Foundation cushioning Town & Country house construction service description

Huh? Almost all companies I spoke to define the soil survey as a construction-side service.

How much excavation you will have is only told to you by your soil survey... the plot can be whatever it wants and also the correct height above street level... if the soil cannot be compacted or you have problems with groundwater...

We had to pour 2.5m deep concrete foundations under the load-bearing walls (also load-bearing interior wall) = 50m³ excavation and 50m³ concrete. Then almost 100m³ of gravel, because the plot was below street level, luckily we knew that beforehand. The gravel bed must also protrude, it will be significantly larger than your slab. Oh, and the slab according to structural engineering is also thicker, higher-grade reinforcing steel, etc.

Those 45cm including is a joke, the additional foundation cost 25,000 EUR...

That’s a lottery. A coworker had peat = pile foundation. 40,000 EUR extra, though in 2017. Today definitely 50,000 upward.

The construction report provides guidance but no 100% cost certainty. Unless you check the soil conditions at many points. It is quite possible that the soil report says something different than the earthworks contractor who then did the digging.