How to Make Box Cushions with a Zipper | OFS Maker's Mill
For the back boxing, you will need two pieces that are about 26" long x 3" wide.) If you cut your strips vertically (going from selvage to selvage, you'll need roughly another 1/2 yard of fabric. So this comes out to 1 1/4 yards per cushion. Personally, I would round this up to 1.5 yards per cushion to be safe. For 10 cushions, this means 15 yards.