Deck Stairs — 36 Inch Total Rise
A deck that is 36 inches off the ground needs 5 risers at 7.2 inches each with standard 10-inch treads.
How to use this tool
- Measure the total rise from the lower finished floor to the upper finished floor.
- Enter a comfortable target riser height (about 7-7.75 in).
- Enter the tread depth (run per step), at least 10 in for most codes.
- Read the riser count and the exact riser height to cut.
- Confirm the total run fits your available floor space.
Calculate the number of risers and stringer length for deck stairs dropping about 3 feet to grade.
Frequently asked questions
- How many stairs do I need for a given height?
- Divide the total floor-to-floor rise by a comfortable riser height (about 7.5 in) and round to the nearest whole number. A standard 108-inch rise gives 14 risers and 13 treads.
- What is a comfortable riser height?
- Around 7 to 7.75 inches. Most codes cap risers at about 7.75 inches, and a common comfort rule is that two risers plus one tread should total 24-25 inches.
- Why is there one fewer tread than riser?
- The upper floor acts as the final landing, so the top riser steps onto the floor instead of onto a tread. A flight therefore always has one more riser than tread.