Basic Stairs between the building stories

The Stair systems in Archicad is a System tool: it is a hybrid mixture of a library object to manage components and profiles and a modeling tool to allow broad geometric flexibility. You define a Stair using its main reference line (called the Baseline), just as with Walls or Beams, and can link the bottom and top to stories, but you also have a contour to control the outline, just as with Slabs or Roofs. The Baseline contains multiple segments, which can each be set to become a Flight, Landing, or Winder part, and you have deep control over how the Stair, including Landings and Treads and Railings, will be generated from its Baseline and contour.

Let’s dive in with a basic setup for a straight Stair:

1. Activate the Stair command from the Tool Box.
2. Set the Baseline position to the Right side of the Stair, but keep Offset at 0.
3. Pick the first Baseline node in the 2D Window and start moving to the right.
4. Archicad shows...