whori

i think you should read tutorials that comes with revit..




Creating Spiral Staircases Revit Architecture 2009 User's Guide > Working with Architectural Components > Stairs >
Creating Spiral Staircases

1. Open a plan or 3D view.
2. Click Modelling menuStairs, or on the Modelling tab of the Design Bar, click Stairs.
3. Click Set Work Plane on the Design Bar to select a different work plane. See Sketching and Work Planes.
4. On the Options bar, click .
5. In the drawing area, click to select a center point for the spiral.
6. Click a start point.
7. Click an end point to complete the spiral.
   Completed spiral staircase
   
   
   The spiral is limited to fewer than 360 degrees. If you overlap spiral runs, a warning is displayed; stringers and railings are not placed accurately.

TipTo create a spiral staircase to multiple levels, create one helix for the stairs and then copy that helix to the appropriate levels.