Sqratch Tools / Structural & Shell / Concrete Slab & Footing Calculator
Concrete Slab & Footing Calculator
Enter your slab dimensions to accurately estimate the volume of concrete required. The calculator instantly breaks down the total into standard pre-mix bags so you know exactly what to order, saving you time and material waste.
Basis & Assumptions
- Volume = Length × Width × Depth × (1 + Wastage%).
- Standard nominal yields: 1 × 40kg bag ≈ 0.018m³; 1 × 80lb bag ≈ 0.6ft³ (0.017m³).
- Actual bag yields vary slightly by manufacturer, mix design, and water ratio — use as an estimate.
For quick design checks and study — not a substitute for your local Development Control Regulations, NBC provisions, or a licensed professional's judgement. Always verify against the bye-laws that apply to your site.
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