Howdy all - I am almost done with my new coop (willpost pics soon!) but I think I cut their little entry door too small - the one they use to enter the enclosed area at night, they walk up a little ramp. I cut it about 12" but it looks too small. The chickens are only 6 weeks lod right now, but they shoud grow to normal adult size - medium to large breeds. How tall is an adult chicken & how tasll does thei doorway need to be? Do they mind stooping?