Concrete guide
Concrete footing guide
Strip footings use the same volume logic as slabs, but the run length is often the critical measurement. Break long runs into sections if the depth changes.
Length
Measure the full footing run along the trench centerline or outer edge, depending on how the formwork is set out.
Width
Use the actual footing width, not the wall width. The footing is often wider than the wall it supports.
Depth
Depth is the vertical concrete thickness below grade or to the top of the footing if you are checking formwork volume.
Example
Footing example
A 20 m footing, 0.6 m wide and 0.3 m deep, uses 3.6 m3 of concrete before waste.
With 5 percent waste, the adjusted order volume is 3.78 m3.