RC Slab Thickness (Span-Depth Ratio)
PROEstimate minimum reinforced concrete slab thickness from span-to-depth ratio rules in AS 3600 or ACI 318.
BEng Mechanical Engineering (Hons), CMIOSH, LEEA Member
Mechanical engineer and certified lifting equipment examiner with 18 years in heavy industry, structural steelwork, and crane operations across construction and resources sectors.
1 April 2025
Professional verification required
These calculations are provided for estimation and educational purposes only. Results must be verified by a suitably qualified and licensed engineer before use in any design, specification, or construction context. Numly accepts no liability for decisions made on the basis of these results.
Minimum thickness from Table 2.4 (span/depth ratios) or deflection calculation. Seismic ductility class determines bar requirements.
Standards New Zealand
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