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	
Structural framea
Including columns, girders, trusses	3b,g	2b	1	0	1	0	HT	1	0	
Bearing walls
  Exteriorf
  Interior	
43
43b	
32
32b	
1
1	
0
0	
2
1	
2
0	
2
2b1/HT	
1
1	
0
0	
Nonbearing walls and partitions   
  Exterior
  Interiore		See Table 602
See Section 602		
Floor construction
Including supporting beams and joists	3g2	2	1d	0d	1d	0d	HT	1	0	
Roof construction 
Including supporting beams and joists	1 ½ c, g	1c	1c	0c	1c	0	HT	1c	0	

For SI:	1 foot = 304.8 mm.

a. The structural frame shall be considered to be the columns and the girders, beams, trusses and spandrels having direct connections to the columns and bracing members designed to carry gravity loads. The members of floor or roof panels which have no connection to the columns shall be considered secondary members and not a part of the structural frame.
b. Roof supports: Fire- resistance ratings of the structural frame and bearing walls are permitted to be reduced by 1 hour where supporting a one floor or one roof only.
c. 1. Except in Factory-Industrial (F-1), Hazardous (H), Institutional (I), Mercantile (M), and Moderate Storage (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.
2. In all occupancies, heavy timber shall be allowed where a 1 hour or less fire resistance rating is required.
23. In Type I and Type II construction, fire-retardant-treated wood shall be allowed in buildings not over two stories including girders and trusses as part of the roof construction.
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.
d. Group B and M occupancies of Type II or III construction five or more stories in height shall be required to have a minimum 2-hour fire resistance rating for the floor construction located over the basement.
e. For interior nonbearing partitions in Type IV construction, also see Section 602.4.6.
f. Not less than the fire-resistance rating based on fire separation distance (see Table 602.)
g. For Group A, B, E, F and R occupancies and parking garages, the required fire-resistance ratings for the structural frame, floor and roof construction, including supporting beams and joists, shall be permitted to be reduced by 1-hour where the building is protected throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1, but the fire resistance rating shall not be less than 1-hour.

h. For unsprinklered Group E occupancies of Type, II-B, III-B, IV or V-B construction, the floor construction located immediately above useable space in basements shall have a fire-resistance rating of not less than 1-hour.

TABLE 602
FIRE-RESISTANCE RATING REQUIREMENTS FOR EXTERIOR WALLS BASED ON FIRE SEPARATION DISTANCEa
FIRE SEPARATION DISTANCE (feet)	TYPE OF CONSTRUCTION	GROUP
H	GROUP F-1, M, S-1	GROUP A,B,E,F-2,       I, Rb, S-2, U	
< 5c	I-A, I-B, III-A, III-B, IV
Others All	3
3	3
2	3
1	
> 5
< 10	I-A, I-B, III-A, III-B, IV
Others	3
2	2
1	21
1	
> 10
< 3020	I-A, I-B, III-A, III-B, IV
II-B, V-B
Others	2
1
1	21
0
1	21
0
1	
> 20
<30	I-A, I-B, III-A, III-B, IV
Others	1
1	1
0	1
0	
>30	All	0	0	0	

For SI:	1 foot = 304.8 mm

a. Load-bearing exterior walls shall comply with the fire-resistance rating requirements of Table 601.
b. Group R-3 and Group U when used as accessory to Group R-3, as applicable in Section 101.2 shall not be required to have a fire-resistance rating where fire separation distance is 3 feet or more.
c. See Section 503.2 for party walls.