I'm not crazy about the way the back of my pieced knit afghan will look. So I've been thinking about backing it. I'm using a washable acrylic (I'm allergic to wool). Has anyone seen a backed knit afghan before? What type of fabric was used?
You know, I think I do remember seeing a backed afghan on the internet somewhere, but I can't remember where. I don't see why it wouldn't work. Since your afghan is made of acrylic, it shouldn't shrink much, if at all. So if you use a backing that might shrink, I think I would wash the material before sewing the backing to the afghan.
If I were to back a knitted blanket or afghan, I'd make sure the backing material was as stretchy as the knitted front. This way it won't cause bagging. I'd also stitch it here and there all over the afghan, rather than just the edges, like you would a quilt perhaps.