Concrete stairs calculator
Type how many steps there are, along with the width of each step. The starting numbers are a tread of 11 in, a riser of 7 in and a landing of 36 in, so change them to match your own steps.
Concrete step calculator for 1 to 6 steps
| Steps | Total rise | Cubic yards | 80 lb bags | 60 lb bags |
|---|---|---|---|---|
| 1 | 0.58 ft | 0.37 | 17 | 23 |
| 2 | 1.17 ft | 0.83 | 38 | 50 |
| 3 | 1.75 ft | 1.38 | 63 | 83 |
| 4 | 2.33 ft | 2.01 | 91 | 121 |
| 5 | 2.92 ft | 2.73 | 123 | 164 |
| 6 | 3.5 ft | 3.54 | 160 | 213 |
This table is a reference, not your answer. It assumes a solid stair 4 ft wide with 7 in risers, 11 in treads and a 36 in top landing. Every figure includes 10% extra.
Riser and tread sizes
The International Residential Code says that at a house, risers can be no more than 7¾ in and treads need a depth of at least 10 in. Stairs also need a width of at least 36 in (IRC R311.7). The starting values of 7 and 11 in stay inside those limits.
Every step you add sits on the steps before it, so it calls for more concrete than the step before. By the sixth step, the amount of concrete is about double what the first step takes. If you need a ramp, work with the main estimator and treat it as a slab, using its average thickness.