Stair stringers for a 2.7 m floor-to-floor rise
A 2.7 m floor-to-floor rise with a 190 mm maximum riser needs 15 risers of 180 millimetres and 14 treads. With 260 millimetre goings the total run is 3.64 metres and each stringer is about 4.53 metres long.
How to work it out
- 270 cm ÷ 19 cm max = 14.21 → round up to 15 risers, each 270 cm ÷ 15 = 180 mm
- 14 treads × 260 mm = 3640 mm run · √(270² + 364²) = 4532 mm along the slope
- Comfort check: 2 × 180 mm + 260 mm = 62 cm (61–66 cm is comfortable) · stair angle 34.7 degrees
- Throat: 285 mm board − 148 mm notch depth = 137 mm
- Tread board: 260 mm tread + 19 mm nosing + 0 mm riser board = 279 mm
- Top level cut: 180 mm riser + 32 mm tread − 0 mm top finish = 212 mm below the upper subfloor
Metric stair rules vary by country: in England, for example, private stairs allow risers up to 220 mm and a pitch up to 42°, while many European codes are stricter. A 180 mm rise with a 260 mm going is a comfortable, widely acceptable combination — but confirm with your local regulations.
Adjust for your project
More options: Max riser · Spacing · Stringer board …
- Steps to cut
- 14 steps to cut in each stringer + the upper floor is the top step
- Total run (how far the stairs reach out)
- 364 cm (3.64 m)
- Stringer length (along the slope)
- 453 cm (4.53 m)
- Stringers needed
- 4 stringers
- Stringer stock to buy
- 4 × at least 5.1 m of 285 mm deep stock
- Tread board depth to buy (tread + nosing + riser board)
- 279 mm
- Drop the stringer (trim off the bottom)
- 32 mm
- Top level cut, measured down from the top surface
- 212 mm
- Wood left below the notches (throat)
- 137 mm
| Item | What to buy | Notes |
|---|---|---|
| Stringers | 4 × at least 5.1 m of 285 mm deep stock | Straight boards with no big knots along the bottom edge, where the wood is in tension. |
| Treads | 14 treads, each 1000 mm long × 279 mm deep | Depth = tread + nosing + riser board. |
| Hardware | Hangers or a hanger board at the top, fastened to the header or rim; screws for the treads and risers | Plus a handrail on at least one side — four or more risers (2021 IRC R311.7.8). |
Where to mark each step (height above the bottom)
| Step | Height above the bottom | Guard on open sides? |
|---|---|---|
| Tread 1 | 180 mm | — |
| Tread 2 | 360 mm | — |
| Tread 3 | 540 mm | — |
| Tread 4 | 720 mm | — |
| Tread 5 | 900 mm | Yes — over 30 in |
| Tread 6 | 1080 mm | Yes — over 30 in |
| Tread 7 | 1260 mm | Yes — over 30 in |
| Tread 8 | 1440 mm | Yes — over 30 in |
| Tread 9 | 1620 mm | Yes — over 30 in |
| Tread 10 | 1800 mm | Yes — over 30 in |
| Tread 11 | 1980 mm | Yes — over 30 in |
| Tread 12 | 2160 mm | Yes — over 30 in |
| Tread 13 | 2340 mm | Yes — over 30 in |
| Tread 14 | 2520 mm | Yes — over 30 in |
| Upper floor | 2700 mm | Yes — over 30 in |
One step fewer or more
| Risers | Each step | Treads | Tread depth | Total run | Check |
|---|---|---|---|---|---|
| 14 risers | 193 mm | 13 | 260 mm | 3380 mm | Risers too tall |
| 15 risers (shown) | 180 mm | 14 | 260 mm | 3640 mm | OK |
| 16 risers | 169 mm | 15 | 260 mm | 3900 mm | OK |
- Stair guard required from tread 5: it sits more than 30 in above the bottom, so open sides need a guard at least 34 in high (IRC R312.1.1, R312.1.2). This assumes the floor beside the stair is level with the bottom landing — measure where it falls away.
- Headroom: keep at least 6 ft 8 in clear above the line of the nosings along the whole flight (IRC R311.7.2). Enter the upper floor thickness to get the shortest ceiling opening.
- Leave a landing at the bottom (and the top, unless it is the floor itself) at least 36 in deep and as wide as the stair (IRC R311.7.6).
- Trim 32 mm off the bottom of each stringer (one tread thickness) so the first step comes out the same 180 mm as the rest.
Run and stringer for a 2.7 m rise, by going
| Going | Total run (how far the stairs reach out) | Stringer length (along the slope) | Tread board depth to buy (tread + nosing + riser board) |
|---|---|---|---|
| 24 cm | 336 cm | 431 cm | 259 mm |
| 25 cm | 350 cm | 442 cm | 269 mm |
| 26 cm | 364 cm | 453 cm | 279 mm |
| 28 cm | 392 cm | 476 cm | 299 mm |
| 30 cm | 420 cm | 499 cm | 319 mm |
What to know about a 2.7 m stair
“Going” is the metric word for tread depth: the level distance from one nosing to the next. A 180 mm rise with a 260 mm going gives 2 × rise + going = 620 mm, about 24.4 in, inside the 24–26 in comfort range this calculator checks. For comparison with the US code, 180 mm is about 7.1 in (the IRC limit is 7¾ in), 260 mm is about 10.2 in (IRC minimum 10 in), and 2.7 m is well under the IRC’s 12 ft 7 in (3.84 m) maximum rise for a single flight.
Each stringer is about 4.53 m along the slope, and the stock line asks for at least 5.1 m of 285 mm deep timber. That is longer than the lengths many timber merchants keep in stock, so check before you plan around one piece. The throat left below the notches is about 137 mm, and the drop — the tread thickness trimmed off the bottom — is 32 mm for the default treads.
The going is 3.64 m for 14 treads. Add room to step on at the bottom and off at the top, and check headroom along the whole flight. If the stairwell opening is shorter, a quarter landing splits the flight into two shorter runs that turn 90°.
Stair stringers for a 9 ft rise is almost the same job in inches (108 in is about 2.74 m), and Stair stringers for an 8 ft rise shows a basement flight.
Different size? Use the full Stair Stringer Calculator.
What you’ll need
- Framing squareBudget price
The tool for laying out stair stringers and rafters: rise on one leg, run on the other.
See options on Amazon (opens in a new tab) - Stair gaugesBudget price
Small brass or steel buttons that clamp to a framing square so every rise and run you mark is identical.
See options on Amazon (opens in a new tab) - Circular saw (7¼ in)Mid-range price
The most versatile first power saw: crosscuts framing lumber, rips boards and, with a straightedge, breaks down plywood sheets.
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As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
How many risers for a 2.7 m stair with a 220 mm maximum rise?
13 risers of 208 millimetres and 12 treads — two fewer steps than at 190 mm, but a steeper stair. Check that the pitch stays within your local limit.
How long is the stringer for a 2.7 m rise with 280 mm goings?
About 476 cm along the slope, with 392 cm of total going, at an angle of 32.7 degrees.
Other common sizes
- How many steps for a 3 ft deck — 5 risers
- How many steps for a 2 ft deck — 4 risers
- How many steps for a 30 in deck — 4 risers
- How many steps for a 4 ft deck — 7 risers
- Stair stringers for an 8 ft rise — 13 risers
Sources
- International Code Council, 2021 International Residential Code, Chapter 3 Building Planning (opens in a new tab) — R311.7.1 width (36 in), R311.7.2 headroom (6 ft 8 in), R311.7.3 vertical rise of a flight (12 ft 7 in), R311.7.5.1 risers (7¾ in; open risers more than 30 in up must not pass a 4 in sphere), R311.7.5.2 treads (10 in), R311.7.5.3 nosings (¾–1¼ in unless the tread is 11 in or deeper), R311.7.6 landings (36 in deep), R311.7.8 handrails, R312.1 guards.
- American Wood Council, DCA 6 Prescriptive Residential Wood Deck Construction Guide (2015 IRC edition) (opens in a new tab) — Stair requirements, Figures 28, 29, 31 and 34: 2×12 minimum stringers; cut stringers span no more than 6 ft 0 in and keep at least 5 in below the notches; at least three cut stringers at no more than 18 in on center; sloped hangers or a hanger board at the top; an intermediate landing where the total rise exceeds 12 ft; stringers bear on footings below frost depth, not on pads or patios that aren’t founded that deep.