MCPCalc

Stair Calculator

Design stairs with code-compliant riser height, tread depth, and total run.

Scratchpad (not saved)

in

Floor-to-floor height

in
in

What This Calculator Does

Design stairs with code-compliant riser height, tread depth, and total run.

It combines Total Rise, Desired Riser Height, Stair Width to estimate Number of Risers, Actual Riser Height, Number of Treads.

Formula & Method

Risers are N_r=\text{round}\left(\frac{Rise_{total}}{R_{desired}}\right) and actual riser height R=\frac{Rise_{total}}{N_r}. Treads N_t=N_r-1 and tread depth follows T=25-2R. Total run Run=N_t\cdot T and stringer length S=\sqrt{Rise_{total}^2+Run^2}.

Notation used in the formulas: R = Number of Risers; x_{1} = Total Rise; x_{2} = Desired Riser Height; x_{3} = Stair Width.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

  • Total Rise: Floor-to-floor height
  • Desired Riser Height: Used directly in the calculation.
  • Stair Width: Used directly in the calculation.

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