This appear to be a one hour construction through out with sprinklers to
allow four story wood framed construction. One thing you may point out,
that the UBC interpretive manual allows the use of solid lumber in joints
at wall and floor intersections to specifically deal with the integrity of
the joint. A one hour joint can be constructed from a 3- 2x solid block
and a two hour joint can be constructed out of 4-2x solid block at the
joint. The Building will be required to have a one hour floor ceiling
assembly and there by having the required protection within the fire
envoelope. I hope this help. If I read the building official concerns
correctly, this will solve the problem. then a ledger attachment should not
be an issue when the joint is compsed of solid lumber to provide equivalent
fire protection. Hope this help.
Samir Y. Ghosn, P.E.
Harris & Associates
At 09:20 PM 12/27/2000 -0600, you wrote:
>For a 4-story, wood-framed, senior housing facility, the building official
>requires that the stairways be sheathed with gypboard on the outside, one
>layer of 5/8", and the gypboard cannot be interrupted by ledgers. Neither
>will he allow the floor joists to bear on the stairway walls.
>Studs are 2x6, D.Fir-Larch(N), @ 16". Load from each floor is about 1100
>Can a ledger be lag-screwed or thru-bolted through the gypboard? What I
>have in mind is a single 2x12, D.Fir-Larch(N) with the floor joists attached
>with Simpson hangers.
>Are the values in UBC Table 23-III-B-1 applicable? Modifiable?
>Is there a better way to approach the problem?
>John P. Riley, PE, SE
>20 Oakwood Drive, Blue Grass, Iowa 52726
>Tel & Fax: 319-381-3949