Concrete Foundation - Earthwork takeoff

[martin888888]

We have a 3 story building with a partial concrete footing and partial slab on grab. Is there normally a rock section underneath this slab and footing. Trying to do an earthwork takeoff for the excavation

 

[DirtPusher]

I would check the specs and/or details.
Differing site conditions may require different
support/drainage courses under slabs/footings.
If you have access to the geotechnical report,
check for recommendations there also.

 

[Dozerman56]

Normally there's a capillary barrier of clean stone under a slab on grade, check your structural and architectural drawings. I'd be surprised if there's supposed to be anything under the footings unles you get into an unsuitable soil condition, but again check your structural details and notes.