UL Design G512
3-Hour Fire Rated G512 assembly
UL Design G512 — Three-hour steel joist floor-ceiling (restrained assembly, unrestrained assembly, and unrestrained beam ratings all 3 hr). A 2-1/2 in. normal-weight concrete slab (carbonate or siliceous aggregate, 150 pcf, 4500 psi) reinforced with 6x6-W1.4xW1.4 welded wire fabric is cast on a 3/8 in. rib, 3.4 lb/sq yd expanded steel form (corrugated steel deck alternate) supported on Type 12J2 min steel joists spaced 24 in. o.c. welded to end supports, with a W8x35 min beam and 1/2 in. diameter continuous bar bridging. The ceiling is one layer of 5/8 in. Type C gypsum board fastened 12 in. o.c. to min 25 gauge hat-shaped furring channels spaced 24 in. o.c. STC 53 per National Gypsum listing.
Three-hour steel joist floor-ceiling (restrained assembly, unrestrained assembly, and unrestrained beam ratings all 3 hr). A 2-1/2 in.
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- Layer-by-layer components with thicknesses
- Cross-section diagram
- Applicable code sections and test standard
- 6 related assemblies