I used a flannel backing on a queen size quilt and put 80/20 batting in it, too. Be sure to wash and dry the flannel 2 or 3 times because it shrinks terribly. I hope you bought extra - LOL. BTW that quilt is so heavy I can hardly fold it but it sure is warm. If I use a flannel backing again I won't put batting in it - we don't need all that here in TX.