In the UBC and IBC, there is an "obscure" footnote in the fire-rated wall assembly tables. It simply requires a reduction of allowable fc' stress (multiply by 0.78) for design of load-bearing stud walls if wall is fire-rated. (I don't have access to the Codes now, so I can't give a page or section reference).
My question- does the reduction also apply to the stud at each end of header? If so, what about double or triple studs at ends of headers? Are those considered more fire-resistant being nailed together as a multi-ply "post"?Finally, what about any 4x or 6x post in the wall?
My question- does the reduction also apply to the stud at each end of header? If so, what about double or triple studs at ends of headers? Are those considered more fire-resistant being nailed together as a multi-ply "post"?Finally, what about any 4x or 6x post in the wall?