We eventually decided on 1/2" hardware cloth after some long hard thought about our situation. For us, hardware cloth makes the most sense because we are in a very urban neighborhood with lots of predators, including children (who last year proved they had no problem coming into our garden and trampling our plants to get a look at our dogs, I figure they just won't be able to resist the lure of chickens, so THIS year we've erected a fence on our raised bed garden, it's almost 5' high in total . . . no more kinds tromping through the garden, we hope! There's a 4' chain link fence between the garden and our coop as well, so the kids would actually have to unlatch our gate -- which is now electrified thanks to some substandard wiring in the garage and a new motion sensing light. . . not a bad thing, really . . . anyhow . . . ).
We also have at least one raccoon and two semi-feral cats who basically keep not only the mouse, shrew and vole population down but also the rabbit, squirrel and songbird populations from gaining. I watched one of the cats recently stalking a crow, so I know it would see our chickens as a handy snack. I haven't seen the raccoon around in about the last 18 months, but where you see one, more are around somewhere!
We also have red-tailed hawks in the vicinity as well as bald eagles within a couple miles. Yeah. Hardware cloth is a must! In fact, one of the reasons I picked the coop plans I did is because the top of the coop, even before you put the wood rafters and the "indestructable" Sun Tuf on, is covered in hardware cloth!
We've jokingly called our coop Coop Knox, but there's no way I'm gambling with my bird's safety. We're also putting padlocks on the human sized door and the egg door, instead of the typically recommended latches.
Maybe if we lived out in the country somewhere and I was assured of good neighbors with good kids, and could run a double electric fence to keep predators out (and have an electrified fence over the top of the chicken run also . . . ), I would feel safe using chicken wire. But in our current situation, using chicken wire is just asking for trauma.
You might be able to find a deal on hardware cloth on
Ebay, Freecycle, Craigslist or your local Habitat for Humanity REstore, or similar. You never know!
Whitewater