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Concreting · Free Calculator

Rebar Spacing Calculator

Calculate rebar spacing, quantity, and weight for concrete slabs and footings. Based on Australian Standard AS 3600 requirements.

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metres
metres
mm
Results

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Pro Tips
  • Standard residential slab reo: N12 @ 200mm centres both ways
  • Minimum cover: 40mm for slabs on ground (AS 3600)
  • Lapping length for N12: minimum 500mm overlap
  • Chairs/bar supports every 1m to maintain correct cover
  • Order 5-10% extra for laps, wastage, and cutting

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— Jarrod A., Founder & QBCC-Licensed Concreter

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