Usually measured in m3, ProCalc uses m2 of any site cut exceeding 300mm (or site scrape). We’ve done this for ease of use.
You do not have to allow for edge trenches for example or a standard waffle slab.
Instead it’s for a site cut into a sloping block or basement excavations (if you select that project type).
Please note: If the spoil is used as fill on site, halve the m2 area you apply.
Extensive site fill brought to site – exceeding 300mm depth – can be estimated by allocating half of the m2 area to be filled (over 300mm deep).