Damages caused by screed work. Who is liable? How to proceed?

Hello dear forum users,

we are building a house with an architect. Recently, screeding work was carried out at our place. During this, the shell construction, which was supposed to remain visible, was heavily soiled and damaged in several places.

In my opinion, this constitutes a defect because the other trade was not sufficiently protected. However, I wonder how I should proceed to achieve defect remediation.

The screeding company does not want to take any action because, in their opinion, it is "shell construction" and nothing could have been done about it. According to the opinion of other companies that were present, what they did was a big mess. From their reports, I have learned that normally it goes differently. In particular, the hoses are secured with straps to control vibrations/shocks and thus minimize the likelihood of such damage. However, I could not find any DIN standard that would require this.

Is it possible to hold the architect somehow liable, since ultimately a defect-free object will not be handed over? He also did not supervise how the work was carried out. He is completely abandoning us on this matter as well. Does he have no obligations? ([wurde für alle Leistungsphasen beauftragt])

I would be very grateful for any tips.

I can hardly imagine a visible raw construction wall, but if that is the plan, A. has to deliver it that way. His problem. You are his client, he deals with the craftsmen, he receives their invoices, he approves them. Or insists on corrections.

Photos? Is a shell wall not plastered...?

Did the screed company know through the site manager that it was exposed masonry?
Which can be proven by the item in the tender or later in the order regarding the masking of the walls.

If nothing exists, the screed company can possibly prove that masking was not part of the contract.

What the craftsmen say about a shell construction, .... sorry, at most it’s about broom clean.

Apart from whether airtightness is given at all without plaster on masonry
and whether this is also provided for as such in the thermal insulation certificate.

Pictures?

Defect?

Your architect is funny. It is his job to hand over your house free of defects.

By the way, a DIN is not a regulation but a recommendation. So you don't need to come with such things at all.