from adjoining dining spaces with 1-hour fire separation where the dining spaces are equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1, and separated with 2-hour fire separation where the dining spaces is not equipped throughout with an automatic sprinkler system.

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.

508.4.2 Allowable building area.

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.

508.4.3 Allowable height.

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.

508.4.4 Separation.

Individual occupancies shall be separated from adjacent occupancies in accordance with Table 508.4.

Exception: Fire separations of Group H and I-2 occupancies shall not be permitted any reductions in fire-resistance ratings.

508.4.4.1 Construction.

Required separations shall be fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 711, or both, so as to completely separate adjacent occupancies.