The pre-cuts I normally use are fat quarters and fat eighths. I notch all fabric when washing; this helps control the fraying. The fat quarters I wash as with yardage; the fat eighths I put in a garment bag to wash, but then add to the dryer out of the bag with the rest of the load. I did once wash a jelly roll and a layer cake. The layer cake shrunk unevenly, so that the pieces were no longer square; the jellyroll (pinked edges) did not shrink considerably in width, so I was still able to use as 2 1/2" strips.