Concrete Steps Volume
Count risers, not treads. Add a landing in the options.
Concrete
Concrete Steps Calculator
Quick answer: solid step volume = width × run × rise × (1 + 2 + … + n). Three 48 in wide steps with 7 in risers and 11 in treads need 12.8 ft³ (0.48 yd³); a 36 in landing on top brings it to 1.38 yd³ with 10% waste — about 63 bags of 80 lb mix.
Estimate concrete for solid poured steps and stoops, including an optional landing at the top. Get cubic yards, bag counts, and a cost comparison between bagged mix and ready-mix.
Stacked-block step model
How to calculate concrete for steps
Think of a solid flight of steps as a row of blocks standing side by side. The first block is one riser tall, the second is two risers tall, and so on up to the top step. Each block is one tread deep and the full stair width. Adding them up gives the volume of the whole flight.
W × run × rise × n(n + 1) ÷ 2
+ W × landing depth × (n × rise) = cubic feet (dimensions in feet); ÷ 27 for cubic yards
- Count the risers. A stoop that climbs 21 in to a door with 7 in risers has 3 risers. Enter that number as the steps.
- Convert rise, run, and width to feet (divide inches by 12).
- Add the step blocks: width × run × rise × (1 + 2 + … + n). The sum 1 + 2 + … + n equals n(n + 1) ÷ 2, which is 6 for three steps and 10 for four.
- Add the landing, if any: width × landing depth × full stair height.
- Add waste (10% is typical for formed steps), divide by 27 for cubic yards, or by the bag yield for bags.
Worked example
A front stoop has 3 risers of 7 in, 11 in treads, a 48 in width, and a 36 in deep landing at the door.
- Steps: 4 ft × 0.917 ft × 0.583 ft × 6 = 12.83 ft³
- Landing: 4 ft × 3 ft × 1.75 ft (3 × 7 in) = 21.00 ft³
- Total 33.83 ft³ + 10% waste = 37.22 ft³ = 1.38 yd³
- Bags: 37.22 ÷ 0.60 = 63 bags of 80 lb mix (about $410 at $6.50), versus about $227 of ready-mix at $165/yd³ before any short-load fee
Concrete for solid steps, 48 in wide
7 in risers and 11 in treads, no landing, no waste. Multiply by your width ÷ 4 ft for other widths.
| Steps (risers) | Total rise | ft³ | yd³ | 80 lb bags |
|---|---|---|---|---|
| 2 | 14 in | 6.4 | 0.24 | 11 |
| 3 | 21 in | 12.8 | 0.48 | 22 |
| 4 | 28 in | 21.4 | 0.79 | 36 |
| 5 | 35 in | 32.1 | 1.19 | 54 |
| 6 | 42 in | 44.9 | 1.66 | 75 |
Step design and pouring tips
- Check the code dimensions first. IRC R311.7.5 sets a 7¾ in maximum riser and a 10 in minimum tread for residential stairs, with no more than ⅜ in variation between the largest and smallest riser or tread in a flight.
- Divide the total rise evenly. Measure from the landing surface or door sill down to finished grade, then divide by the number of risers. 21 in ÷ 3 = 7 in; 24 in ÷ 3 = 8 in, which is too tall, so use 4 risers of 6 in.
- Plan a landing at doors. The IRC requires a landing outside exterior doors at least 36 in deep in the direction of travel. Enter it as the landing depth so it is included in the pour.
- Handrails start at four risers. Under the IRC, a flight with four or more risers needs a handrail on at least one side. Set anchors or sleeves before the pour if you will post-mount it.
- Slope treads slightly for drainage. About ⅛ to ¼ in per foot toward the front edge keeps water and ice off the treads.
- Brace the riser forms. A 48 in wide form board holding 7 in of wet concrete will bow without stakes or cleats; a bowed riser leaves an uneven step and spills concrete.
Concrete steps FAQ
How much concrete do I need for steps?
Each step is a block as tall as all the risers below it, so volume = width × run × rise × (1 + 2 + … + n). Three steps 48 in wide with 7 in risers and 11 in treads hold 12.8 cu ft, or 0.48 cubic yards, before waste.
How many bags of concrete for 3 steps?
Three solid steps 4 ft wide with 7 in risers and 11 in treads need about 12.8 cu ft of concrete. That is 22 bags of 80 lb mix (0.60 cu ft each), or 24 bags with 10 percent waste. A 36 in deep landing at the top adds another 21 cu ft.
What is the code for concrete step height and depth?
The International Residential Code (R311.7.5) limits risers to 7¾ in maximum and requires treads of at least 10 in. Within one flight, the tallest riser and the deepest tread may not exceed the smallest by more than ⅜ in. Your local building department may adopt amendments, so confirm before forming.
Can you fill concrete steps with gravel to save concrete?
Yes. Large stoops are often built with compacted gravel or clean fill inside the forms and a concrete shell about 4 to 6 in thick over it. This calculator assumes solid concrete, so it gives the maximum quantity; a filled stoop needs less.
How thick should the bottom of concrete steps be?
The lowest step should sit on a compacted base and, where frost is a concern, be tied to footings or the foundation so it does not heave. Steps poured against a house are often doweled into the foundation wall with rebar. Check local code for frost and footing requirements.
How we built this calculator: results use the standard volume, area, and coverage formulas shown on this page, with typical U.S. material densities, bag yields, and waste factors that you can override. Written and checked by the YardsCalculator editorial team. Last reviewed: October 2026.