by Jerry Peck - Codeman on Mon Apr 12, 2010 5:32 pm
Hi Marc,
What you are referring to are "Fire Partitions" instead of "Fire Walls", with Fire Partitions being under Section 708. Fire partitions have a minimum required fire-resistance rating of not less than 1 hour, with exceptions allowed to 1/2 hour with automatic sprinkler systems meeting certain requirements.
From the 2006 IBC: (underlining and bold are mine)
- SECTION 708
- - FIRE PARTITIONS
- - - 708.1 General. The following wall assemblies shall comply with this section:
- - - - 1. Walls separating dwelling units in the same building.
- - - - 2. Walls separating sleeping units in occupancies in Group R-1 hotel, R-2 and I-1 occupancies.
- - - - 3. Walls separating tenant spaces in covered mall buildings as required by Section 402.7.2.
- - - - 4. Corridor walls as required by Section 1017.1.
- - - - 5. Elevator lobby separation as required by Section 707.14.1.
- - - - 6. Residential aircraft hangars.
- - - 708.2 Materials. The walls shall be of materials permitted by the building type of construction.
- - - 708.3 Fire-resistance rating. Fire partitions shall have a fire-resistance rating of not less than 1 hour.
- - - - Exceptions:
- - - - - 1. Corridor walls as permitted by Table 1017.1. (Jerry's note: This section allows the walls between the corridor and the dwelling unit to be 0.5 hours R occupancies with a sprinkler system meeting certain requirements.)
- - - - - 2. Dwelling and sleeping unit separations in buildings of Type IIB, IIIB and VB construction shall have fire-resistance ratings of not less than 1/2 hour in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
Keep in mind, though, that a 1/2 hour fire-resistance rated wall is constructed the same as a 1 hour fire-resistance rated wall.
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired