IBC Design 721.1(1) 1-5.1
4-Hour Fire Rated Steel columns and all of primary trusses — Vermiculite concrete, 1:4 mix by volume over paper-backed…
IBC Table 721.1(1), Item 1-5.1 (Steel columns and all of primary trusses): protection by Vermiculite concrete, 1:4 mix by volume over paper-backed wire fabric lath wrapped directly around column with additional 2" x 2" 0.065"/0.065" (No. 16/16 B.W. gage) wire fabric placed 3/4" from outer concrete surface. Wire fabric tied with 0.049" (No. 18 B.W. gage) wire spaced 6" on center for inner layer and 2" on center for outer layer. Minimum insulating material thickness — 4-hr: 2". Prescriptive protection from the adopted building code — see table footnotes for conditions.
Vermiculite concrete, 1:4 mix by volume over paper-backed wire fabric lath wrapped directly around column with additional 2" x 2" 0.065"/0.065" (No. 16/16 B.W. gage) wire fabric placed 3/4" from outer concrete surface. Wire fabric tied with 0.049" (No. 18 B.W. gage) wire spaced 6" on center for…
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- Layer-by-layer components with thicknesses
- Cross-section diagram
- Applicable code sections and test standard
- 6 related assemblies