how to measure stair carpets

How to Measure Stair Carpets in 2022 (Step-by-Step DIY Guide & Pro Tips) – UK Edition

Homeowners often think it’s too difficult to do anything with their stairs. They’re not confident enough to replace their stair carpet themselves. However, hiring a professional carpet fitter is expensive, as we recently explained in our guide to carpet fitting costs.

Moreover, stair carpet fitting isn’t as tough as you may think. It starts with taking accurate measurements, which is what this simple step-by-step (sorry, pun intended) guide on how to measure stair carpets will cover.


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Tools List

  • Tape measure
  • Pencil and paper
  • Calculator (if you don’t trust your mental maths)

How to Measure Stair Carpets – Step-by-Step Instructions

As with many jobs, preparation is key to fitting stair carpets. That starts with making an accurate measurement of how much carpet you need.

When you fit the carpet and find you don’t have enough, there’s very little you can do. That’s why our method relies on the idea of measuring twice and cutting once.

1. Preparing the Stairs

preparing stairs for carpet

You need accurate measurements of the floor area you’re covering with your new carpet. To get that, you must measure the bare stairs themselves.

So before you get to measuring, remove any existing carpet and strip things back.

2. Measuring a Tread

measuring a tread for carpet

The first step to determining exactly how much carpet you need for your stairs involves measuring each tread. The tread is the flat horizontal part of each step you stand on when using the stairs. Using a tape measure, take an accurate measurement of the width and depth of the tread.

If the tread on your stairs overhangs the riser (the vertical part), you need to account for this. Measure around the overhanging edge of the tread and add it to the depth measurement.

Write down the exact measurements. Next, round up each figure to the nearest centimetre and write down these measurements.

Note: For each measuring step in this process, note the exact and rounded-up measurements. So two sets of measurements for each measurement. The exact measurements are used for the fitting stage, and the rounded-up measurements are used when buying the carpet. Make sense? Good, let’s continue…

Pro Tip: You don’t need to measure the tread’s full width if you use a runner rather than a full stair carpet. In that case, only measure the width of the tread the runner will cover.

A stair runner is an attractive interior design choice, as Carpetright explains. If you use one, some of the wood will remain visible. Homebuilding’s handy guide to reviving wood floors will help ensure it’s looking its best.

3. Measuring a Riser

measuring a riser for carpet

Your next step is to measure a riser on your staircase. The riser is the vertical part of each step. You need to measure the height and width of the riser.

The width ought to be the same as that of the tread, but it never hurts to double-check. Note down your exact measurements and then round each one up. Make a note of the rounded figures too.

4. Measuring Landings

measuring landings for carpet

If your staircase has a small landing part-way up, your carpet will need to cover this too. Take accurate measurements of the width and depth of the landing. Note these figures and include the same rounded-up measurements as before. Multiply the width of the landing by the depth to find its total area. Do this with both the exact and rounded figures.

Pro Tip: Don’t forget that a landing will have a riser beneath it, just like any other step on your stairs. Make sure to include the height of that riser in your measurement of the landing’s depth.

5. Calculating Area

You now have all the measurements you need to calculate the total area your stair carpet needs to cover. First, you need to add your measurement for the depth of a tread to that of the height of a riser. Then, multiply that figure by the width of the tread and riser (which should be the same). You’ve now got the total area of one step. Multiply this by the number of steps on your stairs. Add that figure to the total area of any landing and write down the resulting figure. Repeat this process with your rounded-up measurements.

6. Repeat Steps 2 to 5

You’ll now want to work through steps two to five for a second time. Once you have, check your recorded measurements (exact and rounded) against your first set. You want each and every measurement to match. This is the only foolproof way to discover if you made a mistake anywhere along the way.

If all your figures match, you’re ready to move on. If they don’t, you’ll have to measure everything again until they match.

7. Get Cutting and Fitting

fitting stair carpets

Once you’re sure of your measurements, you can start cutting your carpet. It’s best to use your rounded-up figures and then add around another 2.5cm for each step.

If you use underlay, you must add approximately 50cm to the total area. That way, you’ll have a little slack to account for any mistakes whilst carpet fitting.

You’re now ready for the next step – carpet fitting! This job will be much easier now you’ve got the right amount of carpet.


Don’t fancy doing this job yourself? Find top-rated carpet fitters in your area by clicking the button below:


How to Measure Stair Carpets – Final Thoughts

Our simple guide on measuring stair carpet might not have put you on a stairway to heaven, but it should have made you more confident about livening up your stairs without having to call in a professional.

For more carpet/stairs decor tips, check out our guide to fitting half carpet and half laminate on your stairs.