IBC Design 721.1(2) 3-1.4

4-Hour Fire Rated Concrete masonry units — Calcareous or siliceous gravel.

IBC Table 721.1(2), Item 3-1.4 (f, g) (Concrete masonry units): Calcareous or siliceous gravel. Minimum finished thickness (face-to-face) — 4-hr: 6.2" · 3-hr: 5.3" · 2-hr: 4.2" · 1-hr: 2.8". Prescriptive assembly from the adopted building code — thicknesses are code minimums, see table footnotes for conditions.

Calcareous or siliceous gravel.

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  • Layer-by-layer components with thicknesses
  • Cross-section diagram
  • Applicable code sections and test standard
  • 6 related assemblies
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