Sketch a Custom Stair for Non-Standard Geometry

1. Try the Run tool first — sketching is for geometry the standard runs (straight, spiral, winder) genuinely cannot make: fan-shaped entries, treads following a curved wall, irregular plan cuts.
2. Open the Floor Plan of the base level and start the stair:
   1. On the Architecture tab, click Stair.
   2. In Properties, set Base Level, Top Level, and Desired Number of Risers exactly as for a run-based stair — the sketch must still satisfy them.
3. Switch to sketch mode:
   1. On the ribbon, open the Run drop-down and choose Create Sketch.
   2. Revit now shows three line modes on the Draw panel: Boundary, Riser, and Stair Path.
4. Draw the two Boundary lines (green):
   • These are the sides of the stair — lines, arcs, or splines.
   • They must not cross each other, and they must not connect to each other at the ends.
5. Draw the Riser lines (black):
   • Each riser line must reach from one boundary to the other.
   • Place exactly as many risers as Desired Number of Risers demands — the counter on screen tracks created vs remaining.
   • Risers may be curved or angled; spacing them unevenly is what creates fanned/tapered treads.
6. Draw the Stair Path (the walk line with the up-arrow); Revit proposes one automatically — redraw it if the direction of travel is wrong.
7. Click ✓ (Finish Edit Mode) twice — once for the sketch, once for the stair assembly.
8. Fix common errors Revit reports:
   • "Boundary lines must not intersect": trim crossing ends with Trim/Extend (TR).
   • Wrong riser count: add/delete riser lines until 0 remaining.
9. To convert an existing standard run into an editable sketch later: select the stair, click Edit Stairs, select the run, click Convert, then Edit Sketch — this is one-way, the run loses its parametric shape handles.

Note: A sketched stair trades parametric flexibility for geometric freedom — Revit no longer reshapes it when the plan changes, so lock the design in plan before you sketch, and keep run-based stairs everywhere a standard shape works.

Taught in

• New for 2026 — first taught in BIM + Computational Workflow 2026.