Base plate with perimeter insulation underneath "soil" !!!URGENT!!! PICTURE

Hello,

I have a problem. We bought a house with a brick extension (strip foundation with a thin concrete layer of 10cm) that was torn down due to its construction and condition, and only the strip foundation (80cm deep) remained.
Now a larger extension is being built and the mason has extended the strip foundation. The new foundation is to be executed with 18cm and 2 layers of Q257 according to the structural engineer. Below that should be a perimeter insulation. Now I came to the construction site and found the following (see pictures).

Now, under the perimeter insulation there is normal "earth," topsoil that I removed from my gardening and the mason used it there. The perimeter insulation is also not laid fully flat as intended and is not straight. This cannot be right. Is it laid correctly? Concrete is supposed to come tomorrow. Are there regulations that say filling sand must be underneath? I also thought a foil is necessary. Please help me.

Further info:
A timber frame will be built on the foundation. No soil report available. Old strip foundations from the extension have been there for 30 years.

Would like to help you. Unfortunately, I have no experience with what you are building there. But that you put topsoil under a building, I have never heard of that and in my opinion, everything would have to be removed again.

Is that really the final state in the photos, just before concreting?

Why does the insulation not reach up to the formwork and why are there areas left out? And why do they form an apron to the existing structure, but not to the outside?... and the bottom strips, to my knowledge, are supposed to be laid exactly the other way around when using perimeter insulation... and above all not exactly in line, but actually always offset from each other. Otherwise, there is a risk that cracks will later form along the strips in the concrete.

The foil is there to prevent the concrete from losing water downwards. I don’t see that as too critical now with proper curing, but of course one wonders why they save on that – the 50€ should be affordable.

As for the "topsoil": The slab will later rest on the foundations. Provided you haven’t just dug up and thus loosened the soil between the foundations, this should not be a problem.

And the most important question, where is the steel ?

Are you building a garden shed ???? then that's enough!