A periodic care step in which a rug is turned over, or has half of it folded back at a time so the whole piece never has to be flipped, and its reverse side is vacuumed to loosen dust and dirt that has worked down through the pile; debris that has collected beneath the rug can then be swept up. It is recommended about every one to two months, alongside vacuuming the pile side across the rug's width every one to two weeks (about monthly in a little-used room), and it is optional rather than essential.