IBC Design 721.1(1) 1-1.4
4-Hour Fire Rated Steel columns and all of primary trusses — Siliceous aggregate concrete and concrete excluded in Item…
IBC Table 721.1(1), Item 1-1.4 (Steel columns and all of primary trusses): protection by Siliceous aggregate concrete and concrete excluded in Item 1-1.1, members 6" x 6" or greater. Minimum insulating material thickness — 4-hr: 3" · 3-hr: 2" · 2-hr: 1-1/2" · 1-hr: 1". Prescriptive protection from the adopted building code — see table footnotes for conditions.
Siliceous aggregate concrete and concrete excluded in Item 1-1.1, members 6" x 6" or greater.
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- Layer-by-layer components with thicknesses
- Cross-section diagram
- Applicable code sections and test standard
- 6 related assemblies