I have made patchwork cotton shower curtains. I have never used batting of any kind. I have used washed muslin as lining. The last time I used an inexpensive cloth shower curtain liner for the backing. I always wash all my fabrics before sewing so shrinkage was not a problem. I also use an inexpensive vinyl liner in back. I live in a humid climate and these have washed and worn well. Hope this helps ...
