Thank you both,

hansmex, ok, I'm sorry, I don't post translation (I did not know)

puybaret, I knew this solution for a second plant (so I do now), but thanks.

Both,
Anyway, it was just an idea, and I imagine there are much better solutions (of course).

I look forward to this new version with ...

I hope you understand what I mean.

I mean, no need to create a structure called "floor". Simply change this parameter to a wall made of floor.

My English is not very good, but I hope you understand me.

I want to propose interesting something from the standpoint of development.

I love Sweet Home 3D but it has an inconvenience: make the second floor, but I think that it is very easy to change this.

Developers should have to allow ...