I converted an 8X8 shed into a coop and added an 8 X 12 hoop run for my small flock ( a dozen or so birds at any given time ). Used 1/4" hardware cloth on all the windows, doors and the run, secured with drywall screws and washers. I did the hardware cloth skirt around the outside of the run and a skirt on the inside where the run butts up to the coop. I leave the door between the coop and the run open 24/7 so the flock can go in/out as they please. Haven't lost a chicken in the 3+ years I've had them (they free range on the weekends when I'm home). The run was expensive but will last many, many years and will protect my flock from the predators we have here in NH: bobcat, weasel, raccoon, coyote, fox etc. These birds are in my care and I feel obligated to protect them. Couldn't imagine one having it's head ripped off as a raccoon tried to pull it through chicken wire. And the other comments here about weasels are absolutely correct. We have two ferrets and they can very easily climb up the hardware cloth and they get into things in the house through the smallest spaces.