Calculation of volume of topsoil and filling sand for a sand slab

Hello!

We are having a dispute with a company that installed the sand base.
It was about a work area of 14 x 15.5 m (217 sqm).
The installed sand base had an average thickness of about 30-35 cm, and the same thickness of topsoil was removed.

The question now is,
- how much topsoil must be transported away
- how much fill sand must be brought in and installed?
- what volume changes must be expected for topsoil and fill sand?

Thank you in advance for any suggestions.

Regards

Stefan

PS: Hope this belongs here

How is the dispute? It depends on how the billing is done and what is stated in the offer/[LV]. It can be based on m², m³, or tonnage... Topsoil is often billed by m², disposal by t, and the subgrade by m² or m³.

Billing was still done per qm for the removal of the topsoil and per cbm for the installation of the fill sand and the transport of the topsoil.

From the contractor's side, contradictory values have been presented from my point of view.

Actually not.
Topsoil area: 217 sqm
How much he has to push away he will only know once it is gone.
Installation then depends on how much he has pushed away, at 35 cm it is 76 cbm.
The removal of the topsoil could be debated. It is usually weighed, but th. should not cost anything anyway, as it is resold and not deposited.

Yes, but it must be said that he said the first time that he had installed 250 cbm of fill sand and removed 140 cbm of topsoil. I doubted the figures, whereupon he corrected them to 210 cbm of fill sand and 120 cbm of topsoil. It must be said that the contractor had the order to remove a maximum of half.

Solid mother soil loosened up, you may add another 1/3 to the volume. But there should be coverings for weighing. Were the 14x15m the work area or the dimensions of the foundation?