IBC Design 721.1(1) 1-6.3
4-Hour Fire Rated Steel columns and all of primary trusses — Perlite or vermiculite gypsum plaster on metal lath…
IBC Table 721.1(1), Item 1-6.3 (Steel columns and all of primary trusses): protection by Perlite or vermiculite gypsum plaster on metal lath applied to 3/4" cold-rolled channels spaced 24" apart vertically and wrapped flatwise around column. Minimum insulating material thickness — 4-hr: 1-1/2". Prescriptive protection from the adopted building code — see table footnotes for conditions.
Perlite or vermiculite gypsum plaster on metal lath applied to 3/4" cold-rolled channels spaced 24" apart vertically and wrapped flatwise around column.
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