IBC 2009, Section 1022, requires exit enclosures to be constructed as Fire Barriers per Section 707. Section 707.5, Continuity, requires the fire barriers to extend from the top of the floor/ceiling assembly below to the underside of the floor or roof sheathing above.
I have a three story apartment building (R-2) of VB construction, framed walls and wood trusses. I am requiring the exit enclosure (interior) to extend to the roof sheathing as required by 707.5. My reasoning is that if the exit enclosure were allowed to terminate at a top enclosure at the bottom of the trusses, the exit enclosure section would have sent you to Section 708 for shaft construction instead of 707 for fire barrier construction. Both sections contain the same requirements for openings, penetrations, joints, ducts, etc. except the shaft is permitted to terminate at a top enclosure and the exit enclosure does not.
What is your interp of this section? If you allow an exit enclosure to terminate at a rated top enclosure, how do you make the jump from section 707 to 708?
I have a three story apartment building (R-2) of VB construction, framed walls and wood trusses. I am requiring the exit enclosure (interior) to extend to the roof sheathing as required by 707.5. My reasoning is that if the exit enclosure were allowed to terminate at a top enclosure at the bottom of the trusses, the exit enclosure section would have sent you to Section 708 for shaft construction instead of 707 for fire barrier construction. Both sections contain the same requirements for openings, penetrations, joints, ducts, etc. except the shaft is permitted to terminate at a top enclosure and the exit enclosure does not.
What is your interp of this section? If you allow an exit enclosure to terminate at a rated top enclosure, how do you make the jump from section 707 to 708?