Stair geometry
Stair geometry: use total vertical rise, maximum desired riser height, tread going. Review the formula, worked example and calculation steps.
Inputs
Use the units shown—
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Formula & explanation
Risers = ceil(total rise/max riser); actual riser = total rise/risers; run = (risers−1)×going
Variables & units
- Total vertical rise
- m · minimum 0.001, maximum 1000000000000
- Maximum desired riser height
- m · minimum 0.001, maximum 1000000000000
- Tread going
- m · minimum 0.001, maximum 1000000000000
Worked example
2.8 m total rise, maximum 0.18 m riser and 0.28 m going gives 16 risers, 0.175 m each, and 4.2 m run.
Assumptions
Simple single flight ending at a landing. Not a code-compliance check; headroom, width, nosing, handrails and landings are excluded.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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