I'm new to chicken keeping and purchased a premade coop for my four pullets at Tractor Supply. It was cute and would look nice in my suburban back yard. The add said it accommodates 6-9 chickens but my 3 month olds are already super crowded. I'm pretty crafty and thought I could come up with a more comfortable. I purchased a dog run, (4x6x8 feet) and I'm planning on modifying an old dresser to be a nesting box/shelter. My question is, how much covered indoor space do four chickens need? I live in Central California so it doesn't get too crazy cold. I know they're supposed to sleep on roost bars but they're currently sleeping in the inclosed part of my store bought coop. Help!