Glennman CBO
Silver Member
- Joined
- Oct 20, 2009
- Messages
- 441
2006 IBC, section 706, VB construction.
I've seen two different methods of construction of shafts that continue through floors.
One is where the fire barrier wall above the penetrated floor is setting on top of the floor in a platform frame fashion. The drywall inside the shaft is continuous where it passes through the floor, and the drywall on the outside of the shaft stops at the intersecting ceiling, and starts again above the floor. The rim of the floor is solidly blocked, but there is no drywall in the concealed space (this is not a suspended ceiling, it is a hard lid). I've also seen this method where they have installed drywall between the intersecting perpendicular joists, or, they would install drywall at the "rim" joist.
The other method I've seen is where the shaft wall is framed in a balloon frame method, and the drywall is continuous through the floor on both sides (inside and outside the shaft) and there is a "hollow vertical space" at the floor line that is fireblocked. The floor is setting on its own independent wall in a platform fashion, and does not intersect into the shaft wall. There are then (2) walls, one makes up the shaft, and the other makes up the parallel wall supporting the floor. The space between the (2) walls is fireblocked at the top.
Which method, or methods, meets the requirements for continuity, as well as meeting the requirement of rating the supporting construction? (I hope I described all this OK).
I've seen two different methods of construction of shafts that continue through floors.
One is where the fire barrier wall above the penetrated floor is setting on top of the floor in a platform frame fashion. The drywall inside the shaft is continuous where it passes through the floor, and the drywall on the outside of the shaft stops at the intersecting ceiling, and starts again above the floor. The rim of the floor is solidly blocked, but there is no drywall in the concealed space (this is not a suspended ceiling, it is a hard lid). I've also seen this method where they have installed drywall between the intersecting perpendicular joists, or, they would install drywall at the "rim" joist.
The other method I've seen is where the shaft wall is framed in a balloon frame method, and the drywall is continuous through the floor on both sides (inside and outside the shaft) and there is a "hollow vertical space" at the floor line that is fireblocked. The floor is setting on its own independent wall in a platform fashion, and does not intersect into the shaft wall. There are then (2) walls, one makes up the shaft, and the other makes up the parallel wall supporting the floor. The space between the (2) walls is fireblocked at the top.
Which method, or methods, meets the requirements for continuity, as well as meeting the requirement of rating the supporting construction? (I hope I described all this OK).
