Concrete Stairs Calculator
Get accurate concrete volume calculations for your staircase project. This calculator accounts for step geometry, stringer volume, and optional landing area to give you precise material quantities including bag counts and cost estimates.
Standard: 11 inches per building code
Standard: 7 inches per building code
Minimum 3 ft for residential
A landing is a flat platform at the top or bottom of stairs
Depth from the top step to the end of the landing
Optional — for cost estimation
V = Width x Tread x Riser x 0.5
Stringer Volume:
Approximately 2 stringers at 4 in wide
Length = sqrt(Total Rise² + Total Run²)
Landing Volume:
V = Width x Landing Depth x 4 in
Total:
Cubic Yards = Total Cu Ft / 27
Add 10% for waste
Per Step: V = 4 x 0.917 x 0.583 x 0.5 = 1.07 cu ft
Total Steps: 13 x 1.07 = 13.91 cu ft
With stringers (approx. 2 cu ft) and landing (approx. 4 cu ft)
Total: approx. 19.91 cu ft
Cubic Yards: 19.91 / 27 = 0.74 cu yds
With 10% waste: 0.81 cu yds
How do I calculate concrete volume for stairs?
Calculate each step individually: volume = tread width x tread depth x riser height, but since steps are triangular when viewed from the side, use (riser x tread / 2) x step width. For a flight of stairs, calculate the landing separately and add it to the total. Most building codes require each step to have a 7-inch riser and 11-inch tread.
What are the standard concrete stair dimensions?
Standard concrete stair dimensions follow building codes: riser height of 7 inches (max 7.75 in), tread depth of 11 inches (min 10 in), and minimum stair width of 36 inches for residential (44 inches for commercial). The ratio of riser to tread should follow 2R + T = 24-25 inches for comfortable stepping.
How much concrete is needed for a typical staircase?
A standard residential staircase with 13 steps (7 in rise, 11 in tread, 3.5 ft wide) requires approximately 25-30 cubic feet of concrete, or about 1 cubic yard. Including a 3 ft x 3 ft landing adds roughly another 1/3 cubic yard. Always add 10% for waste.
Do concrete stairs need reinforcement?
Yes, concrete stairs require steel reinforcement to prevent cracking and structural failure. Typically, number 4 rebar is placed at 12-inch spacing both ways in the stair slab. The stair stringer also requires continuous reinforcement. Check local building codes for specific requirements for your project.
🔗 Related Calculators
📐 Formula
V = Width x Tread x Riser x 0.5
Stringer Volume:
Approximately 2 stringers at 4 in wide
Length = sqrt(Total Rise² + Total Run²)
Landing Volume:
V = Width x Landing Depth x 4 in
Total:
Cubic Yards = Total Cu Ft / 27
Add 10% for waste
📝 Example Calculation
Per Step: V = 4 x 0.917 x 0.583 x 0.5 = 1.07 cu ft
Total Steps: 13 x 1.07 = 13.91 cu ft
With stringers (approx. 2 cu ft) and landing (approx. 4 cu ft)
Total: approx. 19.91 cu ft
Cubic Yards: 19.91 / 27 = 0.74 cu yds
With 10% waste: 0.81 cu yds