the oldest coop has a aluminum truck topper or cap on it for a roof... It has a crankout window on each side... unfortunately the front window on topper is stationary... I can walk into the coop so the unit is about 6 ft tall plus the heigth of truck cap or topper It is nice and bright inside the people door is approx 5 ft 9 or so. made from a palet wood and hdwe cloth then a storm window screwed to outside. now there is a strip of2 or 3 ines tall hdwe cloth above people door and topper frame and back window of topper... we have an outdoor woodburner... smoke goes everywhich way from it. it is approx 30 feet from back of house. coops are approx 100 feet from house just wish coop were further down property but cant change anything. permanent fencing and runs plus so much it hilly of property. was opening the windows some of topper coop. so cold now closed windows.... only 4 chickens in coop.... so yall think enough ventilation for the 4 ? Im leary of opening their crankout windows for fear of wood smoke..... If I did open window it would be on the left side.... I have watched the smoke and sometimes it goes in run esp during day can see it occ. Now they range 1/2 acre so they can avoid woodsmoke during day.... But dont know how much may be getting in at nite.... snow outside and cold so thoughts?