How to make a section of circular stairs open underneath?

[ddaigle]

I'm working on plan with a circular staircase going up to the second floor.
I'm wanting half of it open underneath as there will be a passageway underneath the stairs into another room.
I've tried creating the stairs in sections with one section being 'open underneath', but as soon as I connect the stairs, they all have the same property (closed).

Is there a way around this this? Or a different solution?

Any help is appreciated.

[dshall]

The closed underneath option should be used with discretion. have the stairs open underneath and put in your own walls where you want them.

[ddaigle]

Thanks for the tip dshall (btw ... I've learned a lot from your videos!!).
I think I've figured out a work-around. I interrupted my curved staircase with a a tiny landing that looks like a stair. This allowed me to break up the definitions.