Code of Massachusetts Regulations
780 CMR - STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
Chapter 6 - Types of Construction
Section 601 - GENERAL


Current through Register 1531, September 27, 2024

TABLE 601 FIRE-RESISTANCE RATING REQUIREMENTS FOR BUILDING ELEMENTS (hours)

BUILDING ELEMENT TYPE I TYPE II TYPE III TYPE IV TYPE V
A B Ad B Ad B HT Ad B
Primary structural frameg
(see Section 202)
3a 2a 1 0 1 0 HT 1 0
Bearing Walls
Exteriorf,g 3 2 1 0 2 2 2 1 0
Interior 3a 2a 1 0 1 0 1/HT 1 0
Nonbearing walls and partitions
Exterior
See Table 602
Nonbearing walls and partitions
Interiore
0 0 0 0 0 0 See Section 602.4.6 0 0
Floor construction and secondary
members (see Section 202)
2 2 1 0 1 0 HT 1 0
Roof construction and secondary
members (see Section 202)
11/2b 1b,c 1b,c 0c 1b,c 0 HT 1b,c 0

For SI: 1 foot = 304.8 mm.
a. Roof supports: Fire-resistance ratings of primary structural frame and bearing walls are permitted to be reduced by 1 hour where supporting a roof only.
b. Except in Group F-1, H, M and S-1 occupancies, fire protection of structural members shall not be required, including protection of roof framing and decking where every part of the roof construction is 20 feet or more above any floor immediately below. Fire-retardant-treated wood members shall be allowed to be used for such unprotected members.
c. In all occupancies, heavy timber shall be allowed where a 1-hour or less fire-resistance rating is required.
d. An approved automatic sprinkler system in accordance with Section 903.3.1.1 shall be allowed to be substituted for 1-hour fire-resistance-rated construction, provided such system is not otherwise required by other provisions of the code or used for an allowable area increase in accordance with Section 506.3 or an allowable height increase in accordance with Section 504.2. The 1-hour substitution for the fire resistance of exterior walls shall not be permitted.
e. Not less than the fire-resistance rating required by other sections of this code.
f. Not less than the fire-resistance rating based on fire separation distance (see Table 602).
g. Not less than the fire-resistance rating as referenced in Section 704.10

Disclaimer: These regulations may not be the most recent version. Massachusetts may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.