Measurement Guide – How to Measure Windows for Curtains
Measuring a window for curtains takes about five minutes and a metal tape measure — but getting it wrong is the most common (and most expensive) mistake people make when ordering made to measure curtains. This guide walks you through exactly how we measure windows for our own customers across Ireland: width, drop, fullness, and the awkward cases like bay windows and radiators. Follow it step by step and your curtains will fit first time.
Before You Start: What You Need
- A metal tape measure — fabric tapes stretch and give false readings
- A pencil and paper (or your phone) to note each measurement
- Your pole or track already fitted — this matters, see below
- A second pair of hands for wide windows (optional, but easier)
Always measure in centimetres, and measure twice. We list inch equivalents below because many ready-made curtains are still sold in inches, but for made to measure orders we work in centimetres.
Step 1: Fit the Pole or Track First
You measure curtains from the pole or track, not from the window itself. If yours isn’t up yet, fit it first (or decide exactly where it will go). As a rule of thumb:
- Position the pole or track 10–15cm above the window frame — higher makes the window look taller
- Extend it 15–20cm beyond the frame on each side, so open curtains stack back off the glass and let in maximum light
- Wave curtains need a wave-compatible track (not a pole) — worth deciding before you measure
Step 2: Measure the Width
Measure the full length of the pole between the finials (the decorative ends), or the full length of the track. Do not measure the window — the pole is what the curtains hang from, so the pole sets the width.
This is the width you give us. We add the fullness for the heading style you choose — you don’t need to double anything yourself. If you’re curious how much fabric different headings use, see the fullness table further down.
Step 3: Measure the Drop
The drop is the finished length of the curtain, top to bottom. Where you measure from depends on your heading, and where you measure to is a style choice.
Measure from:
- Pole with rings (French pleat, goblet, gathered, box pleat): measure from the bottom of the curtain rings
- Track (including wave): measure from the top of the track
- Eyelet curtains: measure from the top of the pole, then we allow for the fabric that sits above the eyelets
Measure to:
- Sill length: 1cm above the sill — practical for kitchens and windows with radiators below
- Below the sill: 15cm below the sill — a neat, traditional finish
- Floor length: 1cm above the floor — the most popular choice for living rooms and bedrooms, clean and full-height
- Puddled: add 5–10cm to floor length for a soft, luxurious break — best with heavier fabrics
Standard Curtain Sizes in Ireland
Ready-made curtains in Irish shops come in a small set of standard sizes. If your measurements fall between them — as most windows do — that’s exactly what made to measure solves.
| Measurement | Centimetres | Inches |
|---|---|---|
| Standard widths (per curtain) | 117cm / 168cm / 228cm | 46″ / 66″ / 90″ |
| Standard drops | 137cm / 183cm / 229cm | 54″ / 72″ / 90″ |
| Extra-long drops | 274cm | 108″ |
How Much Fabric? Fullness by Heading Style
Fullness is how much wider the flat fabric is than the pole, which is what gives curtains their folds. We calculate this for you on every made to measure order, but it’s useful when comparing quotes or buying curtain fabric by the metre.
| Heading style | Typical fullness |
|---|---|
| Gathered / pencil pleat | 2 – 2.5× pole width |
| French (pinch) pleat | 2 – 2.5× pole width |
| Goblet pleat | 2 – 2.5× pole width |
| Wave | 2× track width |
| Box pleat | 2.5 – 3× pole width |
| Eyelet | 1.75 – 2× pole width |
The Awkward Cases
Bay windows
Measure along the track itself, following the curve or angles of the bay — never straight across the opening. For a three-section bay, note each section separately. Bays almost always need a track rather than a pole, and they’re the window we most recommend letting us measure in person.
Radiators under the window
Full-length curtains that cover a radiator will trap its heat behind the fabric. Either go sill-length (finishing 2–3cm above the radiator), or pair floor-length dress curtains with a blind that does the practical work.
Uneven floors and sills
Older Irish homes rarely have level floors. Measure the drop at both ends and the middle of the pole, and give us the smallest figure — a curtain that just clears the floor everywhere looks far better than one that drags at one end.
Common Questions
Do I measure the window or the pole?
The pole, always. The window’s size only matters for deciding where the pole goes.
Should the measurement include both curtains?
Give us the full pole width once — we split it across the pair and add fullness. Don’t halve or double anything.
What if I’m between standard sizes?
Most windows are. That’s the case for made to measure curtains — cut to your exact width and drop, in the fabric you choose.
What if I get it wrong?
Send us your measurements before ordering and we’ll sense-check them against your window type and heading style. Or skip the tape measure entirely — see below.
Have Your Measurements? Get Your Quote
Send us your width, drop, and the room it’s for, and we’ll come back to you with a made to measure quote — or call us on (045) 433 585, or visit the Portlaoise showroom to see the fabrics in person. Not confident in your numbers? Say so in the message and we’ll talk you through it.