If you use 7 blocks of width and 8 of length, a quilt with 14" blocks will require 56 blocks. The most simple pattern would use 7 strips per block for a total of 392 14 1/2" strips. Of course, 3 14 1/2 inch strips per WOF strip is pretty optimistic. It would require that the WOF be almost 44", If you are lucky and can get 3 pieces per WOF strip you will need 392 pieces, which breaks down to 131 WOF strips or over 3 jelly rolls. If you can only get 2 pieces per WOF strip you will need 5 jelly rolls. I am assumming 40 strips per jelly roll.