Attic expansion - is knee wall/short wall interior insulation sensible/necessary?

Hello,
we are currently in the process of converting our roof. On two levels (attic + loft), 160 sqm of living space is being created.

In the area of the first level, we have a 40cm high concrete knee wall on which a 60cm high glued laminated timber beam was placed to raise the roof.

Current structure of the concrete knee wall:


The area outside of the placed purlin will then be adjusted to the level of the remaining exterior facade during exterior plastering work using insulation.
Regarding the rest of the masonry:
The house was built in 1986. It was constructed from 36.5cm Poroton bricks + 2cm lightweight plaster. Initially, no facade insulation will be applied! In other words, the knee wall will have to remain as it is from the outside.

Is the structure of the knee wall "insulation" (pre-built Poroton + Heraklith + lightweight plaster) from back then sufficient in relation to the rest of the masonry (36.5 + 2), or is it recommended to additionally insulate from the inside? My main concern is that the dew point does not shift and that later moisture/mold does not accumulate on the inside of the concrete...
If additional insulation from the inside, how and with what?

Perhaps also interesting:
The new roof has 20cm insulation between the rafters + 10cm wood fiberboard on the rafters.
A floor heating system will be installed in the entire lower area of the apartment.

Thanks in advance for the tips!
Regards

Hmm over 480 views and no one dares?

That might be related to the fact that this is a question that can only be answered after a thorough recording of the current situation followed by an analysis shaped by expertise. Go to a structural engineer or something and ask them to handle it. That is money well spent.

Best regards

K1300S

You said it nicely, I just wonder what use a structural engineer is to me here?

Hello,

...
I just wonder what use a structural engineer is to me here?

I hope this question is not meant seriously now?

You want to add a floor to an existing building from 1986, for which a structural analysis was created based on the actual use. Now you are changing the envelope, adding several square meters that will be used constantly. Don’t you also think a structural engineer should recalculate whether the existing building is adequately secured for the upcoming loads?

I have already wondered in your original post whether you really want to carry out the renovation without accompanying expert knowledge...

Best regards from the Rhineland

Those who can read are clearly at an advantage. The elevation has long been done with the architect, building application, static and structural analysis! Currently, we are doing the interior work and my post is solely about the insulation or non-insulation of the knee wall! I just thought I would elaborate a bit to better describe the surrounding conditions