Moist walls in the new building (base area) - exterior wall

Good evening! We moved into a newly built end-terrace house with our small child (1 1/2 years old) on June 28, 2017, and today we accidentally discovered these stains on the exterior wall (plinth area). Could this be moisture? And if so, should the builder look at it personally? Or should an expert in building inspections be called in right away? We always heat (underfloor heating) in the living room and also try to always remember to ventilate. It might also be worth mentioning that we had roller shutters installed afterwards in October 2017. Could it therefore also be due to water ingress? But then in the plinth area? We have also discovered some settlement cracks, which we were repeatedly told about. But here too, the cracks have a width of more than the limit value of 0.02 mm. I really hope that we get support/tips in this forum, because somehow our builder does not feel responsible... In addition, a door frame was incorrectly installed in the converted attic (we have already requested in writing for repair/replacement, but here too we receive no written feedback). Unfortunately, there are quite a few things that concern us, but the supposed moisture is now the icing on the cake :-( Best regards

Photos? Otherwise, you can only guess and not recommend anything.

I can show you cracks in every room. Several. On almost every wall.

Hello,
I have now uploaded the photos.

Thank you very much for the quick response.
I hope it can be clearly seen in the pictures.

These are our supposed settlement cracks. Would it be advisable to contact a building surveyor?

Thank you very much for the help!

Hello, in any case, an expert should be commissioned here. Remote diagnoses are a tricky matter but from the pictures, these are not normal settlement cracks and the moisture is certainly not due to ventilation or heating. Action should be taken here. Time and again, I experienced with my clients that too much time was waited. In any case, report the defect with a deadline and commission an expert/surveyor. The moisture issue does not have to be a big problem, but the cracks should definitely be examined closely. After 40 years of professional experience, I can only say: do not wait too long. Greetings from Bavaria

We also had moisture in one room. Serious: leakage! It can be fixed. We did not need an expert because the plumber reacted, looked at it, and fixed it. For us, it was the outdoor water tap.

We also have the cracks. The house will not collapse. But the site manager should also take a look here. For us, it is the partially missing mesh in the plaster, but also, as can be seen in your corner, normal. This is sealed with acrylic after one year. It is part of the painting work, which you have certainly done on site. You also probably have a Q2 plaster, which normally should be wallpapered. If you skip that, you have to live with some cracks. The wider ones should be examined.

First, you write a defect notice with a deadline. Templates are available on the internet. Send it by registered mail. Just Google it. Not a sloppy three-liner, but properly!

If there is no response after the deadline, you should hire a construction lawyer to take further steps.

You call in an expert if the builder refuses to acknowledge it as a construction defect. But be careful: not everything that looks like a defect is one.