Last year when we started our chicken adventure, I said 12 was enough and all i'd ever need... HA! We had an existing double camper "car port" on our property and decided to work with that for our chicken area(it is 40 feet long by 20 feet wide). We fenced in the whole carport as a run, then added an 8ft x 8ft chicken coop on the inside. Now that we are adding an additional 16 chickens (total 28), we are wanting to add some more nest boxes, but we don't want to put them on the inside. We have a five box setup in the coop now, and looking back, we should have built it so they go enter from the inside, but the box be out. My question is this... is there a reason why one couldn't put the nest boxes on the outside of the coop?