Many of my silkies just pick a corner in the shavings and defend it from all, even if they have a nest box. They sleep in dog houses or small coops, though.
I do have a small tote I cut a hole in the front of that they like. Left a lip a couple inches to keep the shavings in but it isn't too high for chicks if they fall out. I always put a ramp of shavings in the front for the first week.