Correct formulation for a waterproof basement

My house builder offers a basement sealed according to DIN 18195-4 according to the construction and performance description. Our consultant always refers to "WU-Keller" in our preliminary designs. He briefly explained to me in a quick meeting that the walls are cast on site and something from the base slab protrudes into the walls from below so that the path for water is as long as possible. The weak point is the connection between the base slab and walls. In addition, something is glued to the outside of the walls.

As you can read, I have no idea about the execution, but what kind of basement should I put down in writing now?

White tank according to DIN 1045 + external wall waterproofing with bitumen membrane according to DIN 18195-6? And internal waterproofing of the base slab with bitumen membrane with aluminum insert?

I somehow put together these formulations, but what is the correct term? The basement should be "simply" waterproof...

Regards Aloa

What kind of burden case do you have?

I have no idea. The new development area will be developed by next summer and so far there haven't even been any notary appointments. My turnkey provider is making a cost estimate for me at my request. I want a waterproof basement to be taken into account and to have this included in the correspondence from the very beginning. I just don't know how...

You should first wait for the load case - otherwise, they are totally unlaid eggs. A real "white tank" costs a significant extra charge - and it’s not done with WU concrete and joint sheets alone (this is a normal reinforced concrete basement, which is also made with WU concrete).

Bitumen mats don’t go on the outside either, and according to some expert opinions, you don’t have to put them on the inside either (we installed them anyway - but nothing aluminum-coated (why should we?)).

I would like a white tank to be considered as the worst case in the cost estimate. Is the term white tank alone sufficient here without specifying standards and additional sealing measures?

Probably not, if he has already explained it to you like that.

Apparently, extremely many companies have a hard time with something like that – I just read up on it, but according to a green forum, there are always defects (as long as you don't build with them :D).

You just have to google the standard you mentioned, then you'll immediately know that it's not a white tank, but a normal concrete cellar.