I am having trouble determining which firestopping detail is appropriate for my 4" steel conduit penetration through a concrete floor. The floor is 5" thick and I am having trouble decide between details C-AJ-1291 and C-BJ-1046.
C-AJ-1291 notes that the detail can be used concrete floors greater than 2.5" thick. Is there a maximum floor thickness allowed for this detail? Similar question for C-BJ-1046, no maximum floor depth is listed for the detail.
This is a common area I am having trouble with when looking for the appropriate details for concrete penetrations. I am unsure if the details I am selecting are correct as there are no maximum depths listed.
Daniel,
If there is no maximum specified on the detail, then Hilti is not limiting the maximum assembly thickness. Majority of our systems do not specify a maximum assembly thickness, as the only time a maximum thickness would come into play would be with a preformed device that runs within the assembly (such as our CFS-DID devices, for example). For sealant or mineral wool/sealant solutions, the minimum assembly thickness would be the critical dimension. In summary, if the maximum assembly thickness is not specified, then the maximum thickness is not relevant so you only need to worry about meeting that minimum dimension.
With that being said, C-BJ-1046 is designed for a minimum 8" thick hollow-core floor, so this system would not be appropriate for a 5" thick floor.
Thank you,
Jessica Starks
Senior Fire Protection Engineer