Every step, considered.
Find the right proportions. See the design take shape.
Design inputs
Design standard / project limits
Original ergonomic references; no national code certification.
Limit plan dimensions
Width and length follow the drawing axes. Reserve clearance separately.
Preliminary construction details
These are user-specified drawing dimensions, not structural design results. Beam/slab sizing and reinforcement require loads, spans, supports, materials and the applicable design code.
Headroom settings
Distance to the slab opening, measured along the stair run.
Recommended solutions
Optimize scheme
Searches 15–25 risers and 240–340 mm treads. Plan limits and ergonomic criteria are checked before preferences.
20 risers · T 295.0 mm
2R + T = 625.0 mm · 29.2°
5,605 × 1,000 mm
| N | R (mm) | 2R + T (mm) | α | Rating |
|---|---|---|---|---|
| 220.0 | 720.0 | 38.2° | STEEP | |
| 206.3 | 692.5 | 36.4° | POOR | |
| 194.1 | 668.2 | 34.7° | POOR | |
| 183.3 | 646.7 | 33.2° | POOR | |
| 173.7 | 627.4 | 31.8° | IDEAL | |
| 165.0 | 610.0 | 30.5° | GOOD | |
| 157.1 | 594.3 | 29.3° | POOR | |
| 150.0 | 580.0 | 28.2° | POOR | |
| 143.5 | 567.0 | 27.1° | POOR | |
| 137.5 | 555.0 | 26.2° | POOR | |
| 132.0 | 544.0 | 25.2° | POOR |
Live blueprint
Stair geometry
- Plan envelope
- 5,040 × 1,000 mm
- Riser split by flight / turn
- 19
- Minimum tread at walkline
- 280.0 mm
- Waist slab thickness / Landing slab thickness
- 150 / 150 mm
- Stair beam width × Stair beam depth
- 200 × 350 mm
- Handrail height
- 900 mm
These are user-specified drawing dimensions, not structural design results. Beam/slab sizing and reinforcement require loads, spans, supports, materials and the applicable design code.
19 risers
18 treads
Standard
Ergonomic analysis
Ideal proportion
Target ≈ 450 mm
Target ≈ 120 mm
Meets 2,000 mm reference
Geometry and ergonomic checks support preliminary design. Verify local code, landings, handrails, and project conditions.
Material quantities · preliminary BOQ
Quantity assumptions
The default 100 kg/m³ is an editable budgeting assumption, not a code-prescribed steel ratio or structural design.
Additional beam quantities are entered separately. Use the beam width/depth in construction details for concrete/timber; avoid counting overlapping concrete twice.
| Item | Net quantity | With allowance +5% |
|---|---|---|
| Waist slab concrete | 0.89 m³ | 0.934 m³ |
| Step wedges concrete | 0.438 m³ | 0.46 m³ |
| Landing concrete | 0 m³ | 0 m³ |
| Additional beam concrete | 0 m³ | 0 m³ |
| Total modeled concrete | 1.327 m³ | 1.394 m³ |
| Estimated reinforcement | 132.732 kg | 139.368 kg |
Preliminary quantities for the modeled stair only. Excludes floor slabs, supports, guardrails, connections, finishes and foundations. Sizes/rates are user inputs; reinforcement is not a bar-bending schedule. Piece allowances round up.
BOQ quantities stay in m³, m², m and kg when drawing units change.
Guides & Design Standards
Learn how to calculate stair risers, check the Blondel formula, compare layouts and estimate concrete, steel or timber quantities.
Read the full guide