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Concrete & structure

Concrete Slab Calculator

Concrete for a floor slab or raft, including the waste allowance and the mix that fills it.

A domestic ground slab is usually 100–150 mm; a suspended slab is thicker.

The nominal mix. C25 is the usual choice for suspended slabs and columns.

%

Spillage, over-excavation and what stays in the mixer. 5% is normal for a ready-mix pour.

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