It is an unfortunate fact that the very nice bedcoverings out there are not meant to be laundered. I don’t have the money nor inclination to drop off a duvet every week at the dry cleaners because my dogs LOVE to get up on the bed and romp around… Even a duvet cover for a king size bed is too much fabric for the washer.
I made this cover, with pleats at the corners, from a king size sheet set I found at Walmart. The fabric is a bit scratchy for me and has polyester in it so not something I would choose to use for sheets but it worked great as a bed cover. PLUS it’s got a pattern, which you never see anymore! I used the flat sheet as the main part (no seams!) and cut up the fitted sheet to make the sides and end. The seams at the corners are hidden in the pleats. A big plus is that it is very long so can cover and fold over the back of your bed pillows and is almost impossible for the dogs to get to the bedding or pillows underneath. It is machine washable and, I guess because of the polyester, wrinkle free.
I made this second set for an aunt whose German Shephard sleeps at the foot of the bed. Once again I used a sheet set from Walmart (They still sell these.) Her bed is a queen so I used a queen set. I used the leftover fabric to make these cute ruffled pillows.