That makes sense, for heat loss. I never thought of that. Yeah my ladies like to lay all the eggs in a big pile then one will fight everyone out of the house and sit on the eggs for an hour then once the boiled eggs served she's over it, haha.I only have cots. The brood patch is just a summer feature I think, helps keep them cool in the heat too I assume. A couple of mine sit on the egg a for five minutes or so, sometimes tossing straw around or stealing eggs that are already laid. They always get up and leave afterwards. Definitely keeping them on soil is necessary for nesting, if I made a separate pen with a lot of hiding spots I could probably convince one of my hens to brood, this year I think she is just too young.
How old do you think they should be to brood? If I separate the girl who brooded this summer into a ground pen with a male do you think she'll brood? They're in cage on wire but they have a deep litter area (grass clippings from the lawn mover) in their 'house' that they lay eggs in, which is also where she brooded for 2 days (until I accidentally changed the bedding bc nobody told me she was brooding).