Cannot create 360° spiral staircase

eidam655 · ‎2025-06-04

Hi!
I am trying to create a spiral staircase that ends on the same line as it begins (so a full 360° circle).

However, even though my Archicad draws the preview successfully, it doesn't create any geometry.

Is there no way of doing this as one object? Does Archicad read the same start and end vertex as overlapping?

Thanks for any answers!

Operating system used: Windows 11 24H2

ArchiCAD 28 | Win 11
i5-12500H | RTX 4060 8GB | 32GB RAM

runxel · ‎2025-06-04

You'll probably need to fake it, being 359,99°.

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eidam655 · ‎2025-06-05

it's crazy to me that architecture should suffer from a software limitation

ArchiCAD 28 | Win 11
i5-12500H | RTX 4060 8GB | 32GB RAM

cuba · ‎2025-06-05

There are some library objects for spiral stairs..

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danielk · ‎2025-06-09

Yeah, this has always been a limitation: the stair tool geometry simply cannot overlap itself in plan. That is just how it was designed. 😕

But Architecture doesn't need to suffer for it, only the Architect. Here is how to do it (you practically have to use 2 stairs):
https://support.graphisoft.com/hc/en-us/articles/27687009124881-How-to-create-spiral-Stairs

But like @runxel suggested, I would also just make it 359.99 degrees. You will not see the difference really.

jl_lt · ‎2025-06-10

and boy, does he suffereth, that is, the architect

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