ᐅ Placement of a landing step on a 90° spiral staircase

Created on: 17 Sep 2023 22:00
M
Mal Bauen
M
Mal Bauen
17 Sep 2023 22:00
For our planned stairway between floors, we are currently looking for a compromise between walkability and space requirements.
Due to limitations in the x and y directions, the step edge ends up exactly on the symmetry axis of the 90° turn (with a shift of 4 steps before and after).

As a result, the winder step, which on many stairs is exactly symmetrical in the turn—meaning it is framed by both wall stringers—“disappears.” Compared to our design, the steps are effectively shifted by half a tread width.

Can anyone explain the rationale behind this approach for the winder step? Is it purely aesthetic? Or are stairs with a symmetrical winder step (perceived or actual) easier to walk on? I can’t see why that would be the case.

A few details about our staircase:
Floor-to-floor height: 325cm (10 ft 8 in)
Number of risers: 18
Tread depth: 26.9cm (10.6 inches)
Riser height: 18.06cm (7.1 inches)
Width: 183cm (6 ft)
Length: 370cm (12 ft 2 in)
Type: Concrete staircase, folded plate design

3D-Modell einer modernen Holztreppe mit Glasgeländer in einem zweigeschossigen Gebäude
11ant18 Sep 2023 14:51
Mal Bauen schrieb:

Regarding our planned staircase between floors

in https://www.hausbau-forum.de/threads/grundriss-neubau-auf-bungalow-bestandskeller-1-5-geschossige.44686/ – which you were also welcome to link yourself...
Mal Bauen schrieb:

This eliminates the “spindle step,”

… a term that is not commonly known outside specialist trades. I had to look it up myself, as it is not dance instructors or choreographers but rather stair builders who learn this term during their training. I’m not a “neurotypical” person and am comfortable with numbers, but I don’t know anyone who thinks about such specific details when using stairs. As a building consultant with over forty years of experience in residential construction, I have never come across this term before. I find it hard to believe that your staircase would be the first to have this so-called “chromosomal defect.”
https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/
M
Mal Bauen
19 Sep 2023 23:01
Thank you. The only practical "benefit" of a symmetrical winder step that comes to mind would be more surface area in the corner for flower vases or similar items.
So this winder step requirement moves down the priority list in the staircase specifications for now...