Stair Rise Calc
Answer Worked out from a total rise of 96.00 inches, floor to floor.

Rise and run calculator

Rise and run 67/8in×11in
Total rise
96in96.00 in8 ft
2 risers + 1 tread
2411/16in
One step as the unit the flight repeats: 6.857 inches of rise against 11.00 inches of run. Below it the same pair laid end to end as two risers and one tread, 24.71 inches together. Riser height67⁄8 in Tread run11 in 2R + T2411⁄16 in
Given

What this was worked out from

in
in
in
in
in

These are the figures every number on this page is worked for.

Solution

Every dimension of this flight

To the nearest sixteenth
DimensionValue
Total rise 96in96.00 in8 ft
Risers 14
Riser height 67/8in6.857 in
Treads 13
Tread run 11in11.000 in
Total run 143in143.000 in11 ft 11 in
One step along the edge 1215/16in12.962 in
Marked length 1811/2in181.472 in15 ft 1.47 in
Stringer length 1721/4in172.235 in14 ft 4.24 in
Board length 16ft
Angle 31.9°
Stringer angle 33.9°
2 risers + 1 tread 2411/16in24.71 in2 ft 0.71 in
Bottom cut deduction 1in1.000 in
Tread thickness 1in1.00 in
Nosing 1in1.00 in
Stair width 36in36.00 in3 ft
Options

The pairs that work at this height

Riser Tread 2R + T Angle Result
61/2in 11in 24in 30.6° Within
61/2in 111/2in 241/2in 29.5° Within
61/2in 12in 25in 28.4° Within
63/4in 101/2in 24in 32.7° Within
63/4in 11in 241/2in 31.5° Within
63/4in 111/2in 25in 30.4° Within
7in 10in 24in 35.0° Within
7in 101/2in 241/2in 33.7° Within
7in 11in 25in 32.5° Within
71/4in 10in 241/2in 35.9° Within
71/4in 101/2in 25in 34.6° Within
71/2in 10in 25in 36.9° Within

One riser and one tread together measure 17.86 in.

Code

Each figure against the limit it has to meet

Dimension Limit Code Result
Riser height, maximum 73/4in IRC 2021 (residential) Within
Tread depth, minimum 10in IRC 2021 (residential) Within
Stair width, minimum 36in IRC 2021 (residential) Within
Riser height, minimum 4in ADA 2010504.2 Within
Riser height, maximum 7in ADA 2010504.2 Within
Tread depth, minimum 11in ADA 2010504.2 Within
Nosing projection, maximum 11/2in ADA 2010504.5 Within
Calculators

Work out one part on its own

Source

Where the limits come from

2 sources, with the date each was read

Building codes are adopted and amended locally. Confirm every figure with the code your jurisdiction has adopted before you cut.

Updated September 2026