I am planning a coop for around 15 chickens. I have a 10' x 20' run that I am going to attach some sort of hen house to. I know I have plenty of room in the run, but my question is in the hen house what is the base amount of space I can get by with? I know the general guideline people go by is 4' per chicken. What I'm interested in is people's own experiences. In your experience do they do ok with less space or do they actually need more? How much space per chicken do you have in your house?