ᐅ Stainless Steel Foundation Earth Electrode V4A – What Are the Requirements?

Hello fellow home builders,

I have the following question: At the final stage of the planning phase, the construction company is offering me a "foundation earthing made of V4A stainless steel instead of the standard."

My question is: Can they charge an extra fee for this?
Isn't the above-mentioned quality grade now mandatory in construction (DIN 18014)?

In the building specifications, it states:
"A foundation earthing made of galvanized strip steel according to VDE regulations will be installed in the foundation slab. For the initial calculation, we assume a soil stiffness modulus of >= 15 MN/m2, a maximum topsoil thickness of 20 cm (8 inches), and a frost protection depth of 80 cm (31 inches)."
Background: We already ordered the waterproofing system known as the "black tank" during the offer phase, which is also being used for the build (DIN 18533 W2.1-E).

Thank you very much and best regards from Stuttgart.

The foundation earth conductor is embedded in the concrete on the steel reinforcement of the slab; using galvanized steel there is perfectly fine.
This is not possible with a white or black tank. In that case, the grounding must be installed around the house in the soil. Therefore, V4A stainless steel is required. This is called ring grounding.