Stair Runner Length Chart by Step Count

What a length chart is actually showing

A stair runner length chart maps step count directly to an estimated total length, using an assumed set of tread run, riser height, nosing wrap and finishing allowance figures held constant across every row. That's useful for a fast estimate, but it's important to understand what's baked into the numbers, because two charts built on slightly different assumed tread and riser dimensions can disagree by a foot or more on the same step count. The chart in this guide assumes a standard residential tread run of 10 in (25 cm), riser height of 7.5 in (19 cm), a 0.75 in (1.9 cm) nosing wrap, a 24 in (61 cm) combined top-and-bottom finishing allowance, and a 7% waste margin.

Length chart by step count

Below is the full chart across the step counts most residential staircases fall into, from a short 9-step half flight up to an 18-step full-height flight. Use it to sanity-check your own measured figure, or as a first estimate before you measure, but remember any deviation in your actual tread run or riser height from the assumed standard figures shifts every row proportionally.

How much runner do I need?

To see exactly how the chart figures are derived, walk through the 13-step row in full. Per step: 10 in tread run + 7.5 in riser height + 0.75 in nosing wrap = 18.25 in. Across 13 steps: 237.25 in. Add the 24 in finishing allowance: 261.25 in, which is 21.77 ft. Apply the 7% waste margin: 261.25 x 1.07 = 279.5 in, or 23.29 ft, rounding to the chart's listed 23.3 ft. In metric terms: 25 cm + 19 cm + 1.9 cm = 45.9 cm per step, x13 steps = 596.7 cm, plus 61 cm finishing allowance = 657.7 cm, x1.07 waste margin = 703.7 cm, or roughly 7.04-7.1 m depending on rounding, matching the chart's 7.1 m figure.

If your own staircase has a different riser height, adjust the chart estimate proportionally rather than reading it as fixed. A staircase with an 8 in (20 cm) riser instead of 7.5 in (19 cm) adds roughly 0.5 in (1.3 cm) per step, which across 13 steps adds about 6.5 in (16.5 cm), plus its own 7% waste share, to the chart's listed figure - not enough to derail a budget estimate, but enough that you shouldn't order to the exact foot or metre without checking your own numbers via a stair runner calculator first.

Adjustment guide for non-standard risers

• Riser 7 in (18 cm): subtract roughly 0.5 in (1.3 cm) per step from the chart figure.
• Riser 7.5 in (19 cm): use the chart figure as-is.
• Riser 8 in (20 cm): add roughly 0.6 in (1.5 cm) per step to the chart figure.
• Tread run 11 in (28 cm) instead of 10 in (25 cm): add roughly 1 in (2.5 cm) per step.

Using the chart to compare fitter quotes

One of the most practical uses of a length chart isn't estimating your own order, it's sanity-checking a quote you've already been given. If a fitter or supplier quotes a length for your step count that's dramatically higher or lower than the chart row for that count, ask what's included - some quotes bundle in extra material for a pattern repeat or turn that the plain chart figure doesn't account for, while others might be quoting bare tread-plus-riser length with no nosing wrap or waste margin at all, which will run short once fitted. A stair runner length calculator lets you plug in the fitter's assumed tread and riser dimensions directly, if they've shared them, so you can compare like-for-like rather than guessing.

Landings and turns aren't on this chart

This chart, like most published length charts, covers straight flights only. Any staircase with a half landing, full landing, or winder section needs the landing or winder measured and added separately, following the actual walked line across those treads rather than a straight tape measurement, plus a higher waste margin of around 10% rather than 7% to cover the extra trimming those sections require. Treat the chart figure for your straight-run step count as a starting subtotal, then add your landing or winder allowance on top.

When the chart is close enough to order from

For a straightforward straight flight with standard, code-typical tread and riser dimensions and a plain or non-repeating pattern, the chart figure is usually within an inch or two of a properly measured figure, close enough for most practical ordering purposes with a small safety margin already built in via the waste percentage. Where it isn't close enough is anything non-standard: steep older staircases, winders, patterned runners with a fixed repeat, or particularly deep bullnose nosings. In those cases, measure directly and run the numbers through a calculator rather than trusting the chart's flat assumptions.

Still deciding on material, width or pattern? Our hub on stair runners compares weaves, widths, backings and fitting styles side by side, then hands the numbers straight to the calculator.