Stair type overview
Spiral Stairs
20 in usable width, 80 in headroom. Spiral stairs are the most restrictive common stair type for furniture moves.
curvedcomplex navigation
Typical Stair Measurements
Clear width
24"
Effective width
20"
Tread depth
9"
Riser height
9"
Headroom
80"
Diameter
60"
These are planning defaults. Measure your real stairway before buying, moving, or booking delivery.
Fit Notes
- The center pole and inner radius sharply reduce usable width.
- Large rigid furniture rarely has room to rotate continuously.
- Measure effective walking width at the walking line, not the outer diameter.
What Fits?
Small boxed chair
Works only if the box stays within the effective walking width.
Foam mattress
May work if flexible and carried vertically.
3-seat couch
Length and pivot clearance usually fail.
Upright piano
Weight, balance, and landing turns usually require professional movers or another route.
Check Your Specific Item
Enter your item dimensions and staircase details to test the exact width, turn, landing, and headroom constraints.
Open Stair Fit Calculator
