How to Measure for Stair Runner: Step-by-Step Guide

Ordering a stair runner that comes up 18 inches short is a painful mistake, because runners are usually cut from a single roll and a second piece rarely matches. Learning how to measure for stair runner length and width correctly takes about 20 minutes with a tape measure and a notepad, and it saves you from wasted material or an awkward seam on the most visible step. The process is simple once you know which dimensions matter, how installation style changes the math, and where to add allowance.

Part of our Stairs & Stair Flooring guide — explore the full guide →

How to Measure for Stair Runner: Tools and Terms

Gather a 25-foot tape measure, a flexible sewing tape or cloth measure for nosings, a pencil, and a simple sketch of your staircase. Before you measure, get familiar with a few terms:

• Tread: the horizontal surface you step on, usually 10 to 11-1/4 inches deep.
• Riser: the vertical face between treads, typically 7 to 7-3/4 inches tall.
• Nosing: the rounded front edge of the tread that projects past the riser, usually 3/4 to 1-1/4 inches.
• Exposed border (reveal): the strip of bare stair visible on each side of the runner.

Also decide on installation style first, because it changes the length calculation. A waterfall install drapes the runner straight down from the nosing to the next tread, leaving a gap behind it. A Hollywood (or upholstered) install wraps the runner tightly under each nosing and down the riser, using a bit more material.

Step 1: Measure One Tread and One Riser

Most staircases are built with consistent tread and riser sizes, so you can measure one typical step and multiply. Still, check at least three steps top, middle, and bottom, because older homes often vary by 1/4 inch or more.

1. Measure tread depth: from the back of the tread where it meets the riser to the front edge of the nosing.
2. Measure riser height: from the top of the lower tread up to the underside of the nosing above.
3. Measure the nosing wrap (Hollywood only): run a flexible tape around the curve of the nosing from top to underside. This typically adds 1 to 2 inches per step.

Example: a tread of 10-1/2 inches plus a riser of 7-1/2 inches equals 18 inches per step for a waterfall install. For a Hollywood install, add the nosing wrap, perhaps 1-1/2 inches, for 19-1/2 inches per step.

Step 2: Count the Steps and Calculate Total Length

Count the number of treads that will be covered. A standard floor-to-floor staircase usually has 12 to 14 risers. Decide whether the runner starts at the bottom riser (common) and whether it ends at the top riser or continues onto the upper floor as a short tongue.

Use this formula:

• Total length = (tread + riser + nosing wrap) x number of steps + allowance

With 13 steps at 18 inches each, the waterfall length is 234 inches, or 19 feet 6 inches. Add 6 to 12 inches for trimming, pattern matching, and the finished ends. Round up and order 20 feet 6 inches or 21 feet. For patterned runners with a large repeat, add one full repeat length, which may be 12 to 36 inches, so you can center the pattern on the top and bottom steps.

Step 3: Choose and Measure the Runner Width

Width is a design decision more than a measurement, but it starts with your stair width. Measure each tread from wall or stringer to stringer. Standard residential stairs are 36 inches wide, and wider feature staircases run 42 to 48 inches.

A good rule is to leave 3 to 5 inches of exposed wood on each side. That means:

• 36-inch stairs: 27-inch runner (4-1/2-inch reveal each side).
• 40-inch stairs: 30 to 32-inch runner.
• 42 to 48-inch stairs: 32 to 36-inch runner.

Stock runners commonly come in 26, 27, 30, and 32-inch widths. Custom widths are possible when broadloom carpet is cut and bound, at an added binding cost of $3 to $8 per linear foot. Keep the reveal consistent on both sides; an off-center runner is very noticeable from the bottom of the stairs.

Measuring Landings, Turns, and Winders

Straight stairs are easy, but many homes have a landing or a turn. Treat each section separately and add the pieces together.

Flat Landings

Measure the landing along the path the runner will travel, both length and width. A runner can continue across the landing as one piece, or the landing can get a separate rug-style piece. For an L-shaped stair with a square landing, the runner is usually mitered at a 45-degree angle at the turn, which requires about one runner width of extra material, such as an additional 27 to 32 inches.

Winder Steps

Pie-shaped winder treads are the hardest to measure. Measure each winder at its widest point along the walking line, about 12 inches from the narrow end, and at the full outside depth. Runners on winders are typically cut and fitted step by step, so add 15 to 20 percent extra and plan on professional installation.

Bullnose Bottom Steps

A rounded bottom step that flares wider than the rest needs its own piece. Measure the full curve and depth, and ask your installer whether they plan to wrap the runner around the curve or stop it square at the edge.

Worked Example for a Typical Staircase

Consider a straight 36-inch stair with 13 steps, 10-1/2-inch treads, 7-1/2-inch risers, a 1-1/4-inch nosing wrap, and a Hollywood install.

1. Per step: 10.5 + 7.5 + 1.25 = 19.25 inches.
2. 13 steps x 19.25 = 250.25 inches.
3. Add 12 inches allowance: 262.25 inches.
4. Convert: 262.25 / 12 = 21.85 feet. Order 22 feet of 27-inch runner.

At $30 to $70 per linear foot for a quality wool or nylon runner, material costs for this stair land between $660 and $1,540. Professional installation typically adds $15 to $30 per step, plus $50 to $100 for rods or special cuts.

Padding, Rods, and Other Material

Stair runners need padding for comfort and to extend their life. Pads are cut about 1 to 2 inches narrower than the runner and only cover the tread and wrap over the nosing, not the full riser. For 13 steps, you will need 13 pieces sized about 25 inches wide by 13 to 15 inches deep. A dense 1/4-inch felt or rubber-felt pad is ideal; thicker pads make steps feel spongy and can reduce tread depth, which is a tripping risk.

Decorative stair rods are measured to extend 1 to 2 inches past each side of the runner. For a 27-inch runner, 30 to 31-inch rods work well. You need one rod per riser, so 13 rods for our example. Rods are decorative and should never be the only thing holding a runner in place; staples or tack strip do the real work.

Choosing Runner Material Before You Order

Your measurements tell you how much to buy, but the material affects how forgiving the fit will be. Wool runners are dense and slightly stretchy, which makes them easier to tuck tightly around nosings in a Hollywood install. Flatweave and sisal runners have little give, so accurate tread and riser measurements matter even more; a sisal runner that is 1/2 inch off per step will show a crooked line by the top of the stairs. Nylon and polypropylene loop-pile runners are durable and budget friendly at $15 to $35 per linear foot, but thicker cut-pile styles need an extra 1/4 to 1/2 inch per step to wrap the nosing. When in doubt, request a sample and wrap it around one of your actual nosings to confirm the allowance.

Common Measuring Mistakes to Avoid

• Measuring only one step: older or site-built stairs often vary, so measure several.
• Ignoring installation style: a Hollywood wrap can add 15 to 25 inches of length over a full staircase.
• Forgetting pattern repeats: patterned runners need extra length to center the design.
• Skipping allowance: always order at least 6 inches extra, and more for landings or turns.
• Not checking the top step: decide early whether the runner ends at the top riser or flows onto the floor above.
• Choosing too wide a runner: less than 3 inches of reveal can look cramped and makes attaching to stringers difficult.

Write every measurement on your sketch, including the stair width at the top, middle, and bottom, and take phone photos of any tricky sections. Bring that sheet to the store or send it to your installer. Knowing how to measure for stair runner length and width accurately means you order once, pay once, and end up with a runner that fits cleanly from the first step to the last.