We've attached wire over wire before and it's a pain and gaps form and although galvanized is not supposed to rust it still does. The wild birds are a nuisance but not the danger that coons and possums pose - so the heavy dog kennel wire we have on the Barn Coop will most certainly keep those night critters out for sure!
I agree! I live in rural Colorado lots of predators here. That's why I choose dog kennel panels and attached 1/2 inch hardware cloth running 2 ft up and 2 ft out. I also have 2 dogs that patrol the backyard from sun up till 10 or 11 PM. Though the wife and I have spotted predators close by none have yet dared to enter our fenced in backyard where the chicken coop is. I'm not sure if they sense the dogs or "Hey this guy has a rifle, he'll shoot us if we mess with his hens."