IBC Design 721.1(1) 1-3.2
4-Hour Fire Rated Steel columns and all of primary trusses — 2" hollow clay tile; 3/4" mortar between tile and column…
IBC Table 721.1(1), Item 1-3.2 (Steel columns and all of primary trusses): protection by 2" hollow clay tile; 3/4" mortar between tile and column; 3/8" metal mesh 0.046" wire diameter in horizontal joints; limestone concrete fill; plastered with 3/4" gypsum plaster. Minimum insulating material thickness — 4-hr: 3". Prescriptive protection from the adopted building code — see table footnotes for conditions.
2" hollow clay tile; 3/4" mortar between tile and column; 3/8" metal mesh 0.046" wire diameter in horizontal joints; limestone concrete fill; plastered with 3/4" gypsum plaster.
The full text is for BuildSpec members
Read the complete section, search across every adopted code, run the calculators and ask Copilot — free for 14 days, no card required.
- Layer-by-layer components with thicknesses
- Cross-section diagram
- Applicable code sections and test standard
- 6 related assemblies