Spiral Staircase Calculator (Rotating / Round / Screw)
Build a spiral staircase with our free calculator — simple design round stairs in inch and metric units with detailed drawings, adaptive 3D.
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Calculation results
Staircase Dimensions
- Angle: 24.38 °
- Comfortable Staircase Formula (R + G): 49.4 cm
- Blondel's Formula (2R + G): 69.4 cm
- Rise: 20 cm
- Tread Depth: 49.47 cm
- Going: 29.4 cm
- Rotation Angle: 360 °
- Number of Steps: 15 pcs.
- Stair Width: 95 cm
- Minimum Headroom: 200 cm
Materials for construction
Steps
- Tread Depth: 49.47 cm
- Length: 109 cm
- Thickness: 2 cm
- Quantity: 15 pcs.
- Wood Volume: 0.213 m3
Metal Rod
- Diameter: 10 cm
- Length: 300 cm
Initial parameters
Display
- Units: cm
- Color drawing: color
Staircase Type
- Left Turn: selected
Staircase Dimensions
- Total Rise: 300 cm
- Staircase Diameter: 200 cm
- Angle: 360 degree
Steps
- Quantity: 15 cm
- Thickness: 2 cm
- Tread Radius Around the Central Column: 4 cm
Center Column
- Diameter: 10 cm
Upper Floor Slab
- Thickness: 20 cm
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