That depends on how wide you need your bias tape. Here is a basic calculation and you can adjust for your needs. Most yardage is around 40" wide of usable fabric, so with the seam on the vertical - you will get approximately 1 yard of bias tape for each cut. If you want 1" single bias tape, you will make strips that are 2" and you will need 4 strips or 8" of extra material. Double bias tape would be twice that length. .5" single bias tape would have 1" strips and you would need 4" material.