Stair Paving Calculator

How the calculation works

Stones = ceil(steps × width(ft) × 12 × tread(in) / stone area(in²) × (1 + allowance / 100)).

Worked example

With number of steps 5 steps, stair width 4 ft, tread depth 12 in, stone length 12 in, stone width 12 in, extra allowance 10 %, stair paving is 22 stones.

Assumptions and limits

Treads only; uniform steps and stones. No risers, cutting plan or structural design.