Smallest size I can make a pop chicken door?

[jaycee]

Hi I have a small question about coop design. My 8 X 12 coop with a gable roof is done except for the trim and a few other finishing touches. Just finished the roosts and my chickens have already been sleeping in there for almost 2 months. I have an assortment including barred rocks, production reds, and buff orpingtons. My question is... I would like to make a small pop open chicken door so they can go in and out without the big door standing open, and I would like to know the smallest dimensions that anyone has used successfully for these full size breeds. The reason this is important to me is that I need to use the chicken yard which is about 50 X 75 as a temporary pen to wean four 3 month old nubian does during the daytime. They will weigh about 40-50 lbs, the size of a medium dog, and they are very crafty about getting through small spaces in my experience. Well I dont want them to have access to chicken feed inside the coop, so the smaller I can make the opening the better... any help is appreciated.

Thanks!

 

[4 the Birds]

Our coop is within a very large fenced goat pen. The chickens free range in the goat pen via a small door in their run. Our Alpine/Nubian goats (full size) had no trouble shooting through the smallest of doors. It is incredible how nimble goats are and how they can fit through holes! I downsized the opening to 9" x 10" and they could still get in! Our solution was not the door size but to add short posts just outside the door and buried in the ground (about 12" away so that you can still close the swing door). This solved the problem. The goats cannot navigate a tight turn to get into the chicken door. I also connected a beefy size cross post from the vertical posts to the run to keep it stable. I can post a picture if needed.

 

[jaycee]

Thanks John I think I understand the concept and it sounds like a great idea... would love to see a pic of your design too if you get a chance and its not too much trouble... I should have known even a tiny door might not dissuade those goaties... I was trying to make a way for my dogs to get into the pasture and the goats to not get out... thats harder than it sounds because a goat can get through about anything a dog can... I thought I had a winner when I ran a 12 inch diameter culvert 2.5 feet long through a ditch under the fence and began training my dogs to crawl through. Out of 4 dogs I had 1 trained when those darn goats figured it right out!