Measuring guide
How to measure for curtains
Two figures, both in millimetres: the width of the track or pole and the drop from it to where the curtain should finish. This guide shows where each comes from, and the extras that matter on a contract job.
Before you start
Use a metal tape, not a fabric one. Write every figure in millimetres with the unit beside it. Measure each window separately even if they look the same; on site they rarely are.
Measuring the width
Curtains hang from the fixing, so the width we need is the length of the track or pole, not the window.
If you have an existing track
Measure the track from end to end and give us that figure. If the track has an overlap arm at the centre or returns to the wall at the ends, tell us and we allow for them (see below).
If you have an existing pole
Measure between the decorative ends (finials). Don't include the finials; the curtain never travels past the bracket. For eyelet curtains also tell us the pole diameter so the eyelets are sized to run freely.
No track or pole yet?
Measure the width of the window recess and add 300mm (150mm each side). That gives the track or pole room to sit either side of the window so the curtains clear the glass when open. Use this figure as the width and order the track to match.
Stack-back on wide or heavy windows
When curtains are open they stack at each end of the track. On a wide window, or with a full heading such as pinch pleat, 150mm a side is not always enough to keep the stack off the glass. As a rule of thumb allow about 15% of the window width each side for a pair, and tell us if you need the glass fully clear; we can size the track for the heading you choose.
Measuring the drop
The drop is measured from the fixing down, not from the top of the window.
Where should curtains finish?
Curtains look best finishing in one of three places:
- A — 10mm above the floor
- B — 10mm above the sill
- C — 150mm below the sill, or 20mm above a radiator
Measure from the top of the track to the point you want the curtain to finish.
Measuring from a pole
Measure from the eye of the curtain ring, which is where the curtain actually hangs. For eyelet curtains measure from the top of the pole, because the fabric sits above it.
Measure in two or three places
Floors and sills are rarely level. Measure the drop at each end and in the middle and give us the smallest figure. A curtain that is 10mm short of the floor looks right; one that is 10mm too long puddles and wears.
No track or pole yet?
Measure from 100mm above the recess down to where you'd like the curtain to finish. Fix the track or pole at that height when it arrives.
Contract details worth noting
None of these change the two figures above. They change how we make the curtain up, so note them on your schedule when they apply.
Returns
A return is the short length of curtain that wraps back from the end of the track to the wall, closing the gap light would otherwise leak through. It is standard on blackout and dimout curtains. Tell us the track's projection from the wall (bracket depth) and we add the returns; you don't need to add anything to the width.
Centre overlap on a pair
Tracks with an overlap arm let the two leading edges cross by about 100mm so there is no gap at the centre. Tell us if the track has one; we make each curtain slightly wider to suit. Poles don't overlap, so a pair on a pole meets edge to edge.
Ceiling-fixed tracks
Measure the drop from the ceiling to the finish point and tell us the track type. Gliders on a ceiling-fixed track sit a little below the ceiling, and the allowance differs between tracks, so we make the deduction rather than you.
Bay windows
Measure each straight run of the track (or of the recess, if there is no track yet) and note the angle at each corner or send a photo. A bay usually takes one curtain each end and sometimes one per face; we advise on the split once we have the runs.
Double tracks: curtain and voile
Measure the width and drop of each track separately; the rear track for the voile is usually shorter. The voile is normally made 20mm shorter than the curtain so it never shows below the hem.
What to write down
Per window, so we can quote and make without coming back to you:
- Room / window reference
- Your own reference, e.g. Room 204 W1. It goes on the label sewn into the curtain.
- Fixing
- Track, pole or none yet. Overlap arm yes/no. Returns yes/no and bracket projection in mm.
- Width
- Track end to end, or pole between finials, in mm.
- Drop
- From the top of the track (or ring eye / top of pole) to the finish point, in mm. Smallest of three.
- Finish point
- A floor, B sill or C below sill / above radiator.
- Heading and lining
- Pencil pleat, pinch pleat, wave or eyelet; standard, dimout, blackout or interlined.
- Single or pair
- Pair unless the track is a single draw.
Rather we measured?
For larger projects we can measure on site. Site surveys carry a fee that depends on the location, the number of windows and the stage of the build; we confirm it before anything is booked. Site surveys and installation.
Frequently asked questions
Do I add anything for hems or headings?
No. Give us the finished width and drop and we add the fullness, turnings and hems. The only figures we need are the ones in this guide.
The floor slopes. Which drop do I give you?
The smallest. A pair made to the shortest drop will sit 10mm above the floor at the low point and a few millimetres higher at the other end, which is not noticeable. Made to the longest drop it would drag.
How accurate does the measurement need to be?
To the nearest 5mm is plenty. What matters more is that the width is the track or pole, not the window, and that every figure is in millimetres.
Can you measure for me?
Yes. For larger projects we can measure on site. Site surveys carry a fee that depends on the location, the number of windows and the stage of the build; we confirm it before anything is booked.
Ready to price?
Enter your width and drop on any curtain product page for an instant price, or add several fabrics to a project quote and send us the schedule.