I think you are right. This is what I obtained following your suggestion:I usually place the spiral staircases next to a wall. this wall partially replaces the handrail.
I love open constructions and therefore staircases without railing or handrail. but in real I would of course also install a bit more security, but not 50cm stone walls, but 25mm wood walls.
P.S. Thank you both for telling me how to import staircases in the right way
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