have just been given six game chickens...was told that i could just let them free range and have been doing this for the last six weeks...they roost in the trees...but i am concerned for their safety...so i think i am going to build a pen under part of my barn shed. it has a wall on one side. my question is that should i just put up nesting boxes or go ahead and build a house for them too. i was told that if i extend wire around the perimeter of the pen out to three feet and one foot inside that this would be sufficient to keep varmits out. i live in south mississippi and am not sure if my chickens will be warm enough in the boxes which will be twelve inches square, etc. any advice would be greatly appreciated.