Concrete Stair Volume Calculator
Estimate stair-flight concrete using step count, riser, tread, width, landing volume, and allowance.
Editorial review: 2026-09-29 · How we review technical content
Key takeaways
- Estimate the stepped concrete volume of a simple solid stair flight and optional landing.
- Real stair geometry can include sloped waist slabs, voids, foundations, nosings, landings, or reinforcement details that require separate takeoff.
Concrete Stair Volume Calculator
Estimate the stepped concrete volume of a simple solid stair flight and optional landing.
What this calculator does
Estimate the stepped concrete volume of a simple solid stair flight and optional landing.
The tool sums each stair prism based on cumulative riser height and adds a landing slab when a landing length is entered.
How to use the result
Real stair geometry can include sloped waist slabs, voids, foundations, nosings, landings, or reinforcement details that require separate takeoff.
How this calculator works
The stair model treats the flight as a stack of solid rectangular step prisms and optionally adds a rectangular landing.
This is appropriate for solid stepped concrete, not for a sloped waist slab or precast stair. Stair geometry is life-safety related; riser/tread dimensions and landings must follow the governing design/code.
Input checklist
- Number of risers: Enter the project-specific number of risers in count.
- Riser height: Enter the project-specific riser height in in.
- Tread depth: Enter the project-specific tread depth in in.
- Stair width: Enter the project-specific stair width in ft.
- Landing length: Enter the project-specific landing length in ft.
- Landing thickness: Enter the project-specific landing thickness in in.
- Allowance: Enter the project-specific allowance in %.
Worked example
For a simple five-riser solid stair, each successive tread contains more concrete because its supporting prism extends to a greater height.
Field checklist
- Verify whether the stair is solid or supported on a sloped waist slab.
- Measure landings separately.
- Use structural drawings for reinforcement and support.
References & further reading
- ACI SPEC-301-20 — Specifications for Concrete Construction — Reference specification used when incorporated into project specifications.
- NRMCA Concrete In Practice (CIP) — Industry education covering common concrete field problems and practices.