Measures · Predalles slab
Predalles slab pre-sizing FREE
Work out the thickness of a Predalles (precast panel) slab from its span. Below the result you find the formula and the standard.
Indicative pre-sizing. It does not replace a structural calculation signed by a licensed engineer. For seismic zones with agS (design ground acceleration) > 0.15g, long spans or use classes III/IV → talk to a structural engineer.
Pick a calculation from the list to start.
Formula, example and standard
H ≈ L/25 (typical minimum 20 cm)
Example with the starting values (Span L: 5 m): Total thickness H ≈ 20 cm. Precast base panel: 4-6 cm · always check the manufacturer's data sheet.
- Predalles = precast RC panel + lattice girders + cast-in-place topping.
- Typical thickness 20-30 cm for residential, up to 40 cm for long spans.
- Always check the data sheet of the specific manufacturer.
Source: NTC 2018 §4.1.10 · manufacturer data sheets · studiopetrillo.com
Indicative pre-sizing: it does not replace a calculation signed by a licensed engineer.
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