Calculate fabric amount for curtains

by on March 29, 2010

How To calculate Fabric Amounts For Curtains

The design of your chosen curtain heading and the hanging method you choose is the key to the amount of fabric you will need to buy to make your curtains.

By now you should know the type of curtain heading you want to achieve. And you’ve installed an appropriate track or pole system over your window.

So now you’re ready to measure up for the fabric quantity you need to purchase.

1) Measure the width of your curtain pole or track, exclude the width of finials if using a decorative pole. But do include the width of the return brackets on your curtain track or pole if you have them.

2) Multiply this width by 1.5 x, 2 x, 2.5 x or 3 times, depending upon the amount of fullness required for your heading (see below).

Goblet pleat/Triple pleat               : multiply your width by 2.25 x – 2.75 x

Slotted, cased, channelled            : multiply your width by 2 x

Pencil pleat                                  : multiply your width by 2 x – 2.5 x

Eyelett/Tabbed top                      : multiply your width by 2 x

Sheer curtains                             : multiply your width by 3 x

Divide this number by the width of your chosen fabric.
(Standard fabric is normally 137cm (54″) wide, but check when you buy).

Round up to the nearest whole number. This is the number of widths of fabric required.

Measure the finished length of the curtains you require. (see how to measure for curtains)

Add 20 cm for turnings, and this gives you your cutting length.

Multiply the number of widths by the cutting length. This is the amount of fabric you need to buy if the fabric is plain.

180cm  x 2.75 = 495cm

Divide 495cm  by the fabric width 137cm  = 3.6widths

Round this up to 4 widths.

Therefore your cutting length needs to be 170cm and you need 4 widths for your curtains. Therefore you need 4 x 170cm = 680 cm.

So you would need 6.8 metres of fabric, assuming you are using a plain fabric.

If you are buying a fabric with any kind of pattern, you will need to pattern match the fabric, so that when the curtains are drawn together, the pattern is the same on both curtains.

To allow enough fabric for pattern matching, add the following calculation:

Find out the pattern repeat for your chosen fabric.

Take the cutting length you have calculated and divide this by the pattern repeat. Round the number of pattern repeats up so that your cutting length increases.

Use this new, final cutting length and multiply by the number of widths. This is the amount of fabric you need to buy for fabric with a pattern repeat. ( If the pattern is distinctive and you would like to be able to choose where you make your first cut, add on an additional pattern repeat to the final amount of fabric.)

Follow this example using the same details as the example above.

You know that you need 4 widths of fabric, from the calculation above.

Your finished drop is 150cm + 20cm turnings = 170cm

Divide 170 cm by the pattern repeat of 48 cm = 3.54

Round this up to 4 x pattern repeats per drop giving you a cutting length of 192cm.

Your new fabric amount is 192cm x 4 widths = 7.68m.

You can then round this up to 8 metres if you like, so you can choose where to make your first cut on the pattern.

And you are ready to start.

Remember the golden rule – Measure twice – cut once!