Geometry for a stair stringer layout
The rise per step and going are the repeated dimensions of the stair. The diagonal shown is a geometric reference between floors; it does not include board ends, support cuts or stock allowance. The elevation is not a cutting template. Tread thickness and bottom-riser adjustment depend on the finished floor and connection details.
Save the measurements with the sketch
Use the measurement brief to record floor finishes, opening measurements and unresolved site details. PDF and print include the selected elevation, exact riser calculation, nosing projection and all entered assumptions.
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Stair planning
Frequently asked questions
Can this size a structural stringer?
No. Structural sizing, spacing, connections and remaining wood below cuts require a separate design.
Why keep the exact riser height?
Repeatedly rounding a riser can accumulate error across the flight. Keep the full calculation and confirm the finished layout before marking or cutting.