About 6 weeks ago I ran outside to the godawful sound of a screaming/howling chicken and found a raccoon reaching through a hole in the chicken wire top of my run, trying to pull one of my chickens (now dead) through the hole. I yanked on the lower part of the chicken, keeping that part for myself, and the raccoon ran off with its head. That is what chicken wire can do for you to protect your chickens. Hardware cloth they cannot so easily break through. People will show you photos of racccoon cages sturdily built with tougher than hardware cloth sides which a coon has bent trying to escape. But coons will do far more damage desperately trying to get out, in my opinion, than trying to get IN. Hardware cloth or welded wire do well for the whole run. I used chicken wire only for the upper part that goes around tree branches and that ended up being the weak area.