On existing fittings taking measurements from existing tracks and poles is quite straightforward. Measuring for tracks, measure the width of the track, allowing 7.5cm (3″) overlap in the middle. Measure from the top of the track and not the runners, as if you measure from the runners the curtains will not cover the track when pulled, to the floor, or if a short window to 12-15cm under the windowsill.
Measuring for Poles
Measure the width of the pole between the finials, allowing for a 7.5cm (3″) overlap (if the pole has a central bracket this allowance will need to be slightly larger), plus returns if you wish to return the ends of the curtain to the wall. Measure from the bottom of the ring to the floor, or 12-15cm below the sill.
Where to fit your Track or Pole
Fitting Curtain Tracks Generally tracks are fitted approximately 7.5cm (3″) above the reveal and will continue pass the side reveals by 15cm (6″), you can of course come pass the sides of the window as much as you wish if you have the space. Although when the curtains stack back at the sides you really want them to cover the sides of the window. Measure for your curtains and same as above. Fitting Curtain Poles Poles are fitted slightly higher above the reveal, as the curtains will hang under the pole, approximately 12.5 cm (5″) above the reveal, and will continue pass the side reveals by 15cm and then the finials. Measure for curtains the same as above.
How Much Fabric do I need?
To calculate the amount of fabric you need for curtains, take the width of the track and multiply by 2, 2.5 or 3 times for fullness, divide this number by the width of the fabric, this will give you the number of fabric drops for your curtains, divide this by 2 and you have the number of drops per curtain. To calculate the length of drops, take the finished length of the curtains and add 25cm (10″) for the hem and turnover at the top. If a patterned fabric you need to divide by the pattern repeat and the number of full pattern repeats will be your cut drop length. Multiply the cut drop length by the number of drops and this will give you the amount of fabric you need to make your curtains.