I washed mine once after spot cleaning caused spot shrinkage and wrinkling. So I figured I may as well wash them in hot water to get all the shrinkage out of the way. They did shrink alot, they are canvas (Gammill). Ironing the wrinkles out of them was a huge, huge job, not easy to get wrinkles out of heavy canvas. i thought I'd never get done ironing them. But now that they are clean, if I do get a spot, I can spot clean them and not worry.