The ratio of cement to river sand and stone determines the strength of the concrete. Here is a cheat sheet to ensure that you have the right strength of concrete for the job.
Your tools:
• Bucket / Tin
• Spade
• Wheelbarrow
Large batches
Low-strength concrete suitable for house foundations.
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To make 1 cubic metre of concrete, you will need: 5 ½ bags cement + 0.75 cubic metres sand + 0.75 cubic metres stone.
Medium-strength concrete suitable for domestic floors, footpaths and driveways.
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To make 1 cubic metre of concrete, you will need: 7 bags cement + 0.70 cubic metres sand + 0.70 cubic metres stone.
High-strength concrete suitable for precast concrete, heavy-duty floors.
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To make 1 cubic metre of concrete, you will need: 10 bags cement + 0.65 cubic metres sand + 0.65 cubic metres stone.
Small batches
Use containers such as buckets, drums or tins. Use the same size container for measuring all the materials in a batch.
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