Mid-sleepers or cabin beds as they are sometimes called, tend to not be as high as traditional bunk beds, but they still allow you to free up valuable space beneath the bed.
If your child has a small room and no play space downstairs, raising the bed a few feet off the ground can really grow the area they have within which to play. And, invest in a bed that doubles up as a Wendy House and yours will be the house everyone wants to play at.
Of course that space could also be used for extra storage too. Fill it with a chest of drawers, a book case and a toy box.
Or you could even slip a pull out desk and chair under there.