20cm ceilings, 7cm ventilation ducts - Can this work?

Hello everyone,

perhaps the topic has already been discussed. According to my current knowledge, the weakening is too great. But our structural engineer thinks it is negligible. Attached is a plan excerpt.

Maybe there are already experiences on this topic here.

Best regards and thanks in advance.

AvH

According to my current knowledge, the attenuation is too high.

Where does your knowledge come from? Are you a trained structural engineer or an internet crystal ball reader?

But our structural engineer says it would be negligible.

If the professional says "yes" but you know better, what do you expect from laypeople here?

The usual size here for the GUs is 22, my structural engineer wanted 24. Whether 20 is sufficient should be determined by the structural engineer..

I would recommend removing the personal data from the plans.

Are the 7 cm even deducted from the 20 cm? Or are they part of the structure and the load-bearing structure is not compromised at all?

Best regards

Thank you very much for the RM. The allowed total height above BZH is fully utilized. Accordingly, thicker ceilings will be difficult. I can hardly imagine 20cm either. Also in terms of the upper reinforcement layer and concrete cover. I will press the point again... otherwise it will have to go into the screed. But even there, with a total build-up of 15cm, there is hardly any space... Regards

Attached is a plan excerpt.

Has your project shrunk? – I remembered it being bigger.