Drainage in the basement - technically necessary or not?

The fact alone that the fill space is not filled with compactable material is already a defect?

That’s right, you ordered a service and should be able to expect it. As far as I know, in this case the defect must be reported to the contractor and the opportunity for rectification must be given.

At this point, I would seek a conversation with the construction company and get legal advice.

I informed the construction company of the defect with a deadline and a request for repair. The company responded that "they will only cover the excavation costs for the digging, but cannot understand why a drainage system, which is not approved but still works, should be removed. They will not share in the further costs (soil disposal, new fill sand, etc.)"!

The good thing is that an independent expert also identified and documented the defect. I presented the expert report along with the defect to the company, but they insist on the statement written above. The construction manager and basement contractor work together on many construction sites and both argue this way.

The construction manager stated that it is not proportionate to remove this good drainage system now.

To be honest, I don’t know what else to say when even expert reports are talked away? Is the unpleasant step to a lawyer the last option?

How are you building? Turnkey with a general contractor who also does the basement and earthworks, or with individual contracts or assigning the basement + earthworks yourself? With turnkey, you have relatively few options during the construction phase, since the complete service is only to be provided at handover. Withholdings due to defects are accordingly difficult. You can only document the defects, point them out again, and refuse to accept the defective parts at handover or have them noted as defective in the acceptance protocol. If you have assigned the relevant work yourself, it is easier for you, since the service must already be provided without defects now. Then go to a lawyer and clarify how you can withhold money legally.

Hi

How are you building? Turnkey with a general contractor who also does the basement and earthworks, or with individual contracts or awarding the basement and earthworks yourself?
With turnkey you have relatively few options during the construction phase, as the complete service is only to be provided at handover. It is also difficult to withhold payment due to defects. You can only document the defects, point them out again, and at handover refuse to accept the defective parts or have them recorded as defective in the acceptance protocol.
If you have awarded the respective work yourself, it is easier for you, as the service must already be provided defect-free now. Then go to a lawyer and clarify how you can legally withhold money.

Hi we worked with individual contracts! Then I will probably contact my lawyer! Thanks ☺️

You insisted on a drainage system that is not necessary, and the contractor thinks: what nonsense - well, I'll just throw in a pipe, then he'll be satisfied. You could also just leave the pipe there (it doesn't bother anyone) and not pay for the drainage. Wouldn't that be an option?