I love to use flannel as quilt backings. I always pre wash them. I buy flannel sheets. LL Bean sheets are really nice, don't pill and they sell flat sheets separately, so you don't have to buy a whole set. You can usually find LL Bean coupons too. I work at Kohls and I will be watching for Kohls flannel sheet sets to go on clearance. Then the prices are really good! I usually grab king size because then I have enough to back any size quilt....and it's cheaper than buying fabric by the yard and you won't have to piece it! I didn't like the flannel at JoAnns....it pills!