IBC Design 721.1(1) 1-7.1
2-Hour Fire Rated Steel columns and all of primary trusses — Multiple layers of 1/2" gypsum wallboard. Wallboard…
IBC Table 721.1(1), Item 1-7.1 (Steel columns and all of primary trusses): protection by Multiple layers of 1/2" gypsum wallboard. Wallboard applied without horizontal joints. Corner edges of each layer staggered. Wallboard layer below outer layer secured to column with doubled 0.049" (No. 18 B.W. gage) steel wire ties spaced 15" on center. Exposed corners taped and treated. Minimum insulating material thickness — 2-hr: 2" · 1-hr: 1". Prescriptive protection from the adopted building code — see table footnotes for conditions.
Multiple layers of 1/2" gypsum wallboard. Wallboard applied without horizontal joints. Corner edges of each layer staggered. Wallboard layer below outer layer secured to column with doubled 0.049" (No. 18 B.W. gage) steel wire ties spaced 15" on center. Exposed corners taped and treated.
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- Layer-by-layer components with thicknesses
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- Applicable code sections and test standard
- 6 related assemblies