ClarityHow to use this tool
- Enter number of steps, stair width, tread depth, riser height, waste allowance.
- Select Calculate to view the result.
- Check the method and assumptions below before using the result.
The method, explained
Area = step count × width × (tread depth+riser height), with allowance.
Using number of steps = 12, stair width = 0.9 m, tread depth = 0.28 m, riser height = 0.18 m, waste allowance = 10 %, the result is 5.4648 m². Change these example inputs to match your task; use the method above to check each step.
Understanding your result
Excludes landings, winding stairs and extra nosing wrap. Roll width and pattern alignment can increase purchased material.
What to keep in mind
Excludes landings, winding stairs and extra nosing wrap. Roll width and pattern alignment can increase purchased material. A material-quantity estimate, not a structural design or building-code check. Confirm site measurements, supplier coverage and waste before ordering.
Common questions
How do I use this stair carpet calculator?
Estimate carpet surface area covering rectangular stair treads and risers. Enter number of steps, stair width in m, tread depth in m, riser height in m, waste allowance in %. The starting example is editable; use values for the same system or project.
Which assumptions affect this result?
Excludes landings, winding stairs and extra nosing wrap. Roll width and pattern alignment can increase purchased material.
Methodology maintained by ClarityKit. How these tools are built and checked.