I bought 108" wide fabric for king size quilt backing at JoAnn Fabrics. It's 100% cotton so preshrunk it in hot water wash & dryer. Well, its width went from 108" to 92" -- 16" shrinkage in width! Called the JoAnn store & clerk told me "It should've 'only' shrunk 8 inches"! If I'd been advised of that before I bought it, I'd have selected a poly/cotton blend instead. I'd bought an extra 3/4 yard, thank goodness, so ended up having to cut the excess length off & turn it crosswise grain and sew onto the sides to get enough width. Then I washed it again, in hot water, and dried it again to be sure it's done all the shrinking it's going to do, hopefully!
Do you think future washings in cold water should be safe??