My current coop was not built to be a deterrent to critters. I assure you the next one I build will be Ft. Knox. Im going to overdo everything. Im going to put real plywood, not sheeting, on the sides, and the celing. Then put tin on top of that plywood. IM going to put angle type sheet metal on every seam. Ill have a closed run on top. Then on the sides, ill dig a trench 8-12 inches deep and sink the wire into it then pour concrete into it. Nothing will dig in, or chew through. Ill use hardwire cloth for the first 3 feet if not the entire pen. Im tired of squirrels, rats, possums, and coons. The next time I build im doing it right. Im also running power and electricity into it. Ill have a brood box setup ready for the inside of my 8x16 foot coop. Im then going to paint it so it never has to be replaced. It will be epic. Im so irritated at the critters messing with my girls, including the coon that killed 2 and maimed 2 more. The maimed ones healed, but had nasty wounds.