Foundation cushioning Town & Country house construction service description

Hello,

Earthworks
"The topsoil will be removed up to a thickness of 30 cm. The excavated soil will remain on the property. The height deficit will be replaced with frost-resistant material of the foundation cushion. According to geotechnical requirements, the foundation cushion will be increased up to 45 cm. A PE foil will be applied as a separating layer on the frost-resistant material."

Question:
Which material is Town & Country contractually obligated to use for the foundation cushion? Is RCL1 compliant with the contract, or can I insist on gravel or frost protection material?

Earthworks
"The topsoil will be removed up to a thickness of 30 cm. The excavated soil will remain on the property. The void will be replaced with frost-resistant material for the foundation cushion. If required by geotechnical necessity, the foundation cushion will be increased up to 45 cm. A PE foil will be applied as a separating layer on top of the frost-resistant material."

Question:
What material is Town & Country contractually required to use for the foundation cushion?
Is RCL1 contractually compliant or can I insist on gravel or frost protection material?

We do not know your contract, but presumably RCL1 will have to be accepted if no other factors (load-bearing capacity, hydrological conditions, etc.) speak against it. So why should you be able to insist on something else? Moreover, frost protection has nothing to do with RCL1 or gravel. It can theoretically be done with both and is hopefully included in the construction service description.

You should rather be aware that more soil excavation and possibly removal will be necessary at Town & Country than is included in the construction service description.
The list of items designated as "by the builder" may be longer than with some other general contractors.

Warning: As always, this is a layperson's opinion. For similar topics related to Town & Country, feel free to use the search function.

What material is Town & Country contractually required to use for the foundation cushion?

Frost-resistant and structurally sufficiently load-bearing.

Rather, you should be aware that with Town & Country more soil excavation and possibly removal will be necessary than is included in the construction service description.
The list of items designated as "provided by the builder" might possibly be longer than with some other general contractors.

The 30 cm are only sufficient if the plot is well leveled and the soil underneath is good. Removal is not included at all; as long as you build without a basement, I would always consider saving it and spreading the excavation on the plot. There really isn't that much excavation.
The list of builder-provided services is somewhat longer corresponding to the price level but, to my recollection, still acceptable.

How much excavation you will have can only be told by your soil survey... the plot can be whatever it wants and also at 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 (including load-bearing interior walls) = 50m³ excavation and 50m³ concrete.
Then almost 100m³ of gravel, because the plot lay below street level, luckily we knew that beforehand. The gravel cushion also has to extend beyond, it will be significantly larger than your foundation slab.
Oh, and the foundation slab is also thicker according to structural engineering, with higher quality reinforcement steel, etc.

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

That’s a wildcard. A colleague had peat = pile foundation. 40,000 EUR surcharge, but that was in 2017. Today certainly 50,000 upwards.

The list of things designated as "bauseits" might possibly be longer than with some other general contractors.

The problem is that much is not labeled as 'bauseits.' It simply is not mentioned. The construction specification does not state what concerns your property, but only the house.

With us, the basement builder (commissioned by the general contractor) emphasizes that he absolutely must adhere to the soil report. And who commissioned the soil report? Surprise - the basement builder! That means everything is written in a way that allows the basement builder to save on materials and costs, while the client pays more for earthworks and special backfilling, etc. (because the earthworks are usually designated as "by the builder" by the general contractor). It is becoming increasingly difficult for me to believe in the independence of various "experts"...