IBC Design 721.1(2) 3-1.3

4-Hour Fire Rated Concrete masonry units — Limestone, cinders or air-cooled slag.

IBC Table 721.1(2), Item 3-1.3 (f) (Concrete masonry units): Limestone, cinders or air-cooled slag. Minimum finished thickness (face-to-face) — 4-hr: 5.9" · 3-hr: 5.0" · 2-hr: 4.0" · 1-hr: 2.7". Prescriptive assembly from the adopted building code — thicknesses are code minimums, see table footnotes for conditions.

Limestone, cinders or air-cooled slag.

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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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