Glossary
Hardware cloth
Welded wire mesh that keeps out predators. Chicken wire keeps chickens in but does not stop predators.
Hardware cloth is a welded wire mesh, usually made of galvanized steel, that is strong enough to stop digging, prying, and reaching predators from getting into a coop or run. It is often confused with chicken wire, which is a thinner, twisted mesh designed mainly to contain birds rather than keep anything determined out, and which a raccoon can reach through or a dog can tear with little effort.
Mesh size matters as much as material. A half-inch opening blocks most rodents and snakes, while the more common one-inch mesh is easier to work with but still allows small predators to reach through and grab a bird pressed against the fence at night. Hardware cloth is typically used on coop windows and vents, run walls, and the underside of elevated coops where a predator could otherwise dig straight up into the floor.
A common mistake is treating chicken wire as if it were predator-proof simply because it looks like a solid barrier, when in practice it mainly keeps chickens from wandering off. Pairing hardware cloth on the fence itself with a buried or outward-laid predator apron closes off the two most common ways predators actually get into a coop and run.