FABRIC QUANTITY
Very often cushions are piped in a contrast fabric. So we will look at the fabric required for the piping separately from the fabric required to cover the cushion.
PATTERNED FABRIC CONSIDERATIONS:
FABRIC TO COVER THE CUSHION:
We use a 2cm seam allowance when making a piped zipped cushion. The size of the fabric panel you cut depends on how soft or firm you want your cushion to be.
For a FIRM CUSHION
For a SOFT CUSHION
FABRIC TO MAKE THE PIPING:
To make the cushion we need a continuous length of piping at least 5cm longer than the perimeter of the cushion pad .
eg: A 51cm x 51cm cushion pad requires a length of piping 209cm long.
You will need a a strip of fabric 5cm wide and the length of the piping cord (it may need joins). To further complicate things best practice is to cut the fabric on the bias. That is where the fabric strips are cut across the grain of the fabric at an angle of 45 degrees to the fabric roll (to improve the bend of the piping on the corners).
SEE CINDY'S CUTTING PIPING VIDEO in STEP 3 , where she talks through cutiing on the bias or straight for your piping strips.
CONSIDERATIONS:
Cutting the strips at 45 deg to the grain is best practice as it allows the fabric to stretch when bending the piping around a tight corner. That said you can cut straight strips with the grain. It will work and uses less fabric.