How to use the concrete steps calculator
- Enter the number of steps (risers). Three steps up to a door means three risers, with the landing or doorway at the top.
- Enter the rise (height) and run (tread depth) of each step. Most codes allow up to about 7 3/4 inch risers and want at least 10 inch treads; 7 × 11 inches is comfortable.
- Enter the step width and, if there's a landing at the top, its depth from the door to the first step.
Concrete steps formula
Solid steps are a stack of blocks: the bottom step is one riser tall, the next is two risers tall, and so on.
steps volume = width × run × rise × (n × (n + 1) ÷ 2)
landing volume = landing depth × width × (n × rise)
cubic yards = (steps + landing) × 1.1 ÷ 27
An 80 lb bag of premix makes about 0.6 cu ft, so there are 45 bags in a cubic yard. Above about one yard, ready-mix delivery is usually easier and cheaper.
Concrete for common sets of steps
7 inch rise, 11 inch run, no landing, 10% extra.
| Steps | Width | Cu ft | Cu yd | 80 lb bags |
|---|---|---|---|---|
| 2 | 3 ft | 5.3 | 0.20 | 9 |
| 2 | 4 ft | 7.1 | 0.26 | 12 |
| 3 | 4 ft | 14.1 | 0.52 | 24 |
| 3 | 5 ft | 17.6 | 0.65 | 30 |
| 4 | 4 ft | 23.5 | 0.87 | 40 |
| 4 | 6 ft | 35.3 | 1.31 | 59 |
| 5 | 4 ft | 35.3 | 1.31 | 59 |
| 6 | 4 ft | 49.4 | 1.83 | 83 |
Building tips
- Save concrete with fill. On big steps, pack the inside with compacted gravel or broken concrete, keeping at least 4 inches of concrete on the treads and risers.
- Footings: steps against a house usually sit on a footing below the frost line, or are tied to the foundation. Check local code.
- Slope each tread about 1/8 inch toward the front so water runs off.
- Reinforce with rebar or wire mesh; the rebar calculator works out a grid for the landing.
Frequently asked questions
How much concrete do I need for 3 steps?
Three solid steps 4 ft wide with a 7 inch rise and 11 inch run take about 14.1 cubic feet (0.52 cubic yards) with 10% extra, or 24 bags of 80 lb concrete.
How many bags of concrete for steps?
Work out the volume in cubic feet and divide by 0.6 for 80 lb bags or 0.45 for 60 lb bags. Small sets of steps usually take 15 to 40 bags of 80 lb concrete.
What is the standard rise and run for concrete steps?
A rise of about 7 inches and a run of 11 inches is comfortable and meets most codes, which typically allow up to 7 3/4 inch risers and need at least 10 inch treads.
How thick should concrete steps be?
Solid steps are filled all the way through. If you use gravel fill inside, keep at least 4 inches of concrete on every tread and riser.