information in this article applies to:
How do I create a set of winder stairs?
Stair winders can be created using a variety of different methods, which include:
Winders created using the Stair Specification dialog must be created in a room with proper room definition.
You cannot create winders using this method in an area composed of only 2 corner walls. If this configuration is needed, enclose the area in with invisible walls so that a room area is defined.
Alternatively, Right click and drag will enable this alternate drawing mode as well.
Winders that are created automatically using the L-Shaped and U-Shaped stair tools are converted to landings and can be modified further to your liking.