How it is calculated
These are outside sizes. A blinding layer, a wider footing, and extra for soil that caves in are not included.
V = (L×W − (L − 2t)×(W − 2t)) × depth
Where the numbers come from
- Outside length — unit in the field: m
- Outside width — unit in the field: m
- Strip thickness — unit in the field: m
- Depth — unit in the field: m
Example
An outline of 10×8 m, a strip of 0,4 m, and a depth of 1 m give 13,76 m³.
Questions
The strip is not closed?
Then multiply the length of the axis by the width and the depth yourself. This form is a closed rectangle.
Is the thickness the trench width?
Yes, the horizontal thickness of the strip wall.
Rebar?
A separate calculator finds its mass.