How to Measure Curtains
If you want to measure for curtains, this involves taking two measurements on your window – the width and the drop. You will get the most accurate measurements if your pole or track is already fitted and you measure with it in place.
- In order to measure for curtains correctly, you will need to know what kind of curtains you want and how long you want them to be. For eyelet curtains you should measure the drop from 1”/2.5 cm above the pole to where you want the curtain to finish. For tab top curtains measure from the top of the pole and then subtract the length of the tabs you are making. For other finishes on poles you should measure from the bottom of your curtain rings to where you want the curtain to finish. For curtain track you should measure from the top of the track to where you want the curtain to finish.
- Curtains within a window recess usually finish just above the windowsill. Curtains hung outside a window recess usually finish below the windowsill (approx 4-6”/10-15cm or to your preference), but you can choose to make them longer if you desire. Floor length curtains can finish just above the floor (to make them easy to draw), just on the floor (to keep out draughts), or can be made a couple of inches longer to add weight.
- Once you have measured the drop then you need to measure the width of your track or pole. Add in any overlap which is in place on your track fixings. For poles measure from just outside where the pole is fixed to the wall on each side.
Calculate Curtain Fabric
The next step is to calculate how many widths of fabric you will need for your window. This will depend on how full you want your curtains.
- For standard pencil pleat heading we recommend double fullness (multiply the width by 2).
- For triple pleat curtains you may need 2.5 times fullness (or as recommended on any tape you are using) (multiply the width by 2.5)
- For eyelet curtains you need between 1.5 times fullness (adequate) and 2.25 times fullness (maximum). You will need to make sure you have an even number of eyelets on your finished curtains. Our eyelet curtain header tape has 8 eyelets per metre of tape.
When you have multiplied your measured width by the fullness you need, divide this figure by the width of the fabric:
eg. Measured width 210cm
x 2 for fullness = 420cm
divided by fabric width (137cm) = 3.07
You will then need to round this figure to the exact number it is closest to. In this example the figure is just over 3 so you would use 3 widths of fabric (one and a half in each curtain for a pair of curtains). If the figure was just below (eg 2.85) you would go up to 3. If in doubt go up to the next number of widths as curtains with more fullness look better.
Now you know how many widths you need the next stage is to calculate the length of fabric you need for each width. You will need to add a hem allowance to your drop. We usually add 8”/20cm to the drop to get the length of fabric needed. This gives 2”/5cm of turning at the top and a double thickness hem of 3”/7.5cm at the bottom.
Next, check your fabric for a pattern repeat. When curtain fabric has a pattern and you need more than one width of fabric, it is usual for all curtains or joined fabrics to start at the same place on the pattern in order to make them match. (For vertical stripes, plain fabrics or only one width of fabric this step is not needed). Take the fabric length and divide by the fabric repeat, then go up to the next whole pattern repeat
eg. Drop = 140cm
Add hem allowance of 20cm = 160cm
Divide by pattern repeat of 65cm = 2.46
Go up to the next whole pattern repeat = 3
Then multiply the whole number of pattern repeats by how much the pattern repeat is and you get the length of fabric needed for each width. In our example this is 3 x 65cm = 195cm. Note : if your fabric pattern is a half drop repeat then you may need to add more fabric here for matching widthways.
Finally, multiply the length of fabric for each width by the number of widths you need to get the total amount of fabric you need. In our example this would be 195cm x 3 = 585cm or 5.85m of fabric needed. Be sure to add in any extra fabric you need such as for tabs, tie-backs, cushions, piping or pelmets. You will usually need to buy the next whole metre of fabric (in this case 6) if shopping online, although we can cut to more exact lengths in the shop.
If you have been calculating in inches you can convert to metres at this stage by dividing the total number of inches by 39.
If you are shopping with us, we can calculate your fabric requirements for you. Either call in to the shop, or email us letting us know which of our fabrics you are interested in and your measurements taken as above (make sure you say whether the measurements are inches or centimetres – we’re happy with either). We’ll do the sums and let you know how much fabric you will need.