Error in house construction - How did you deal with it?

Would have fixed the error myself. The team has a right to a remedy. From what is heard, it makes it worse.

There are errors that are unacceptable and errors that are simply annoying. You have to weigh it up. Expert, possibly lawyer. You have to invest time and money with an uncertain outcome.

Some errors are cheaper and quicker to fix yourself.

A car is industrial production. If a feature is missing, you get a credit note. If you have a lemon, it is your time and money to take it to the workshop. Not all repairs are covered either. This happens despite standard procedures, despite the assembly line, despite quality control.

We did not build, but renovated, and gradually the shoddy work or simply mistakes that sometimes happen became apparent.

1. The drywall installers did not seal the insulation tightly enough to the roof in one spot, and at Christmas condensation water dripped from the ceiling. It still hasn’t been fixed because we had to wait for suitable weather to open it up. At least the boss has been quite cooperative so far and promised to have the mistake corrected.
2. The electricians mislabeled and wired quite a few things incorrectly. Someone is finally coming tomorrow to check and correct it – among other things, the two electric stoves were labeled exactly backwards, which we luckily noticed BEFORE the work on the stoves, also several lamps were wired incorrectly where we have multiple in one room, etc. Here too, the boss has been cooperative and understanding so far.
3. Currently we are having issues with the plumbing company. They installed our shower back then and drilled into the tiles, causing a hairline crack that initially no one noticed (in the corner). The crack likely gradually enlarged due to the movement of the sliding doors, and because of the use of non-self-sealing anchors, no one knows how long (the bathroom is 1.5 years old) water was leaking behind the wall until it appeared in the ground floor three weeks ago. Result: a €120 invoice from the tiler who had to redo and seal the water-damaged drywall behind the tile and replace the tile, and we expect about €200 in installer hours. Who will cover the whole thing still needs to be clarified. The company was otherwise always correct and diligent and we hope they recognize and take responsibility for the mistake. We will close the hole in the ceiling ourselves once everything is perfectly dried.
All in all, we can now say that the tiler has been the only craftsman who made no mistakes so far – out of a total of 5 companies. Overall, we had real mistakes with 3 specialist companies. We had no shoddy work with the roofers either, but they only installed 2 roof windows – however, with external blinds, which we had not ordered at all. The agreement there was that we pay for the blinds but not for the roofer’s hours. Fortunately, we had done the rest ourselves anyway.

We didn't build, but renovated, and gradually the botched work or simply mistakes that sometimes happen became apparent.

1. The drywall installers didn't seal the insulation tightly enough to the roof in one spot, and at Christmas, condensation dripped from the ceiling. It still hasn't been fixed because we had to wait for the right weather to open it up. At least the boss has been quite cooperative so far and promised to have the error fixed.
2. The electricians mislabeled and wired quite a few things incorrectly. Finally, someone is coming tomorrow to check and correct - among other things, the two electric stoves were labeled exactly backwards, which luckily we noticed BEFORE the work on the stoves, also a few lamps were wired incorrectly, where we have several in one room, etc. Here too, the boss has been cooperative and understanding so far.
3. Currently, we are having fun with the plumbing company. They installed our shower back then and drilled into the tiles, causing a hairline crack that no one initially noticed (in the corner). The sliding door movement presumably caused it to gradually enlarge, and because non-self-sealing anchors were used, water ran behind the wall who knows how long (the bathroom is 1.5 years old) until it came out on the ground floor about 3 weeks ago. Result: a €120 invoice from the tiler who had to redo and seal the water-damaged drywall behind the tile and replace the tile, and we expect about €200 in labor hours. Who will cover all this still needs to be clarified. The company was otherwise always proper and earnest, and we hope they acknowledge and take responsibility for the error. We'll patch the hole in the ceiling ourselves once everything is perfectly dry.

In summary, we can now say that so far the tiler has been the only craftsman who made no mistakes—out of a total of 5 companies. We had real mistakes with 3 specialist companies. We also had no botched work with the roofers, but they only installed 2 roof windows—however, with external blinds that we hadn't ordered at all. The agreement was that we would pay for the blinds but not for the roofer's hours. Fortunately, we did the rest ourselves anyway.

Regarding 1. He is currently not answering the phone.

Regarding 2.: The electrician was here, fixed the errors, and relabeled everything for us. This is now completed and covered under warranty.

Regarding 3. The plumbing company refuses to pay the tiler's invoice. They say they did everything as usual. After some back and forth, we are at least not being charged for the labor hours, but they still don't want to cover the tiling issue. The foreman even cheekily suggested that we simply report the damage to our insurance. And the workers no longer want to come to us; we had actually commissioned them to replace a radiator; after this issue, however, we no longer want to see the company. We have now ended the cooperation. Three weeks without a shower, a hole and slight mold in the ceiling, dirt, noise, 4 appointments with craftsmen, €120 (plus what closing up the ceiling will cost us) — that's what we're left with.

And for things like this, you hire local specialist companies.