Figure

Roof and stairs

Roof sheathing

Find horizontal sheathing run from roof pitch and sheet width along the slope.1

A sheet measured along the roof slope covers a shorter horizontal distance. Use the roof pitch to relate that sloping sheet width to its horizontal projection; neither is the full roof span.

Find the sheathing run

Use roof pitch and sheet width along the slope.

Start a new calculation

Use 2nd if a unit is above its button.

  1. Start fresh

    Press Clear entry, then Clear entry.

  2. Press the keys

    Press Select length units.

Open Right

Skip if Right is already open. Skip Close if no mode is open.

  1. Press Close calculation mode, then Open Right Triangle.

Enter and calculate

  1. Inches of rise per foot

    Press 6, then inches, then Store pitch.

  2. Sheet width

    Press 4, then feet, then Store diagonal.

  3. Complete the value

    Press Equals.
  1. Example result3 feet 6 and 15/16 inches

Keep in mind

Rounded measurements retain their underlying value unless the workflow explicitly rounds a stair step.

Display assumptions

  1. Fraction precision: 1/16″; Fraction format: Simplified; Angle decimal places: Variable. ↩

Keep the guide beside your calculation.

These examples are built into Figure. Open Help while you calculate, then return to the same guide and reading position.

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