Dear brother, you can define it as rafter raft when in architectural mode. But when you do this, an unnecessary amount of floor reinforcement will come out, because this time the foundation is continuous foundation, while rafter raft is not saved. You will have done it and in the program you will need reinforcement and sectioning at minimum pursantages.... Do you know what Q16/15cm means for flooring, they laugh. What you need to do here is to model it as 1 layer up to the top of the basement. In the formwork plan mode, you will create the other floors just like you normally do and you will have made the foundation floor. Then you will model the other floors on top of it 1,2,3 etc. how many floors it has.. You will enter the basement floor number with a rigid top in the analysis settings (that is, if you have made the zeroth floor, you will enter the basement floor number). you will enter the floor 0 there)... my advice to you is the same as the floors on the upper floor. The floor concrete doesn't just fill the inside of the beams or curtains, it stays between the columns and the curtains and creates a weak link... Thank you.