TABLE 601 FIRE-RESISTANCE RATING REQUIREMENTS FOR BUILDING ELEMENTS (HOURS)
| BUILDING ELEMENT | TYPE I | TYPE II | TYPE III | TYPE IV | TYPE V | ||||
| A | B | A | B | A | B | HT | A | B | |
| Primary structural framef (see Section 202) | 3a | 2a | 1 | 0 | 1 | 0 | HT | 1 | 0 |
| Bearing walls | |||||||||
| Exteriore, f | 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 Interiord | 0 | 0 | 0 | 0 | 0 | 0 | See Section 602.4.6 | 0 | 0 |
| Floor construction and associated secondary members (see Section 202) | 2 | 2 | 1 | 0 | 1 | 0 | HT | 1 | 0 |
| Roof construction and associated 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. Not less than the fire-resistance rating required by other sections of this code. |
| e. Not less than the fire-resistance rating based on fire separation distance (see Table 602). |
| f. Not less than the fire-resistance rating as referenced in Section 704.10. |
The provisions of this chapter shall control the classification of buildings as to type of construction.