Concrete light shaft corner broken in shell construction - retention justified?

But if you are building without external construction supervision, my urgent advice would be to quickly hire external expertise now.

If I understand correctly, he already has an architectural firm that takes over the construction management for him, but not the commissioning of the individual trades. In this respect, that is his expert who is supposed to answer the question for his money whether the light well after the repair is equivalent to an undamaged light well.

As long as the component is not defective in function and even the appearance (strange discussion for a buried light well) is acceptable, there is no reason for any reservations here. This is shell construction and not goldsmithing.

As long as the component is not disturbed in its function and even the appearance (a weird discussion for a buried light shaft) fits, there is no reason for any withholding here. This is shell construction and not goldsmithing.

The light shaft is not buried at this point but later integrated into the terrace (surface flush with light shaft). If it were underground, it wouldn't be an issue at all and we wouldn't have seen it/we wouldn't care. Currently, there is a depression due to the broken-off corner and the grate does not sit properly at this spot because part of the supporting surface is also broken off. We will see how it looks after repair/what the site manager then says. The concern is only that we are told a lot and then no one shows up for repairs, hence the question of withholding until the repair is completed.

I see it this way: for a car with paint damage, even if it is repaired, I don’t pay the same price as for a car without paint damage. Different rules seem to apply in construction. We’ll wait and see how the repair succeeds and looks.

Thinking error:

All car manufacturers repaint vehicles before delivery – or do you think they throw away a 911 just because there is a scratch on the fender that was found internally?

You just don’t know.

So the comparison is flawed.

Otherwise: the craftsman must be given the opportunity to make corrections – that is legally his right. If the manufacturer has already devised a solution, I wouldn’t worry.

You will experience many other things before your house is finished – people work on this planet who are not free of mistakes, just as none of us here are...

The only concern is that we are being told a lot now and then no one shows up for the rework, hence the question of withholding payment until the repair is done.

The permitted withholding is double the cost of fixing the defects. Your site manager can give you an estimate for that. Otherwise, just make an estimate and have the shell builder explain why he thinks it will be cheaper.

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