How much concrete do I need for concrete steps?

Work the stepped section, not a length. At 7 in rise, 11 in tread and 48 in wide, a five-riser flight counted as 15 step units of 77 sq in is 1.19 cubic yards solid. Ten risers is 55 units and 4.36 cubic yards, because each step stands on every step below it. That count includes a full-height 11 in column behind the top riser; where an existing landing takes its place, the volume is lower. This is this site's arithmetic.

How tall can a concrete step be?

Not more than 7 3/4 in under IRC R311.7.5.1, measured between the leading edges of adjacent treads. The tallest and shortest riser in a flight may not differ by more than 3/8 in. On concrete that includes the bottom riser, which changes if the slab at the foot of the stair is poured to a different level than planned.

How deep should concrete stair treads be?

At least 10 in under R311.7.5.2. At 11 in or deeper, R311.7.5.3 no longer requires a nosing, which on concrete removes an undercut form from every riser at the cost of an extra inch of run per step.

Do outdoor concrete steps need a handrail?

Yes on not less than one side of each flight with four or more risers, under IRC R311.7.8. It goes 34 in to 38 in above the sloped plane adjoining the tread nosings, per R311.7.8.1.

How much do concrete steps cost?

HomeAdvisor gives $200 to $600 per step for a 4 ft wide step, $1,800 to $6,000 for poured steps as a whole job, and different ranges again in its headline and overview. The per-step figure fits a short flight better than a long one, because the concrete in a solid flight grows with the triangular number n(n+1)/2 while the per-step price stays flat. Last price check: 2026-09-13.

Should concrete steps be solid or poured over fill?

Either. A shell over compacted fill uses less concrete on a long flight, because the solid volume grows roughly with the square of the riser count. NRMCA asks for the subgrade under flatwork to be compacted uniformly with no wet spots, and none of the sources behind this page sets a separate fill specification for a stair shell.

What strength concrete for exterior steps?

IRC Table R402.2 names steps exposed to the weather directly: 2,500 psi in a negligible weathering region, 3,000 psi moderate and 3,500 psi severe. In the moderate and severe columns footnote d requires 5 to 7 percent entrained air, which the Quikrete and Sakrete bagged mix data sheets do not publish.

How to Pour Concrete Stairs

A concrete stair is the one pour where a mistake in the layout cannot be trimmed, shimmed or sanded out afterwards. The dimensions are fixed by the code before the forms go up, the concrete follows from the dimensions faster than the step count suggests, and a flat price per step does not follow it.

By Lucas Pradella, builder and editor. Checked 2026-09-16.

Measure the rise to the finished surface, not the dirt

Every stair begins with one number, the total rise, and on an exterior concrete stair it is easy to measure wrong. It runs from the top landing or door threshold down to the finished surface at the bottom: the patio, the walk or the landing pad, as it will be once it is poured.

If that bottom slab goes in after the steps, every riser in the flight is built to a surface that does not exist yet. Pour the pad an inch proud of where you guessed and the bottom riser comes out an inch short while every other riser is correct, which is more than the 3/8 in uniformity limit below allows. On timber you would recut a stringer. On concrete it means a saw or a breaker.

So the order is fixed: set the finished grade at the bottom first, or at least fix it with a string line and a stake that nobody moves, and lay out the flight from there.

What IRC R311.7 fixes before you build a form

Dwelling stairs are governed by IRC Section R311.7, read here from the 2018 Seattle Residential Code, which prints the 2018 IRC with Seattle amendments marked, and the limits that decide a concrete flight are short enough to keep on the form boards:

R311.7.5.1, risers: not more than 7 3/4 in, measured vertically between the leading edges of adjacent treads, and the tallest riser in a flight may not exceed the shortest by more than 3/8 in.
R311.7.5.2, treads: not less than 10 in, measured horizontally between the foremost projections of adjacent treads, with the same 3/8 in uniformity limit.
R311.7.5.3, nosings: a nosing projection of 3/4 in to 1 1/4 in, and none required where the tread is 11 in or deeper.
R311.7.1, width: not less than 36 in clear at all points above the permitted handrail height.
R311.7.2, headroom: not less than 6 ft 8 in, measured from the sloped line joining the nosings.
R311.7.3, vertical rise: no more than 151 in, which Seattle prints as 12 ft 7 in, in a single flight between floor levels or landings. Check the edition your jurisdiction has adopted.
R311.7.8, handrails: on not less than one side of each flight with four or more risers, at 34 in to 38 in above the sloped plane of the nosings, per R311.7.8.1.

The nosing line is the one that pays on concrete. Forming a projecting nosing on every tread means an undercut form on every riser, and an 11 in tread removes the requirement entirely, which is worth weighing against the extra inch of run on every step.

The riser count is always rounded up. Total rise divided by 7 3/4 in gives a fraction, rounding it down makes every riser taller than the code allows, and rounding up is the only legal direction.

From total rise to concrete, worked through

This site's arithmetic on R311.7: the fewest risers that keep each one at or under 7 3/4 in, treads of 11 in so no nosing is required, a 48 in wide flight poured solid, and a 10 percent allowance rounded up to the quarter yard for the order.

Riser count from R311.7.5.1 and volume from the stepped section, this site's arithmetic. Riser heights to the nearest sixteenth; run is treads times 11 in. The volume counts one 11 in column per riser, n(n+1)/2 units of riser height times 11 in, which includes a full-height 11 in column behind the top riser; where an existing landing or floor takes that place, the section is n(n-1)/2 units and the volume is lower.
Total rise	Risers	Each riser	Treads	Total run	Solid volume, cu yd	Order
18 in	3	6 in	2	1 ft 10 in	0.41	0.50
24 in	4	6 in	3	2 ft 9 in	0.68	0.75
32 in	5	6 3/8 in	4	3 ft 8 in	1.09	1.25
40 in	6	6 11/16 in	5	4 ft 7 in	1.58	1.75
48 in	7	6 7/8 in	6	5 ft 6 in	2.17	2.50
56 in	8	7 in	7	6 ft 5 in	2.85	3.25
64 in	9	7 1/8 in	8	7 ft 4 in	3.62	4.00

Two things fall out of it. The first is that the run grows in a straight line while the concrete does not. Going from 32 in of rise to 64 in doubles the run and more than triples the solid volume, because each step stands on every step below it and the section of the flight is a triangle rather than a strip.

The second is the treads column. There is always one fewer tread than riser, because the top riser lands on the landing or the floor, which does the job of the last tread. Planning the run with one tread per riser makes the flight a full tread longer than the space.

A flat price per step cannot be right, and here is the arithmetic

HomeAdvisor's concrete steps cost guide, by a HomeAdvisor staff writer edited by Ryan Noonan and published 20 June 2026, prices concrete steps two ways on the same page: $200 to $600 per step for a step 4 ft wide, and $1,800 to $6,000 for poured steps as a whole job. Its headline says $600 to $5,000 and its overview says $400 to $6,000, so the page disagrees with itself before any arithmetic starts. Last price check: 2026-09-13.

The per-step row has a deeper problem. A price per step is flat, and the concrete in a step is not: in a solid flight on this page's count the column under the top step is as many risers tall as the flight has risers, while the column under the bottom one is one riser tall. The table below puts the two side by side, with concrete priced from HomeGuide's concrete price guide, written by Tom Grupa and published 6 January 2026: $119 to $147 per cubic yard delivered plus $53 per yard under a full 10-yard load, which is $172 to $200 per yard in this site's arithmetic. Last price check: 2026-09-15.

This site's arithmetic: solid flights at 7 in rise, 11 in tread and 48 in wide, counted as n(n+1)/2 step units as in the table above; concrete at HomeGuide's $119 to $147 per yard plus $53 short-load; installed price at HomeAdvisor's $200 to $600 per 4 ft step. The share column brackets the cheapest concrete against the dearest installed price and the reverse.
Risers	Step units	Solid, cu yd	Order	Concrete delivered	Installed, per-step rate	Concrete share
3	6	0.48	0.75	$129 to $150	$600 to $1,800	7% to 25%
4	10	0.79	1.00	$172 to $200	$800 to $2,400	7% to 25%
5	15	1.19	1.50	$258 to $300	$1,000 to $3,000	9% to 30%
6	21	1.66	2.00	$344 to $400	$1,200 to $3,600	10% to 33%
8	36	2.85	3.25	$559 to $650	$1,600 to $4,800	12% to 41%
10	55	4.36	5.00	$860 to $1,000	$2,000 to $6,000	14% to 50%

Step units are the triangular number n(n+1)/2: a flight of 10 risers has 55 units of section, not 10. Double the risers from 5 to 10 and the per-step price doubles while the concrete multiplies by 3.7. At the top of the table, concrete alone can be half the installed price at the low per-step rate, which leaves very little for forms, labor and finishing.

The whole-job row does not rescue it either. At $200 to $600 per 4 ft step, $1,800 to $6,000 describes anything from 3 steps at the top rate to 30 steps at the bottom one. On this arithmetic the per-step figure fits a short flight better than a long one.

Strength and air: the row that names steps

Most exterior flatwork borrows its code benchmark from a neighboring row. Steps do not have to. IRC Table R402.2 names steps exposed to the weather directly, in the same row as porches, carport slabs and garage floor slabs: 2,500 psi where weathering potential is negligible, 3,000 psi moderate and 3,500 psi severe, with footnote d requiring 5 to 7 percent entrained air in the moderate and severe columns.

Footnote d makes that air a requirement, not a preference, in moderate and severe weathering regions. The Quikrete and Sakrete bagged mixes this site's concrete calculator carries publish 4,000 psi at 28 days and publish no air content, so where footnote d applies, a bagged stair does not evidence compliance however strong it is.

Solid or a shell, and twice the formwork of a slab

The alternative to a solid flight is a shell. A shell is the treads, risers and sides poured over compacted fill, and the triangular growth in the tables above is the case for it: the solid volume grows roughly with the square of the riser count and the shell does not.

The fill is carrying the treads. NRMCA's finishing sheet asks for the subgrade under any flatwork to be compacted uniformly, with no wet spots, and none of the sources behind this page sets a separate specification for fill under a stair shell.

Whichever you choose, the forms are a large part of the work. On the five-riser flight in the table, the vertical forms alone are the five riser boards at 7 by 48 in, 11.7 sq ft, plus two stepped side forms of 1,155 sq in each, 16.0 sq ft, for 27.7 sq ft of formwork holding 1.19 cubic yards. The same 1.19 yards poured as a square 4 in slab needs about 13.1 sq ft of edge form. That is this site's arithmetic, and it says a stair needs roughly twice the formwork of a slab for the same concrete, all of it braced against wet concrete pushing out and lifting up at once.

NRMCA's joint sheet adds one more piece: isolation joints belong where driveways and patios meet stairs, so the flight and the slab at its foot can move independently. For isolation joints the same sheet names premolded joint filler, such as asphalt-impregnated fiber sheeting or compressible foam strips.

Finishing treads is a race you cannot run in the usual order

A stair presents every tread at a different height, and all of them on the same setting clock. NRMCA's finishing rules still apply to each one:

Level before bleed water appears, keeping the float flat so the surface is not sealed early.
Wait until the bleeding has stopped and the sheen has gone. NRMCA estimates set for final finishing when a footprint leaves an indentation of 1/8 to 1/4 in.
Never sprinkle water or dry cement on the surface to make it work, which causes dusting or scaling.
Edge every nosing with an edging tool for a durable rounded arris, after breaking the bond with the form using a mason's trowel.
Broom texture the treads for a non-slip surface, and avoid steel troweling air-entrained concrete, which bleeds more slowly and delaminates or blisters if finished early.

The finishing guide covers each of those operations and the defects that follow from rushing them.

Curing, stripping and cold weather

Curing starts as soon as finishing is complete and typically runs 3 to 7 days under NRMCA's curing sheet. If you use plastic, it should meet ASTM C171, be at least 4 mils thick, sit in direct contact with the surface, and extend beyond the edge of the concrete by at least twice the slab thickness. On a stair that means it drapes down every riser. Wrinkles leave dark streaks, and the sheet says plastic should not be used where appearance is important.

Cold weather has a written definition in NRMCA's sheet: more than three consecutive days with an average daily temperature below 40°F, and air temperature not above 50°F for more than half of any 24 hours. When it applies, the recommended concrete temperature at placement for any section under 12 in thick is 55°F, fresh concrete should be protected from freezing until it reaches 500 psi, about two days, and from repeated freeze-thaw cycles until 3,500 psi. The same sheet notes that corners and edges are most susceptible to heat loss, and a flight of steps is very nearly all corners and edges.

In cold weather NRMCA leaves forms on for 1 to 7 days depending on strength gain, conditions and loading, and asks for field-cured cylinders or nondestructive testing to estimate in-place strength before stripping. Removing protection should not shock the concrete either, and in cold weather the curing sheet limits cooling to 5°F per hour for the first 24 hours.

Run the numbers

Frequently asked questions

How much concrete do I need for concrete steps?: Work the stepped section, not a length. At 7 in rise, 11 in tread and 48 in wide, a five-riser flight counted as 15 step units of 77 sq in is 1.19 cubic yards solid. Ten risers is 55 units and 4.36 cubic yards, because each step stands on every step below it. That count includes a full-height 11 in column behind the top riser; where an existing landing takes its place, the volume is lower. This is this site's arithmetic.
How tall can a concrete step be?: Not more than 7 3/4 in under IRC R311.7.5.1, measured between the leading edges of adjacent treads. The tallest and shortest riser in a flight may not differ by more than 3/8 in. On concrete that includes the bottom riser, which changes if the slab at the foot of the stair is poured to a different level than planned.
How deep should concrete stair treads be?: At least 10 in under R311.7.5.2. At 11 in or deeper, R311.7.5.3 no longer requires a nosing, which on concrete removes an undercut form from every riser at the cost of an extra inch of run per step.
Do outdoor concrete steps need a handrail?: Yes on not less than one side of each flight with four or more risers, under IRC R311.7.8. It goes 34 in to 38 in above the sloped plane adjoining the tread nosings, per R311.7.8.1.
How much do concrete steps cost?: HomeAdvisor gives $200 to $600 per step for a 4 ft wide step, $1,800 to $6,000 for poured steps as a whole job, and different ranges again in its headline and overview. The per-step figure fits a short flight better than a long one, because the concrete in a solid flight grows with the triangular number n(n+1)/2 while the per-step price stays flat. Last price check: 2026-09-13.
Should concrete steps be solid or poured over fill?: Either. A shell over compacted fill uses less concrete on a long flight, because the solid volume grows roughly with the square of the riser count. NRMCA asks for the subgrade under flatwork to be compacted uniformly with no wet spots, and none of the sources behind this page sets a separate fill specification for a stair shell.
How long before I can strip the forms on concrete steps?: NRMCA's cold weather sheet gives 1 to 7 days for form removal in cold weather, depending on strength gain, ambient conditions and the loads expected, with field-cured cylinders or nondestructive testing to estimate strength first. Its curing sheet says curing typically runs 3 to 7 days, and in cold weather limits cooling to 5°F per hour for the first 24 hours.
What strength concrete for exterior steps?: IRC Table R402.2 names steps exposed to the weather directly: 2,500 psi in a negligible weathering region, 3,000 psi moderate and 3,500 psi severe. In the moderate and severe columns footnote d requires 5 to 7 percent entrained air, which the Quikrete and Sakrete bagged mix data sheets do not publish.

Check these numbers yourself

2018 Seattle Residential Code, Chapter 3 Building Planning, Section R311.7Seattle Department of Construction and Inspections. Prints 2018 IRC Section R311.7: R311.7.1 width, R311.7.2 headroom, R311.7.3 vertical rise of 151 in (amended in Seattle to 12 ft 7 in), R311.7.5.1 risers and the 3/8 in uniformity limit, R311.7.5.2 treads, R311.7.5.3 nosings and the 11 in exception, and R311.7.8 handrails. Read 2026-09-16.
2018 Seattle Residential Code, Chapter 4 FoundationsSeattle Department of Construction and Inspections. Read 2026-09-09. Source of Table R402.2, whose exterior flatwork row names steps directly rather than by analogy, and of footnote d on air entrainment.
HomeAdvisor, how much do concrete steps costWritten by HomeAdvisor staff writer, edited by Ryan Noonan, published 20 June 2026, read 2026-09-13. $200 to $600 per 4 ft wide step, $1,800 to $6,000 for poured steps as a whole job. The same page gives $600 to $5,000 in its headline and $400 to $6,000 in its overview.
HomeGuide, how much does concrete cost per yardWritten by Tom Grupa, published 6 January 2026. Ready-mix $119 to $147 per cubic yard delivered, plus $53 per yard under a full 10-yard load. Read 2026-09-15.
NRMCA CIP 6, Joints in Concrete Slabs on GradeNational Ready Mixed Concrete Association. Isolation joints separate driveways and patios from stairs and other points of restraint, with premolded joint filler named for isolation joints. Read 2026-09-16.
NRMCA CIP 11, Curing In-Place ConcreteNational Ready Mixed Concrete Association. Curing for 3 to 7 days; plastic to ASTM C171 at least 4 mils, in contact with the surface and extending beyond the edge by twice the slab thickness; cooling limited to 5°F per hour in the first 24 hours. Read 2026-09-16.
NRMCA CIP 14, Finishing Concrete FlatworkNational Ready Mixed Concrete Association. Subgrade compacted uniformly with no wet spots; level before bleed water, wait for bleeding to stop, footprint indentation of 1/8 to 1/4 in for final finishing, never sprinkle water or cement, edge and broom exterior surfaces, caution on steel troweling air-entrained concrete. Read 2026-09-16.
NRMCA CIP 27, Cold Weather ConcretingNational Ready Mixed Concrete Association. Cold weather definition; 55°F placement temperature for sections under 12 in; protect from freezing to 500 psi, about two days, and from freeze-thaw cycles to 3,500 psi; corners and edges most susceptible to heat loss; forms left 1 to 7 days. Read 2026-09-16.

Figures here last checked against the source documents on 2026-09-16. Codes are amended locally; confirm against the edition your jurisdiction enforces.

About the author

Lucas Pradella builds and maintains Nails & Numbers. He is not a tradesperson: every figure on the site is traced to a named, dated document, and the page links it so you can check it yourself. More about how these pages are made.

Every guide on this site: Guides.