Provision interest and deadlines of the house building company in the work contract

Because the house will only be erected in the last week of September and the interior work will still be done by Streif Haus. I do not expect a handover before December...

The period is not yet. According to the contract data you provided, it is realistically possible that moving in will not occur before October. You must then check your contract for any further delays to see what has been agreed upon regarding deadline extensions. But in no case will there be any interest refunds or similar for the period 06-09/2023.

Why then are construction phases and deadlines agreed upon in the contract for work?

Yes, I know you don't want to hear that now, but no general contractor in the world will pay you provisioning interest. With the reminder, you wouldn't even have drawn a faint smile from the general contractor. What exactly does the contract state regarding when and how much you will receive? If nothing is explicitly stated there, then all you can have are valerian and kind words.

Are there any tips from the community on this? Thanks in advance!

Yes! Forget it..... :)

GD (Words Words Words)

The reality is that we have been given our installation date at the end of September. This means for us that as of 01.06., the twelve-month, interest-free disbursement period at the bank has expired and we recently had to pay interest of 1,100 euros for the first time (the large chunk for the actual house is still with the bank).

So you already took out the loan more than half a year before your conditions were met. That makes the disbursement interest mainly your fault. That would not matter anyway, because disbursement interest is your matter; you could also have chosen 18 months. Is a concrete completion date specified in the construction contract or are the indicated times (x months for y) binding? If not, you will not get anything at all. If yes, you can discuss a penalty for delay in the end.

I find it rather unusual that there are several deadlines in the contract and also wonder how exactly they are formulated. Otherwise, I know it more like having some kind of (often generous for the manufacturer) deadline for completion/delivery. With us, it's like this (not Streif Haus) and then also there are apparently about 20 exceptions when they might still be allowed to exceed it. (Our developer, for example, had even added two additional sentences for "pandemic due to a pathogen according to IFSG," just in case)

I don't think you can claim anything if any intermediate milestones are not met; that is probably only possible once the actual completion date is missed. And I doubt that would already be the case 3 months after the building permit.

And currently, no interim deadlines have been missed yet according to the data that TE has provided us.