Forgot the floor drain. What is the cost of subsequent installation?

Good day!

We built with a general contractor. We paid all invoices directly to the craftsmen. Now we have the following problem:

In our utility room, a floor drain was planned (marked in the building application and also listed in the construction service description). The house has been finished since June and this very drain was forgotten. After various phone calls and house inspections, the drain was already forgotten by the "structural builder" in the floor slab, etc. Our general contractor now wants to talk to him to "get to the bottom of it."
This means how much financial "compensation" he is willing to pay.

Based on past experiences, we have the premonition that they will try to fob us off with a few hundred euros (if at all).

Has anyone by chance had a similar experience or does anyone have an idea what a retroactive installation would cost? There are no pipes, the screed would have to be broken up, new tiles would have to be laid, etc.
How much money should one at least offer us? And if they offer too little, what is the best course of action?

Thank you in advance

I don't think anything can be done about it anymore. The effort would also be disproportionate. The utility room is probably fully usable?! In this respect, it will probably only come down to a few hundred (if anything), after all, you don't have a lower living value without this drain.

Why wasn't it realized before pouring the floor slab or at the latest when laying the drain pipes before the screed that the drain was missing?

I don't see the route to the lawyer, which surely some will recommend here. The reason is stated above.

The utility room is probably fully usable?!

No, with a burst hose on the washing machine or dishwasher, that makes the subtle difference between a small puddle and a major insurance claim. The culprit deserves to be hammered straight into the ground and the crater then professionally piped ;-) I don’t know any water in the world that would drain into compensation. Physics has no sense of humor.

I do not see the way to the lawyer, which certainly some will advise here.

The child has already fallen into the well here, but the following advice applies for future builders:
- Obtain legal advice before(!) signing.
- Consistently supervise the construction, as no one else will do it.
- Do not wait until acceptance, but promptly report defects (in writing).
- Insist on defect remediation.
- When accepting, absolutely(!) reserve rights regarding known defects.

No, with a burst hose in the washing machine or dishwasher, that makes the fine difference between a small puddle and a major insurance claim....

The fine difference between MUST and CAN. The drain in the floor may have its purpose, yet 99.9% of all households prove to you that it also works without it.

The broken washing machine is actually the most likely. However, nowadays all machines have at least one aquastop installed. If the hose breaks, the aquastop shuts off. Better is a full water protection, where even a leak in the machine stops the water supply. If your washing machine does not have full water protection, then that would be an argument and the cost of purchasing a good machine with full water protection a reasonable compensation.