Chicken wire Will. Not. Do. It. if you know already that you need to keep raccoons out.
You need to use heavy gauge 1/2" hardware cloth and you need it to cover any portion of your construction that isn't sturdy wood or other study building material -- those suckers can chew and scrape as well as climb. You need to secure your hardware cloth to your structural elements and your window openings with washers and screws -- if they get their agile little paws under something they'll work it off. You need to dig it in 12" - 18" down to prevent digging and tunneling into your enclosure OR you need to create an apron 12" out from your perimeter. I'm dug in AND I have 12" concrete pavers up to my enclosure. I'm not taking any chances in my urban LA neighborhood 'cause I've battled raccoons and I have great respect for their abilities.
After you do that you need to make a thorough examination and see if there are any gaps you've missed. Look high and look low -- raccoons look big and bulky but that's all squishy fat and they can squeeze through incredibly small openings.
Next you need to make sure your latches have back ups like carabiner clips that prevent the latches from being lifted and released You need to secure the door to your enclosure, the door to your coop (if it isn't fully enclosed within your perimeter, and the collection port on your nesting boxes (if they extend into the exterior). The good news is they can't simultaneously squeeze the spring on a carabiner and rotate it out of a latch. They're clever but not that clever, thank god.
If you do all that you'll be OK. And that's saying a LOT because you probably already know that raccoons are smart, agile, diligent and unrelenting when they've identified a potential food source. If you've secured it all you can also be confident that rodents aren't going to get into your coop. That's a major accomplishment too because keeping them out is a WHOLE lot easier than getting rid of them after they've gotten in.
