I'm not sure what we're looking at here, other than nesting boxes.  Is that their roost above the boxes?  I would also recommend a lot more ventilation.  Fully feathered hens don't need to be enclosed in a box and kept warm.  It's more important to have clean fresh air - the ammonia from their droppings can make them very sick with respiratory problems.  Some ventilation up high above their roosting area will enable vapor/condensation/smells to rise up and out of coop; high enough so that if there is a breeze it's not drafty on the sleeping hens.