I use Hobbs 80/20 fusible batting and I wash my quilts when I finish FMQing them. I put it in the top load washer and do a brief wash and pin cycle. I then put my quilt in the dryer and get it out when still damp. I lay a sheet out on the carpet in the spare bedroom. If I want the quilt nice and flat, I lay my quilt on the sheet and pin the edges to the carpet and let it dry that way. I have minimal shrinkage( it looks almost the same as before washing)