NotchlineStairs and rafters, worked out
The stair that fits the hole you have
Give Notchline the floor-to-floor height and the opening. It finds the stairs that fit, checks each one against your stair code rule by rule, and solves the rafter from whatever you can measure.
- Pay once
- No account
- Works offline
- 9 languages
- Riser
- 6 ¹³⁄₁₆″
- Going
- 11 ⁷⁄₁₆″
- Angle
- 30.8°
- Code check
- ✓ 4 of 4 rules within limits
What it does that others don't
Fit the hole
Height, opening, floor depth and the room you have. It tries straight, landing, L, U, winder and spiral stairs and keeps the ones that fit and stay within every rule, headroom included. If nothing fits, it says what would.
The inspector sheet
Every rule of your code on one page: clause, limit, your number, a plain verdict and the smallest fix. Print it as a PDF, in your language or the code's, and check the same stair against a second code.
The roof from what you can measure
Any two of run, rise, pitch and rafter length give the rest. The birdsmouth is checked against a quarter of the rafter depth. No pitch on the plans? The phone measures it.
Stringer layout
Framing square settings, the drop at the first riser, the throat left in the board and the board to buy. Pro draws the stringer with every mark.
Job card
One picture with the drawing, the numbers and the verdict, to send to the client, a coworker or the lumber yard.
A keypad for site numbers
A feet key, one-tap fractions to 1/16 or 1/32, tape-measure display, or mm and cm with your decimal mark.
Free calculators on this site
The straight-stair and common-rafter core of the app, in your browser, with the same formulas and rule numbers.
- Stair calculatorFloor-to-floor height in; risers, treads, run, stringer and every rule of your code out.
- Rafter calculatorAny two of span, rise, pitch and rafter length; the rest, the overhang and the birdsmouth check.
- How the numbers are checkedPublished worked examples next to what this site's calculator gives.
Free in the app, for good
- Straight stairs with every number and the headroom
- Your country's code check, rule by rule
- What would make it fit, when nothing does
- Common rafter, overhang and the birdsmouth check
- Pitch gauge, stringer numbers, job card
- Unlimited jobs and one-file backup
Pro, one payment
- Landings, L and U stairs, winders and spirals in the search
- The same stair against a second code
- The inspector sheet as a PDF
- The stringer drawn with every mark
- Hips, valleys and jacks, unequal pitches too
Try Pro free for 7 days. Nothing renews and no card is asked. When Pro ends, every job stays readable, editable and exportable.
Nothing leaves your phone
No account, no analytics, no ads, no tracking. Jobs stay on the phone. The only network use is a purchase through the store.
Numbers you can check
Every result shows its formula with your numbers. The engine runs 353 test cases, 91 of them against published worked examples, and this site's calculators are checked against it.