Build safe, code-compliant stairs. Calculate riser height, tread width, and total stringer length based on your total rise.
Standard building codes typically require a maximum rise of 7.75". Your calculated rise is .
The key to building stairs is dividing the total height (Total Rise) by a standard step height (approx. 7 to 7.75 inches).
Measure from the top of the finished floor below to the top of the finished floor above.
Step 2: Determine StepsDivide Total Rise by 7 or 7.5. Round this number to the nearest whole number to get your number of steps.
Step 3: Calculate Exact RiserDivide Total Rise by the number of steps. This is your exact rise per step.
International Residential Code (IRC) measurements are standard, but always check your local codes.
Ideally, stairs should be between 30° and 37°. A standard 7-inch rise with an 11-inch run gives a comfortable 32.5° angle.
The stringer is the structural board (usually 2x12) that supports the treads and risers on either side of the staircase.
