Insulate concrete ceiling upper floor

I once calculated with the new proposed construction using the 16cm Styrofoam boards EPS 035 in the U-value calculator:

0.19 is not eligible for funding! So a) worse insulation and b) not €500 cheaper, but only €60 (€2,200 minus 20% funding = €1,760) The answer to your question then follows by itself.

Yes, you are right. Then it is pointless. Thx!!!

How much waste should I account for? Is 5% additional material enough?

thx

One more thing about the weak point: the hatch of the attic ladder! Are there any other alternatives instead of buying a new insulated model? Any ideas?

What other alternatives are there, if any, instead of buying a new insulated model? Any ideas?

Sorry, I'm out on this topic. I haven't dealt with it yet. But as far as I know, it is also subsidized.

Is that too expensive for you?

I have a question that has been bothering me for a while. To make my attic accessible, I mixed ClimaWool with EPS. The EPS "ridges" serve as a support surface for the OSB boards. Is the mix of the different materials a problem? Here is an old photo: