Code of Massachusetts Regulations
780 CMR - STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
Chapter 5 - General Building Heights and Areas
Section 508 - MIXED USE AND OCCUPANCY
Subsection 508.4 - Separated occupancies
Current through Register 1531, September 27, 2024
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 | Ad, E | I-1, I-3, I-4 | I-2 | R | F-2, S-2b, U | B, 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 | |
A d, E | N | N | 1 | 2 | 2 | NP | 1 | 2 | N | 1 | 1 | 2 | NP | NP | 3 | 4 | 2 | 3 a |
I-1, I-3, I-4 | - | - | N | N | 2 | NP | 1 | NP | 1 | 2 | 1 | 2 | NP | NP | 3 | NP | 2 | NP |
I-2 | - | - | - | - | N | N | 2 | NP | 2 | NP | 2 | NP | NP | NP | 3 | NP | 2 | NP |
R | - | - | - | - | - | - | N | N | 1 c | 2 c | 1 | 2 | NP | NP | 3 | NP | 2 | NP |
F-2, S-2b, U | - | - | - | - | - | - | - | - | N | N | 1 | 2 | NP | NP | 3 | 4 | 2 | 3 a |
B, F-1, M, S-1 | - | - | - | - | - | - | - | - | - | - | N | N | NP | NP | 2 | 3 | 1 | 2 a |
H-1 | - | - | - | - | - | - | - | - | - | - | - | - | N | NP | NP | NP | NP | NP |
H-2 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | N | NP | 1 | NP |
H-3, H-4, H-5 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 1 e, f | 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. For Group H-5 occupancies, see Section 903.2.5.2. 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 406.1.4. d. Commercial kitchens need not be separated from the restaurant seating areas that they serve. e. Separation is not required between occupancies of the same classification. f. For H-5 occupancies, see Section 415.8.2.2. |
508.4.1 Occupancy classification. 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 buildingarea 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 permitted by Section 509.
508.4.4 Separation. Individual occupancies shall be separated from adjacent occupancies in accordance with Table 508.4.