What size for my T30 raw wall?

Your screed (Not: dining table) is more than 18 mm. Definitely. Especially with tiles. Even the thinnest possible (screed asphalt) must be at least 25 mm!

That is 18 cm (16.5 cm plus 15 mm tiles and adhesive) from the raw floor, of which 5 or 6 cm is screed, the rest insulation.

Otherwise, just let the architect handle it, after all, you have one for that. If it starts off like this, you might easily have a heart attack during construction ops: ops:

Your screed (not: dining table) is more than 18 mm. Definitely. Especially with tiles. Even the thinnest possible (screed made of bituminous asphalt) must be at least 25 mm!

That’s 18 cm (16.5 cm plus 15 mm tiles and adhesive) from the raw floor, of which 5 or 6 cm is screed, the rest insulation.

Otherwise, just let the architect do it, that’s what you have one for. If it already starts like this, you might easily have a heart attack during construction ops: ops:

Hi Scout,
Thanks for your answer.
Dining table was an autocorrect mistake. My phone doesn’t know the word screed :d
And you’re right. My screed is more than 18 mm. It’s a total of 18 cm (as you wrote).
I wasn’t completely satisfied with my architect. Unfortunately, we are building with a general contractor. The architectural service is included in the package. Back then I decided on the T30 for self-performance because of about 1000€ difference. I didn’t expect the consequences.