Construction company insolvent, how to proceed further?

Of course, who else. It is not about the insolvency but about the concerns arising from the construction contract/construction project.

However, against the background of insolvency law (or from the perspective of subordinated creditors, rather insolvency injustice) – simple mathematics: if a factor is close to zero, the result is also close to zero. From a construction contract law perspective, the client (owner) may at most be right, but a factor of zero point something helps him little. His enforcement costs are nevertheless based on the full value in dispute without a depreciation factor. Even for the assessment of procedural economy, the longer lever lies with the expert in insolvency law.

Please do not speculate or guess here.
The insolvency administrator will also oppose the OP with a specialist lawyer for construction law.

I do not share this speculation/guess at all: the insolvency administrator will regularly represent himself, and this will not be interpreted as negligent endangerment of the assets he represents. If he loses spectacularly – so what, then he simply has even less to distribute – it will not harm his fee.

We are unsure whether we should take legal advice for a mid four-figure amount (our retention of defects including 2x pressure surcharge), because lawyers do not work for free either.

My fee-free opinion – not legal advice – is: 1. all lawyers (and without them you are lost) do not work for free there, but the construction lawyer is more likely to be unsuccessful than the insolvency lawyer; 2. forget about a “pressure surcharge” against an insolvency debtor. Incidentally: apart from your value in dispute and thus the lawyer’s fees, the pressure surcharge does not (any longer) increase anything.

I have read on the Internet that all claims that were valid before the actual insolvency are set-offtable within the framework of insolvency, so the set-off prohibition in paragraph 95 InsO paragraph 1 sentence 3 is not supposed to apply.

If the Internet says so, then of course I am powerless ;-)
Theoretically, it makes a difference whether claims already arose before insolvency. In practice, however, as a subordinated creditor in insolvency you can mostly “write off” what you theoretically would have been entitled to receive. By the way, what you call “actual insolvency” (i.e., probably the phase of permanent insolvency administration) only means that insolvency has been determined as definitely having occurred; it may actually have existed earlier. Investigations often last for years as to whether the filing was delayed (and these investigations often end unsatisfactorily from the perspective of truth-finding). Insolvency law can only be grateful to laypeople for the hope of understanding more of life’s other matters.

Theoretically, it makes a difference whether claims arose before the insolvency. In practice, however, as a subordinated creditor in insolvency, one can mostly "write off" what one theoretically would have been entitled to receive. By the way, what you call the "actual insolvency" (probably the phase of permanent insolvency administration) only means that the insolvency has been officially established as secured; it may actually have existed already before. Not infrequently, this is followed by several years of investigations into whether the filing was delayed (and these investigations often end unsatisfactorily from the perspective of finding the truth). Insolvency law can only make laypeople hopeful of understanding more about the other things in life.

Ok, that means, according to your statements, the odds are generally bad as an insolvency creditor. That means, if one has a defect retention of about €3,000 without a pressure surcharge, it is hardly worth taking the risk of arguing with the insolvency administrator, since one would still have to bear attorney fees as well as possibly court costs.

Ok, so according to your explanations, the cards are generally stacked against insolvency creditors.

I explicitly spoke of subordinated creditors, and this category includes builders and homebuyers. Insolvency law theoretically requires the filing of a suspicion of insolvency based solely on criteria that can also be temporarily met. In the vast majority of cases, however, the legal presumption of insolvency remains permanently accompanied by an actual insolvency, and the company moves from the palliative care ward to the hospice. Then the tax office and health insurance funds become the largest mandated heirs, and only the leftovers from the feast end up at the children's table. You can still rattle your saber a bit against your feeling of powerlessness, but it will trigger as many NATO missions as a bicycle theft in Münster. Lighting a candle is the most a Protestant can still do. Mumble to yourself that you have been wronged, if that helps you. Straighten your crown, life goes on! (it has to...) We currently have three Traumhaus-Hildmann threads here, where in my assessment things will continue after the turbulence, but the typical insolvency case is actually what used to be called bankruptcy.

So, if you have a defect retention of about €3000 without a pressure surcharge, it is hardly worth taking the risk of arguing with the insolvency administrator, since you still have legal costs and possibly court costs to bear.

According to my aforementioned image, after saber-rattling, you might end up with only the hilt left, and a broken blade. ... he only finds the head and the noose on the back part of the wagon ;-)

However, against the background of insolvency law (or better said from the perspective of subordinated creditors insolvency injustice) - simple mathematics: if a factor is close to zero, the result is also close to zero. From the perspective of construction contract law, the client may be maximally right, but a factor of zero point something helps him little. His enforcement costs are nevertheless measured against the full value in dispute without a depreciation factor. Even just for assessing procedural economy, the longer lever lies with the insolvency law expert.

That is completely correct. If I understood the OP correctly, in his case, as in mine, it is about whether he still has to make outstanding payments to the insolvency administrator/construction company or how and by whom his defects will be rectified or what will happen to his warranty in the future. Usually also, when and whether he should or must return his completion bond.
That means he has no claim against the insolvency administrator from the insolvency estate but is still sitting on perks that the insolvency administrator will soon reclaim.
All comments here are absolutely correct; I would not recommend anyone to take up the fight without insolvency law advice and legal expenses insurance.

The practice looks as follows here. After a legally secured takeover of the insolvency administration, the insolvency administrator will first push for payment of the outstanding balances from the contractual partner (here the client) or the return of the completion bond.
If this does not happen because there are still defects open or contractually assured services have not been fulfilled (here blower door test), a payment lawsuit comes very quickly.

I do not share this speculation/assumption in the least: the insolvency administrator will regularly represent himself, and this will not be interpreted as negligent endangerment of the assets he represents. If he loses with drums and trumpets – so what, then he simply has less left to distribute – that will not harm his fee.

That is speculation again; if it comes to a court payment lawsuit, this will be conducted exclusively by a commissioned lawyer, since the insolvency administrator is not entitled to file a lawsuit in court himself – even if he happens to have the professional competence. But this leads too far here and is irrelevant.

The OP basically has only 2 options:
- To settle all outstanding claims, return the completion bond, and carry out the defect rectification at his own expense
or
- To cease payments, document the defects, and under no circumstances fix them himself, get a lawyer, and enter into a legal dispute.

In my case, I chose the second option; in the end, a judicial settlement was reached. After accounting for the lawyer's fees (in a settlement, the plaintiff/defendant bears their own attorney fees), I was partially able to cover the costs of defect rectification – but no more than that.
From this experience, I would not pursue this way again today. If the sum of the defects/outstanding services is still in the four-digit range, I would swallow the bitter pill. A legal dispute takes years, costs endless nerves, and a lot of lifetime.

As a result of this multi-year legal case, I took out a client legal expenses insurance for my next construction project, which also covers new builds. I can only recommend it, though it only helps to a limited extent.

It should be clear to everyone that my experiences do not constitute legal advice. I can only report what I have experienced myself and hope that this helps the OP or other interested readers to make their own decisions.

The OP basically has only 2 options: - Settle all outstanding claims, return the completion bond, and carry out the defect repairs at their own expense or - Make no further payments, document the defects and under no circumstances remedy them themselves, hire a lawyer, and enter into a legal dispute. In my case, I chose the second option, and in the end, a court settlement was reached. After accounting for the attorney's fees (in a settlement, the plaintiff/defendant bears their own legal costs), I was partially able to cover the costs for defect repair – but not more. From this experience, I would not pursue this path today. If the sum of defects/outstanding services is still in the four-figure range, I would bite the bullet. A legal dispute takes years, costs an enormous amount of nerves, and much lifetime. As a result of this multi-year legal case, I took out builders’ legal protection insurance for my next construction project, which also covers new builds. I can only recommend it, but it only helps to a limited extent.

Thank you for the report of experience; it is very valuable for me. We have already objected to the request to pay the remaining amount due to outstanding defects; the provisional insolvency administrator only responded that he is not responsible for defect remediation. Nothing more. That means, as soon as the actual insolvency proceedings are opened, we will probably receive a letter with a payment lawsuit. We also took out builders’ legal protection insurance before the construction, and well, unfortunately, I just discovered that the legal area "insolvency" is excluded there :-(.

We also took out builder's legal protection before construction started, and well, unfortunately I just discovered that the legal area "insolvency" is excluded there :-(.

That's really bad, which insurance is that? With ÖRAG this is not excluded.