Here is general advice on measuring your windows. Decide first whether you want your curtains to hang from a pole or a track. These should be positioned 15cm(6 inches) above the window and should extend some 15 to 20cm either side. Please take time to measure the window carefully. It is advisable to use a metal tape measure for accuracy.
You should fit the pole or track before taking measurements.
Measure the Pole for pencil pleat from the eye which is the small metal ring at the bottom of each curtain ring. This way you will be making sure that the curtain is not hiding the pole or rings.
Measure the tracks from the top.
Measuring length
Decide first whether you want your curtains to fall to the sill, or below the sill or to the floor. Then proceed to measure accordingly. Please take into consideration the following:
1. To fall to the sill the curtains must finish 1.25cm(half and inch) above the sill.
2. To fall below the sill the curtains must finish 15cm(6 inches) below
3. To fall to the floor the curtains must finish 1.5cm(half an inch) from the floor (some people feel that they can create an individual, romantic, or Bohemian look if they have the curtain a bit longer so that they actually trail on the carpet.
Measuring Width
1. Exclude the finials when measuring the width of the pole or track.
2. Do not measure the window unless it is a wall-to-wall window.
3. Allow for an additional measurement to allow for overlap which is normally 2.5cm(one inch). This is for the curtains to hang with an overlap in the middle when closed.