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Work out concrete volume in m³ or yd³ plus how many bags you need for any slab, footing or column.
Estimate only. Always get 2–3 quotes from local trades before committing.
Volume = Length × Width × Depth × (1 + waste%)
Estimate the volume of concrete required for a rectangular pour and the number of bags. Add ~10% waste for spills, formwork bulge and uneven sub-base. Standard pre-mixed bags hold about 0.011 m³ per 25 kg bag (yields vary by mix).
Formula: Volume = Length × Width × Depth × (1 + waste%)
The pricing framework used by profitable contractors — from take-off to contingency — explained in plain language.
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